<figure><img src="image_144.png" /><figcaption>Figure 1: Technical drawing of the experimental setup used in the E805 experiment. On the right side, photographs of the two CATS beam trackers (upper part) and of the MUST2 charged-particle detection array (bottom part) are shown.</figcaption></figure>

<figure><img src="image_145.png" /><figcaption>Figure 2: ΔE-TOF identification matrix of the <sup>48</sup>Cr secondary beam (97% of the total) obtained after the F62 slits using the LISE Wien filter.</figcaption></figure>

<figure><img src="image_146.png" /><figcaption>Figure 3: Online results obtained for the <sup>48</sup>Cr(p,d)<sup>47</sup>Cr reaction, showing from left to right the kinematic lines associated with the detection of light particles in MUST2 and the identification of heavy recoiling ions in the ZDD, and in the bottom picture the gamma lines deexciting the states populated in <sup>47</sup>Cr.</figcaption></figure>

<figure><img src="image_147.png" /><figcaption>Figure 4: Excitation energy spectrum for <sup>46</sup>V. The ground state is well separated from the other excited states. The 1+ state (of interest in this experiment) is mixed with other contributions and will be disentangled by the coincidence with gamma-rays.</figcaption></figure>

<figure><img src="image_148.png" /><figcaption>Figure 5: Angular distribution for the two-nucleon transfer <sup>48</sup>Cr(p,<sup>3</sup>He) <sup>46</sup>V g.s. It is peaked at 0 degree as expected for a L=0 transfer.</figcaption></figure>
## 2. Search for tensor type interactions in nuclear beta decay

Experiment number: E815 20

Date: April 28 – May 1, 2023

### Spokesperson and co-authors

O. Naviliat-Cuncic<fnref n="1" />,<fnref n="2" />, X. Fléchard<fnref n="1" />, G. Craveiro<fnref n="3" />, D. Etasse<fnref n="1" />, T.E Haugen<fnref n="2" />, L. Hayen<fnref n="1" />, M. Kanafani<fnref n="1" />, S. Leblond<fnref n="3" />, F. Lebourgeois<fnref n="1" />, E. Liénard<fnref n="1" />, J. Lory<fnref n="1" />, F. Marie-Saillenfest<fnref n="4" />, X. Mougeot<fnref n="3" />, J. Perronnel<fnref n="1" />, J.C. Thomas<fnref n="4" />, Ch. Vandamme<fnref n="1" />, V. Watt-Morel<fnref n="4" />

### Abstract

The Fierz interference term is the most sensitive parameter in nuclear beta decay to probe the existence of exotic (scalar and tensor) interactions contributing to weak decays, involving left-handed neutrinos. The experiment aims at extracting the Fierz interference term from the precise measurement of the beta energy spectrum in the pure Gamow-Teller decay of $^6$He with a total uncertainty of 0.004. Such a level of sensitivity will provide the tightest constraint on the phenomenological tensor coupling from any low energy experiment. The possibility for improving this level of sensitivity by an additional factor of 4 is being considered as a second phase of the project. Precision measurements of the beta particle energy spectrum were performed using both, high energy (LISE - 2023) and low energy (LIRAT - 2021) $^6$He beams.

### Experiment report

$^6$He ions were produced in the fragmentation of a $^{13}$C beam at 60.2 MeV/u in a 2 mm thick Be target. The secondary beam was purified using a 1 mm thick Be wedge-shaped degrader and the LISE Wien filter set at 3000 kV/m. A collimator was used to further define the beam shape, which spot size and alignment was checked using a hodoscope consisting of four plastic scintillators.

The energy spectrum of beta particles was measured in a beam On/Off mode using a calorimetry technique. For each cycle, the beam was kept on during 3 seconds for implantation and switched off for 12 seconds to record data during the beta decay. The $^6$He nuclei, extracted in air at an energy of 52 MeV/u, were implanted about 9mm deep in the volume of a YAP scintillator. The beta particles emitted by the $^6$He ions do not escape the YAP detector, thus eliminating the main instrumental effect in beta spectroscopy, which is the scattering and backscattering of beta particles on materials. The implantation detector was surrounded (Fig. 1) by a high-purity Germanium detector to monitor possible secondary beam contamination and by another YAP detector to measure Bremsstrahlung radiations escaping the implantation detector.

YAP detectors of two different volumes were used during the measurement, and placed at short and large distance from the extraction window in order to study systematics effects. A total number of ~$10^8$ decay events were recorded with a FASTER acquisition system, split in four data sets. The analysis of the YAP spectrum during implantation (Fig. 2) shows only pileup events and no sign of beam contamination (above the $10^{-5}$ level). Figure 3 shows a typical spectrum obtained during the beam off period of the cycles. Background subtracted $^6$He energy spectra will be derived after baseline and gain corrections will be applied.

### Copyright

© LPC Caen, GANIL

<footnote n="1">¹Université de Caen Normandie, ENSICAEN, CNRS/IN2P3, LPC Caen, Caen, France</footnote>

<footnote n="2">²National Superconducting Cyclotron Laboratory, Dep. Phys. and Astronomy, Michigan State University, USA</footnote>

<footnote n="3">³CEA, LIST, Laboratoire National Henri Becquerel, Gif-sur-Yvette, France</footnote>

<footnote n="4">⁴GANIL, CEA/DRF-CNRS/IN2P3, Boulevard Henri Becquerel, Caen, France</footnote>
<figure><img src="image_149.png" /><figcaption>Figure 1: Experimental setup at the final focal point of the LISE spectrometer.</figcaption></figure>

<figure><img src="image_150.png" /><figcaption>Figure 2: Time integration of the signal delivered by the implantation detector during the beam-off phase (⁶He decay).</figcaption></figure>

<figure><img src="image_151.png" /><figcaption>Figure 3: Time integration of the signal delivered by the implantation detector during the beam-on phase (⁶He implantation).</figcaption></figure>
### 3. Search for two-proton radioactivity and beta-delayed multi-particle emission in <sup>39</sup>Ti

**Experiment number: E839 21**

**Date: March 9-16, 2023**

**Spokesperson and co-authors**

V. Guadilla<fnref n="1" />, F. de Oliviera<fnref n="2" />, Z. Janas<fnref n="1" />, L. Janiak<fnref n="3" />, O. Kamalou<fnref n="2" />, G. Kamiński<fnref n="4" />, A. Korgul<fnref n="1" />, A. Kubiela<fnref n="1" />, C. Mazzocchi<fnref n="1" />, K. Miernik<fnref n="1" />, M. Pfützner<fnref n="1" />, J. Piot<fnref n="2" />, M. Pomorski<fnref n="1" />, B. Rebeiro<fnref n="2" />, A. Skruch<fnref n="1" />, O. Sorlin<fnref n="2" />, C. Stodel<fnref n="2" />, M. H. Stodel<fnref n="2" />, J. C. Thomas<fnref n="2" />

**Abstract**

The experiment aimed at measuring the decay of <sup>39</sup>Ti, a very neutron-deficient nucleus laying beyond the predicted di-proton dripline. This nucleus has been highlighted as an excellent candidate to undergo the very exotic two proton radioactivity. An Optical Time Projection Chamber (see Fig. 1.), was used to look for such two proton radioactivity emission at the focal point of the LISE spectrometer. Several beta-delayed multi-particle emission branches are energetically possible, but only beta-delayed two protons are known to be emitted from the isobaric analog state of the daughter nucleus, the proton unbound <sup>39</sup>Sc. The experiment should allow a clear determination of the energies and branching ratios of these beta-delayed two protons for the first time, as well as to identify unknown beta-delayed multi-particle channels. The clear determination of the energy of the beta-delayed two protons is expected to clarify the mass excess value of <sup>39</sup>Ti.

**Experiment report**

<sup>39</sup>Ti was produced in the fragmentation of a ~100 pnA <sup>58</sup>Ni beam at 74.5 MeV/u in a 100 µm thick <sup>nat</sup>Ni target. The secondary beam was purified using a 220 µm thick Be wedge shaped degrader and the LISE Wien filter set at 1500 kV/m. Radioactive ions were slowed down and identified by ΔE and ToF measurements using active silicon detectors located before the OPTC entrance window and two DELICAT fast gas detectors located at the focal planes of the spectrometer. The implantation range distribution of <sup>39</sup>Ti was fine-tuned using a rotating, remotely controlled passive Aluminium slower. A double conditioning was set online on the ΔE and ToF measurements with MSCA modules in order to reduce the triggering rate of the optical system of the OPTC to a few Hz. The "active gate" was applied on <sup>39</sup>Ti ions and on the main contaminants (N=17 isotones), observed at similar ΔE and ToF values. Figure 2 shows a representative ΔE-ToF identification matrix after the double gate conditioning.
In the first part of the experiment, a low-density gas mixture was used to favour the observation of the direct two protons decay of <sup>39</sup>Ti ions. In the second part of the experiment, a higher-density gas mixture was used to implant <sup>39</sup>Ti ions in the middle of the OPTC chamber in order to observe its beta-delayed charge particle emission. Both gas mixtures were at 1 Atm. The measured <sup>39</sup>Ti production yield of ~0.1 particle/h/pnA was more than 10 times lower than the LISE++ expectations. Data are under analysis but no clear evidence of direct two proton radioactivity was found in the first part of the experiment, thus constraining the possible branch to less than 0.5%. For the higher-density gas mixture, events with fully stopped beta-delayed two protons are being analysed in order to determine the mass of <sup>39</sup>Ti, an important input value for two-proton radioactivity models. In addition, hints of previously unknown beta-delayed alpha (see Fig. 3) and alpha-proton emission are under study.

**Copyright**

© University of Warsaw, GANIL

<footnote n="1">¹Faculty of Physics, University of Warsaw, 02-093 Warsaw, Poland</footnote>

<footnote n="2">²GANIL, CEA/DRF-CNRS/IN2P3, Boulevard Henri Becquerel, Caen, France</footnote>

<footnote n="3">³National Centre for Nuclear Research, 05-400 Otwock, Świerk, Poland</footnote>

<footnote n="4">⁴Heavy Ion Laboratory, University of Warsaw, 02-093 Warsaw, Poland</footnote>
<figure><img src="image_152.png" /><figcaption>Figure 176: OTPC setup at the end of the LISE beam line.</figcaption></figure>

<figure><img src="image_153.png" /><figcaption>Figure 3: Observation of a possible beta-delayed alpha decay event.</figcaption></figure>

<figure><img src="image_154.png" /><figcaption>Figure 2: ΔE-TOF selection of events triggering the OPTC DAQ.</figcaption></figure>
# 4. Study of <sup>68</sup>Ni by neutron adding and removing reactions

Experiment number: E843 21

Date: May 23 – June 3, 2023

## Spokesperson and co-authors

S. Koyama<sup>1,2</sup>, O. Sorlin<sup>1</sup>, D. Mengoni<sup>3,4</sup>, M. Assié<sup>5</sup>, O. Aktas<sup>1</sup>, M. Balogh<sup>6</sup>, D. Beaumel<sup>5</sup>, Y. Blumenfeld<sup>5</sup>, S. Bottoni<sup>7,8</sup>, D. Brugnara<sup>6</sup>, E. Clément<sup>1</sup>, G. De Angelis<sup>6</sup>, G. de France<sup>1</sup>, F. De Oliveira<sup>1</sup>, Q. Delignac<sup>9</sup>, N. de Séréville<sup>5</sup>, L. Dienis<sup>1</sup>, C.Aa. Diget<sup>10</sup>, B. Fernández-Domínguez<sup>11</sup>, F. Galtarossa<sup>3</sup>, A. Goasduff<sup>6</sup>, A. Gottardo<sup>6</sup>, J. Ha<sup>3,4</sup>, F. Hammache<sup>5</sup>, D.S. Harrouz<sup>5</sup>, O. Kamalou<sup>1</sup>, A. Lemasson<sup>1</sup>, A. Laird<sup>10</sup>, S.M. Lenzi<sup>3,4</sup>, S. Leoni<sup>7,8</sup>, M. Moukaddam<sup>12</sup>, D. Napoli<sup>6</sup>, M. Niikura<sup>2,13</sup>, J. Pellumaj<sup>6,14</sup>, R.M. Pérez Vidal<sup>6</sup>, J. Piot<sup>1</sup>, J.-C. Thomas<sup>1</sup>

## Abstract

The shell structure of <sup>68</sup>Ni was investigated via neutron adding (d,p) and removal (p,d) reactions during the LISE2023 experimental campaign using the CATS+MUST2+EXOGAM+ZDD setup (see E805 report). The measurement of the $d_{5/2}$ single particle state(s) in <sup>69</sup>Ni via (d,p) reactions with a slow-downed beam at 18 MeV/u will allow confirming its excitation energy and spin-parity, and to infer the size of the N=50 gap at <sup>68</sup>Ni. The complimentary measurement of neutron removing (p,d) and (d,t) reactions was also performed to investigate the neutron occupancies of <sup>68</sup>Ni. By combining the vacancy and occupancy of each neutron orbital in <sup>68</sup>Ni from the transfer reactions, the neutron Fermi surface at N=40 will be studied. These reactions should also enable to access the spin-orbit splitting of 2p 1f, and 1g orbitals in <sup>68</sup>Ni.

## Experiment report

<sup>68</sup>Ni was produced at ~38 and 18 MeV/u in the fragmentation of a ~40 pNA <sup>70</sup>Zn stable beam at 62.5 MeV/u in a 560 µm thick Be target. The secondary beam setting was the same at the two energies up to D4 where the beam energy was 38 MeV/u after a 570 µm thick Be wedge. For the 18 MeV/u setting, an additional 530 µm thick Be slower was set at an angle of 25° after the F43 slits, and a transmission of about 60% was measured up to the D6 room. <sup>68</sup>Ni beams of up to 1.6 10<sup>5</sup> pps were used at the two energies to induce transfer reactions on CH<sub>2</sub> and CD<sub>2</sub> targets of 5 and 0.5 mg/cm<sup>2</sup>, respectively.

For the <sup>68</sup>Ni(p,d) reaction, clear kinematics curves for the low-lying states in <sup>67</sup>Ni were observed online. The associated reconstructed excitation energy is shown in Fig.1 (a), compared with the data obtained with a 4 mg/cm<sup>2</sup> carbon target. Known gamma-rays at 694 and 1710 keV in the deexcitation of <sup>67</sup>Ni were observed in coincidence with EXOGAM (Fig.1 (b)), which absolute gamma-detection efficiency was of about 5% à 1.4 MeV. Fig. 2 shows a preliminary excitation energy spectrum obtained for <sup>69</sup>Ni in coincidence with the detection of protons in the MUST2 array.

## Copyright

© GANIL

<footnote n="1"><sup>1</sup>GANIL, CEA/DRF-CNRS/IN2P3, Boulevard Henri Becquerel, Caen, France</footnote>

<footnote n="2"><sup>2</sup>RIKEN Nishina Center, Wako, Japan</footnote>

<footnote n="3"><sup>3</sup>INFN Sezione di Padova, Padova, Italy</footnote>

<footnote n="4"><sup>4</sup>Dipartimento di Fisica e Astronomia, Università di Padova, Padova, Italy</footnote>

<footnote n="5"><sup>5</sup>Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France</footnote>

<footnote n="6"><sup>6</sup>INFN, Laboratori Nazionali di Legnaro (LNL), Legnaro, Italy</footnote>

<footnote n="7"><sup>7</sup>Dipartimento di Fisica, Università degli Studi di Milano, Milano, Italy</footnote>

<footnote n="8"><sup>8</sup>INFN Sezione di Milano, Milano, Italy</footnote>

<footnote n="9"><sup>9</sup>University of Bordeaux, CNRS, LP2I Bordeaux, UMR 5797, Gradignan, France</footnote>

<footnote n="10"><sup>10</sup>Department of Physics, University of York, York YO10 5DD, United Kingdom</footnote>

<footnote n="11"><sup>11</sup>IGFAE and Dpt. de Física de Partículas, University of Santiago de Compostela, Santiago de Compostela, Spain</footnote>

<footnote n="12"><sup>12</sup>Institut Pluridisciplinaire Hubert Curien, 67037 Strasbourg, France</footnote>

<footnote n="13"><sup>13</sup>Department of Physics, Faculty of Science, The University of Tokyo, Tokyo, Japan</footnote>

<footnote n="14"><sup>14</sup>Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Ferrara, Ferrara, Italy</footnote>
<figure><img src="image_155.png" /><figcaption>Figure 1: Excitation energy spectrum obtained in the <sup>68</sup>Ni(p,d) reaction (a), and coincident Doppler-corrected EXOGAM spectrum (b).</figcaption></figure>

<figure><img src="image_156.png" /><figcaption>Figure 2: <sup>69</sup>Ni* excitation energy spectrum obtained in the <sup>68</sup>Ni(d,p) reaction at 18 MeV/u.</figcaption></figure>
IV. D1-HE

<figure><img src="image_157.png" /></figure>
# 1. The immune system in Space - T-cell dysfunction mechanisms

Experiment number: P1211 and CORA

Date: July 10, 2023

## Spokesperson and co-authors

Silvana Miranda¹,², Randy Vermeesen¹, Ann Jansen¹, Emil Renhberg¹, ², Emre Etlioglu¹, Sarah Baatout¹,², Kevin Tabury¹,³, and Bjorn Baselet ¹,*

¹Radiobiology Unit, Nuclear Medical Applications Institute, Belgian Nuclear Research Centre SCK CEN, 2400 Mol, Belgium

²Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium

³Department of Biomedical Engineering, College of Engineering and Computing, University of South Carolina, Columbia, SC, 29208, USA.

## Abstract

The exposure to space stress factors such as cosmic radiation, altered gravity, and psychological stress leads to a disruption in various bodily systems. Dysfunction of the human immune system is caused by an alteration of the distribution of the cellular components and altered cytokine profiles, as well as cytoskeleton alterations and gene expression dysregulation. We irradiated CD4+ T-cells with iron ions, in combination with simulated altered gravity – microgravity, Mars gravity and Moon gravity – and stress hormone exposure. The effects of this exposure and possible causes were investigated with a transcriptomic, proteomic, flow cytometric and cytokine profiling approach. Our conclusion have the potential to enable the development and implementation of space-induced immune dysfunction countermeasures, with translational prospects for immune dysfunction pathologies which occur on earth.

## Experiment report

CD4+ T cells were obtained from healthy individuals and subjected to Fe ion particle radiation (within European Space Agency Continuously Open Research Announcement for Investigating Biological and Physical Effects of space Radiation ESA CORA IBPER) GANIL, Photon irradiation, simulated microgravity, and hydrocortisone, either individually or in different combinations. Cytokine levels for Th1 and Th2 cells were determined using multiplex Luminex assays, and RNA sequencing was used to investigate gene expression patterns and identify essential genes and pathways impacted by these stressors.

Simulated microgravity exposure resulted in a Th1 to Th2 shift, evidenced on the level of cytokine secretion as well as altered gene expression. RNA sequencing analysis showed that several gene pathways were altered, particularly in response to Fe ions irradiation and simulated microgravity exposures. Individually, each space stressor caused differential gene expression, while the combination of stressors revealed complex interactions.

The research findings underscore the substantial influence of the space exposome on immune function, particularly in the regulation of T cell responses. Future work should focus expanding the limited knowledge in this field. Comprehending these modifications will be essential for devising effective strategies to safeguard the health of astronauts during extended space missions.

Results from this experiment was submitted as an original research manuscript to Frontiers in Immunology (04/06/2024)

## Funding

Silvana Miranda is the recipient of an SCK CEN/UGent PhD grant. This work is supported by the ESA/BELSPO/Prodex IMPULSE-2 contract PEA4000140806. This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement n°654002. Irradiations at GANIL were financed through the P1211-H IPAC and CORA Project.

<footnote>* Spokesperson</footnote>
## 2. Modulation of a tissue specific radiation-induced inflammatory response by high LET radiation

Experiment number: P1341-H

Date: July, 11 2023

### Spokesperson and co-authors

I. Testard, S. Candéias, C. Rouichi, E. Chartier, A. Gattoni (CEA Grenoble, DRF / IRIG / DIESE / CBM)

### Abstract

The physical properties of ionizing radiation (dose, dose rate, linear energy transfer) are important factors controlling the biological response of cells and tissues. In addition to DNA damage response (DDR) driven by the activation of the ATM kinase (p53 pathway), an inflammatory response is also induced by radiation. These NFκ-B-dependent immune signalling pathways can promote cell survival. Hence, the concurrent activation of p53 and NFκ-B in irradiated cells plays a key role in the determination of cell fate by regulating the balance between cell death or survival.

Since these responses can depend on radiation quality in model cancer cell lines, our proposal aimed at comparing the effects of high LET radiation and X-rays on the radiation-dose dependence, kinetics and tissue specificity of radio-induced inflammatory response in primary human endothelial cells and fibroblasts. Our recent unpublished results show that high dose X-rays exposure induces an early and transient NFκ-B-dependent inflammatory response in endothelial cells, with a kinetics and a radiation-dose dependence distinct than that of p53 activation after DDR initiation.

The preliminary results of one ¹²C beam time experiment in July 2023 show that a similar inflammatory response, but at higher levels, is initiated in endothelial cells. In contrast, the modulation of the DDR pathway (DDB2 and p21 expression) is comparable in both low- and high-LET irradiations. In the next analysis steps, we plan to measure pro and inflammatory cytokines excreted in the irradiated cells medium taken up to 24 hours after exposure.

### Experiment report

In July 2023, a first ¹²C beam time (1 UT) was dedicated to our project. We exposed in D1 IRABAT normal human fibroblasts (HFPM) and endothelial cells (HUVEC) to native and/or degraded beam (95 and 26 MeV/u for HUVEC) to 4 different doses: 0, 2, 5 and 10 Gy. The corresponding LETs were 28 and 73 keV/µm, respectively. Due to beam concerns, we were able to irradiate our HFPM cultures only with 12C at one energy (26 MeV/u). Both cell types were irradiated in 25 cm² culture flasks. The cells and their conditioned culture media were harvested 6 h, 12 h and 24 h after irradiation. All doses and time points were realized in triplicates.

The cells were lysed for extraction of proteins and RNA to analyze the modulation of the expression of p53-dependent genes, involved in the DNA damage response (DDR) after ATM activation, and NF-κB-dependent genes coding for inflammatory factors in the different exposure scenarios. The conditioned culture media harvested from control and irradiated cells were frozen (-20°C) and will be used later to compare the level of secreted cytokines (soluble inflammatory mediators) and their effects on non-irradiated bystander cells.

In parallel, we irradiated our two cell models (26 MeV/u only) in thin 96 wells plates (for microscopy) at the same doses and time points, in duplicate wells. They were used for in situ immunofluorescence analysis of p53 phosphorylation and NF-κB nuclear translocation on the one hand, and RNA detection by ViewRNA® staining of p21 and MCP-1, two genes controlled by activated p53 and activated NF-κB, respectively, on the other hand. In these analysis, p53 phosphorylation and p21 expression, signed the activation of the DDR pathway, whereas NFκ-B translocation and MCP-1 expression attest activation of inflammatory signaling pathways.

We performed the same analysis on the same cell cultures exposed to equivalent doses of X-rays in order to compare radio-induced responses at high and low LET at the cell level.

We compared the modulation of a set of genes induced during the DDR and inflammatory responses by RNA analysis (RT q-PCR) in HUVEC cells exposed at 26 MeV/u and X-rays. The results are showed in the figure below for MCP-1, as a typical NF-κB target gene, and DDB2 and p21, as typical p53 target genes.
For both types of radiation, significant inductions were only observed at the higher 10 Gy dose. For low-LET X-rays, a peak in the expression of genes coding for inflammatory factors, such as the MCP-1 gene shown in A, is reached 3 to 6 hours after the irradiation at 10 Gy and the level returns to baseline 24 h after exposure (Figure below). The exposure to carbon ions results in a stronger induction of MCP1-expression measured 6 and 12 hours after exposure and, again, the expression returns to baseline after 24h. The same trend is observed for the lower doses (2 and 5 Gy) but no statistical significance is reached.

We next quantified the expression of genes involved in the DDR response. While we observed no significant difference in DDB2 induction with radiation quality, the expression of p21, coding for a protein involved in cell cycle regulation is induced with a more transient pattern in response to ¹²C ions than to X-rays.

For the in situ approach, the analysis of the images acquired on a CX-7® High Content Analyzer shows no clear modulation of the inflammatory responses as assessed by the nuclear translocation of the NFκ-B protein, whatever the radiation type. In the same samples, the DDR activation, assessed by p53 phosphorylation, is greater and persists over time in HUVEC cells exposed at all doses of high LET compared to X-rays radiations, indicating that there is less repair of DNA lesions in response to C-ions. We measured similar initial levels and disappearance kinetics of p53 phosphorylation in HFPM irradiated in the same conditions. The assessment of in situ mRNA expressions (p21 for DDR and MCP-1 for inflammation) is still ongoing. We acquired 150-300 cells per duplicate wells on the CX7® but image analysis needs further developments to allow accurate quantification and conclusions.

Inflammatory response is induced at a higher level and with a longer time course in endothelial cells exposed at high-LET carbon ions (26 MeV/u, 73 keV/µm). The analysis of the pro- and anti-inflammatory cytokines in the cell culture medium taken 6 to 24 hours after exposure, would bring more information of downstream effectors of this response. At present, we have not initiated this part of the study.

The mRNA analysis (RT q-PCR) is currently ongoing for HFPM irradiated with ¹²C at 26 MeV/u, and also for HUVEC at 95 MeV/u.

These first results show differences in the radioinduced responses initiated after the exposure of our cell models to different radiation type. A transient and strong inflammation activation is induced early after high LET exposure, whereas the DDR is activated later but lasts longer after X-rays. Thus, kinetics and radiation dose dependence confirm the measurements done after proton irradiation (unpublished results). However, the in situ approach applied here in addition to PCR analysis, does not totally confirm these trends. These experiments need to be repeated and comparisons established for the different LETs and cell types for significant conclusions.

As a result, an inflammatory state can be induced in normal healthy cells irradiated by accident or because of their vicinity of a treated tumor zone. The resulting pro- or anti-inflammatory processes can contribute to the orientation of the fate of these cells to a conservative or deleterious outcome. To better understand the involvement and interaction of both DNA damage and inflammatory responses, in our proposal, we want to use specific inhibitors of each pathways. To this aim, a second beam time in April 2024 allowed us to repeat the experiment at the higher LET (73 keV/µm) with the use in our cell cultures of Ku 55933 a specific inhibitor the DDR via inactivation of the ATM kinase. In parallel, comparative experiments were performed with our X-rays generator for irradiation at low-LET of our cell culture models treated with Ku 55933 or with Bay 11-7082 for inhibition of the inflammatory pathway via NFκ-B inhibitor.
Legend

<figure><img src="image_158.png" /></figure>

Modulation of stress and inflammatory signaling pathways in irradiated human umbilical vein endothelial cells (HUVEC). The expression of inflammatory (A) and DDR (B,C) genes was analyzed by RT-qPCR 6 to 24 hours after X-rays or carbon ions (26 MeV/u) 10 Gy irradiation. For each gene, the level of expression in control and exposed cells, and between irradiation modalities, were compared by an ANOVA test (n=3). When a value of p<0.05 indicated significant differences in irradiated cells (vs Control: ‡ : p-value < 0,05, ‡‡ : p-value < 0,01, ‡‡‡ : p-value < 0,001), pairwise comparisons were performed with a Tukey's test( * : p-value < 0.05, ** : p-value < 0.01, *** : p-value < 0.001). Above MCP-1 and p21 graphs, a view of the in situ mRNA staining (green spots for MCP-1, red spots for p21, nucleus in blue).

The phosphorylation of p53 (green foci staining) and nuclear translocation of NFk-B (red staining) was measured in HUVECs nucleus (blue staining) after in situ immunofluorescence detection (D). HUVECs were irradiated with 12C (26 MeV/u) at 0, 2, 5 and 10 Gy and fixed for analysis 6, 12 and 24h after the exposure (no data for 5 Gy, 12h). Histograms represent the mean number of phospho-p53 foci per nucleus, normalized to control non-irradiated cells, n=200-600. An ANOVA test showed that the data were not normally distributed then by a Kruskal-Wallis test, was applied for pairwise comparisons. All data are significantly different (**** : p-value < 0.0001).
V. D1-SME

<figure><img src="image_159.png" /></figure>
# 1. Radiolysis of polymers: LET and temperature effects

Experiment number: P1343-M

Date: June 09-10, 2023

## Spokesperson and co-authors (affiliation)

Stéphane Esnouf (CEA DES/ISAS/DRMP/SPC/LC2R)

Muriel Ferry (CEA DES/ISAS/DRMP/SPC/LC2R)

Solène Legand (CEA DES/ISAS/DRMP/SPC/LC2R)

Yvette Ngono (CEA DRF/IRAMIS/CIMAP)

Vincent Pacary (CEA DRF/IRAMIS/CIMAP)

## Abstract

The present proposal is a contribution to the understanding of the influence of temperature and Linear Energy Transfer (LET) on mechanisms of hydrogen release from polymers under irradiation.

Different kind of polymers (polyethylene, polyurethane, polyvinyl chloride, cellulose and polystyrene) were ion (9.04 MeV/u $^{22}$Ne) irradiated under various temperatures, from room temperature to 150°C, under inert or oxidative conditions. Gas release was measured in-situ using micro-gas chromatography. The results of this study provide data essential to elaborate of a relevant model predicting the gas release in nuclear waste for safety purpose.

## Experiment report (Between 1000 and 1500 words)

Polymers are components of nuclear waste in intermediate level waste packages. In these packages, these materials are in contact with actinides and degradation upon alpha irradiation induces inflammable and corrosive gas release. The accumulation of these gases can affect the integrity of the waste container. For safety purpose, it is thus necessary to predict the quantity of gases released by the different organic materials.

For the most common polymers, the influence of dose rate, dose, atmosphere and LET (Linear Energy Transfer) has been addressed. However, few studies have focused on the effect of temperature. This parameter is essentially relevant to transportation. The temperature inside nuclear waste packaging is supposed to be above room temperature (generally close to 50°C) and can increase up to 150°C during a short time in case of accidental conditions.

This work is dedicated to the influence of temperature on the radiolysis of polymers at high LET irradiation. The polymers of interest for this study are: polyethylene, aromatic polyester-urethane, polyvinyl chloride, cellulose and polystyrene. The impact of atmosphere (inert or oxidizing) was also evaluated.

The polymer samples were irradiated in a small chamber (CHIMERE2) designed by the CIMAP and the LC2R. A remotely controlled valve system enable gas sampling after or during irradiation and flushing the chamber. Gases were collected and analysed by µ-GC gas chromatography.

In addition to isothermal experiments, dynamical measurements were also performed. For this type of acquisition, the sample is heated at a rate of 2°C per minute from room temperature to 150°C and periodically the atmosphere is analysed. An increase of gas concentration is thus recorded as a function of the time or dose. After correction for successive sampling, the data are plotted as a function of the dose. If temperature accelerates gas release, the dose-response curve takes the form of a supralinear curve and an energy activation can be determined.

Our results show that temperature effect for ion irradiation is reduced compared to gamma irradiation (Furtak-Wrona K, Cornaton M, Durand D, Dauvois V, Roujou JL, Esnouf S, Ferry M, Temperature and LET effects on radiation-induced modifications in non-perfect polyethylenes, Polymer Degradation and Stability 162 (2019) 66-75). For example, hydrogen release upon ion irradiation of polyethylene is almost independent of temperature (energy activation equals to 0 kJ/mol) (see Figure below).
<figure><img src="image_160.png" /></figure>

Legend

Evolution of hydrogen concentration and temperature as a function of the ion irradiation dose.
## 2. Ion radiation chemistry in poly allyl diglycol carbonate: assessing the influence of radical migration in the defect creation mechanisms

**Experiment number: P1354**

**Date: June 4-9, 2023**

### Spokesperson and co-authors

Spokesperson:

Tamon KUSUMOTO (National Institutes for Quantum Science and Technology (QST), Japan)

Deputy Spokesperson: Remi BARILLON (IPHC)

Co-authors:

Yvette NGONO-RAVACHE (CIMAP-GANIL)

Satoshi Kodaira (QST)

Quentin RAFFY (IPHC)

Tomoya YAMAUCHI (Kobe University)

Masato KANASAKI (Kobe University)

Shunto SADAMITSU, (Kobe University)

Daisuke KOHINATA (Kobe University)

### Abstract

The aim of our study is to unveil chemical reactions of poly allyl diglycol carbonate (PADC) irradiated with heavy ions. To do so, PADC samples are exposed to 10 MeV/u Ne ions at 16 K under vacuum up to $2.0 \times 10^{12}$ ions/cm$^2$, with a fluence increment of $2.0 \times 10^{11}$ ions/cm$^2$, for minimizing the influence of the radical mobility. Then, PADC samples are annealed up to room temperature (RT) with an increment of 30 K. We have acquired IR spectra at each fluence and temperature step. In 2023, we focus on the absorbance around 3500 cm$^{-1}$, which is assigned to OH groups that form by radio-oxidation after the irradiation. Any changes in the absorbance are not seen during the irradiation. In comparison, the absorbance starts increasing above 200 K. This finding implies that the radical mobility plays important roles to decorate newly created ending groups after the irradiation.

### Experiment report

#### Introduction

Poly allyl diglycol carbonate (PADC) is a well-known Polymeric Nuclear Track Detector (PNTD). This material has been used in various branches, e.g., space radiation dosimetry, laser driven ion acceleration experiments and dosimetry for the targeted radiation cancer therapy. The application field is spreading out, but there are unsolved issues concerning the creation mechanism of latent tracks formed in PADC. The chemical structure of PADC is modified under ionizing radiations through the fragmentation of typical functional groups in PADC (ether, carbonate ester and CH groups). Damages to these moieties lead to release CO$_2$ molecules and alkene molecules and to form OH groups. This phenomenon was seen in the previous study, but their formation mechanisms were largely unknown. In the present study, we investigate defects creation of PADC under vacuum to get rid of the oxidation process and to focus solely on effects of swift heavy ions that is the creation of latent tracks. The aim of the present work is to elucidate roles of molecular and radical mobility in the creation of these defects under ion irradiations.

#### A brief history of our project

Thanks to a strong international collaboration between Japan and France, our team has conducted a series of FT-IR spectrometric studies to investigate structure and generation mechanism of latent tracks in PADC irradiated with protons and heavy ions. Especially, the influence of radical-mobility and radical migration should be clarified to unveil the creation mechanism of latent tracks in PADC. In 2018, we performed 11 MeV/u C ion irradiations at 11, 100, 200 K and RT. The radiation chemical yield (G value) of carbonate ester lost in PADC at 11 K is lower than that of RT. The G values of 100 K and 200 K are in between. The G value of CO$_2$ molecules generated is smaller than that of carbonate ester lost. It is known that CO$_2$ molecules are formed by the decomposition of the
carbonate ester bond. This smaller G value of CO2 molecules generated could be related to radical mobilities in PADC. Furthermore, no creation of OH groups is observed at the low temperatures. This finding would suggest that oxygen and radical mobility are necessary to form OH groups as new ending groups. We summarized results obtained in 2018 as a paper in Polymer Degradation Stability (Kusumoto et al., Polym. Degrad. Stab. 164 (2019) 102-108).

In 2019, we had beam time, but new data were not acquired due to the limitation of the beam time because of hit of the heat wave. From 2020 to 2022, we faced COVID diffusion, thereby it was not possible to travel GANIL from Japan for the beam time. Thus, we have no new experimental data during this period. We had difficult time for these 4 years, despite all that, our project re-started from 2023.

## Experiments of 2023 beam time

We prepared PADC films with 15 µm thick by chemical etching with KOH solution. This PADC film was made from BARYOTRAK, which is obtained from a monomer with a purity higher than 99%. The prepared film was too thick to quantitatively evaluate damages to carbonate ester, which has the strongest IR absorption in PADC, but was appropriate to have a look at the evolution of OH groups around 3500 cm⁻¹.

PADC samples were irradiated with 10 MeV/u Ne ions under vacuum at 16 K in the SME beamline. The fluence was up to 2.0 × 10¹² ions/cm². IR spectra were acquired using CASIMIR set-up, which equipped an in-situ FT-IR spectrometer, at each fluence increment of 2.0 × 10¹¹ ions/cm². After the irradiation, PADC samples were annealed up to RT with an increment of 30 K. We reduced temperature from each annealed temperatures to 16 K to minimize the influence of changes in the molar extinction coefficient with temperature. In the present study, we focused on the ether and CH groups lost and creation of OH groups.

## Results of 2023 beam time

### Damages to ether and CH groups and formation of OH groups during irradiation

The absorbance assigned to ether decreased linearly up to 7.0 × 10¹² ions/cm². Then, the linearity was broken. This trend would suggest the track overlapping in a high-fluence region. In comparison to this, the absorbance assigned to CH groups decreased linearly in the examined fluence region and the trend is gentle compared to the ether. Thus, the ether is more radiation-sensitive moiety than CH groups. Seeing the absorbance of OH groups around 3500 cm⁻¹, the absorbance increased drastically above 7.0 × 10¹² ions/cm², above which track overlapping became significant. It has been considered that OH groups were formed by the radio-oxidation. Therefore, oxygen molecules and “a certain level” of radical mobility would be necessary. However, the present study was performed under vacuum at 16 K, at which very low oxygen concentration and low radical mobilities were expected, thereby it would be hard to consider OH groups were formed by radio-oxidation. The other interpretation to form OH groups was reactions between oxygen radicals created by radiation damage to carbonate ester or ether moieties and hydrogen atoms released from CH groups. Below 7.0 × 10¹² ions/cm², each latent track had enough distance. When the track overlapping becomes significant, the distance between some tracks became close. In that case, it could be possible that oxygen radicals sometimes reacted with hydrogen atoms, when they were in close locations due to the track overlapping. Thus, not only radical mobilities but also latent track structure was also an important factor to form OH groups as new ending groups.

## Roles of radical and molecular mobility

The absorbance of OH groups was firstly constant up to 180 K. Above 180 K, the absorbance began increasing monotonically. This finding demonstrated that “a certain level” of radical mobility was mandatory to form OH groups, which were formed reactions between oxygen radicals and hydrogen atoms. We also confirmed the increase of CO2 molecules with increasing annealed temperature. The absorbance assigned to CO2 molecules increased monotonically with increasing the temperature. To quantitatively discuss the relation of intermediate species and yields for typical functional groups lost with yields of CO2 molecules, additional experiments using thinner PADC film (< 3 µm) are crucial. This is because we can obtain unsaturated IR spectra for any functional groups in PADC when the thinner PADC films are used for experiments. However, unfortunately, we did not have enough beam time in 2023 due to the accelerator trouble. However, in the 2024 beam time (July 13th to 17th), we have successfully conducted experiments to give answers to the relation between yields of CO2 molecules and typical functional groups lost in PADC. We are now carefully analyzing obtained spectra.
### 3. Determination of absolute singly and doubly cross-section of emitted electrons from biomolecules upon carbon ion collision

**Experiment number: P1230**

**Date: April 22-24, 2023**

**Spokesperson and co-authors**

Violaine VIZCAINO (CIMAP)
Suvasis SWAIN (CIMAP)
Alain MERY (CIMAP)
Jean-Yves CHESNEL (CIMAP)

**Abstract**

We measured ion-induced electron emission from DNA base Adenine and RNA base uracil using a newly developed experimental set-up based on velocity map imaging (VMI) technique. This technique allows measuring, at once, all electrons emitted in a solid angle of $4\pi$ steradians with energy as low as a few tenths of eV up to 200eV. By monitoring the target density, projectile ion beam intensity and the beams overlap with the use of a quartz crystal micro balance and an ion beam profiler, we were able to estimate absolute singly- and doubly-differential cross sections for electron emission. We measured these absolute cross sections for collision with carbon ion beam with energy from 0.95 MeV/u (IRRSUD beamline) to 13.7 MeV/u (SME beamline)

**Experiment report**

Electron emission following ion collisions with atoms or molecules has been studied for several decades. Electron emission from the target, projectile or both, electron transfer or electron interference have been the subject of numerous experimental and theoretical studies. Measuring the electron yield as a function of energy allows a better understanding of the main ionization mechanisms, from soft collisions producing low energy electrons to binary collisions or inner-shell ionization producing well defined peaks at high energy. In more recent years, ion collision with biologically relevant molecules has received increasing interest due to applications to radiation biology. Indeed, the use of ion beams (protons or carbon ions) is increasingly employed in medicine for the treatment of cancer. Ion beam therapy, unlike conventional radiotherapy, allows a better localization of the energy deposition in the tissue due to the intrinsic properties of ion propagation through matter. Studies of the collision between multiply charged ions and molecules in the gas phase help understanding the fundamental mechanisms involved at the molecular level (fragmentation, electron emission). With this experiment, we contributed to this general endeavour by measuring absolute cross section from DNA/RNA. With our new set-up based on the velocity map imaging technique, we were able to measure electrons with low energy and all emission angle (including forward and backward emission) unlike conventional technique using electrostatic analyser.

The projectile ion beam from either IRRSUD or SME beamlines is shaped by a series of slits before entering the collision chamber. Its intensity and position are monitored by a Faraday cup and an ion beam profiler, respectively, located after the collision chamber. The target beam is produced with a two-stage effusion cell and shaped by two consecutive skimmers before entering the collision chamber where it crosses orthogonally the projectile ion beam. A pneumatic push-pull shutter is placed between the two skimmers to block the target beam in order to measure the background (i.e. electrons from the residual gas) which is subtracted latter on. After crossing the collision chamber, a quartz crystal microbalance allows monitoring the mass flux of the target beam and thus obtaining the beam density. The electrons created in the collision region are extracted by a homemade multi-electrode VMI spectrometer and detected by a position sensitive detector constituted of two microchannel plates (MCPs) and a phosphor screen. The images are recorded with a camera: they represent the 2D projection of the electron cloud produced by the ionization of the target. Therefore, by applying an inverse Abel transform we can reconstruct the velocity distribution (kinetic energy and emission angle) of the emitted electrons. Absolute cross sections $\sigma$ (expressed in cm$^2$ in the following) can be determined by normalizing the count rate of detected electrons $N_e$ (electrons.s-1) by the detector efficiency $\epsilon$, the count rate of projectile ions $N_p$ (ions.s-1), the density of the target beam $\rho$ (molecules.cm-3) and the length of the interaction region l (cm): $\sigma = N_e-/(\epsilon N_p \rho l)$. In order to study the kinetic energy (E) dependence and/or angular ($\Omega$) dependence of electron emission, differential cross sections $d\sigma/dE$, $d\sigma/d\Omega$ or $d^2\sigma/dEd\Omega$ can be determined after analysis of the inverse Abel transform of the detector
image. The inverse Abel transform numerically reconstructs a cylindrically symmetric 3D object (emitted electrons) from its 2D projection on a plane (detector) parallel the axis of symmetry (projectile ion beam). Electron emission has indeed a cylindrical symmetry along the projectile beam, which means that it does not depend on the azimuthal angle $\phi$. The angular dependence of the cross section is usually expressed as a function of $\theta$, the polar angle defined with respect to the projectile ion beam.

Integral cross sections have been determined by integrating the single differential cross sections ($d\sigma/dE$ or SDCS(E)) between 0.2 eV and 100 eV for both Uracil and Adenine upon collision with both 0.95 MeV/u $C^{4+}$ and 13.7 MeV/u $C^{5+}$. In the figure below (left panel), we compare our values (normalized by $q^2$, $q$ being the projectile charge state) for Uracil to both experimental and theoretical cross sections from the literature. As expected, the determined cross section is lower for 13.7 MeV/u $C^{5+}$ than for 0.95 MeV/u $C^{4+}$. Indeed, as the projectile ion velocity increases, the interaction time between the target electron and the projectile ion and therefore the ionization cross section decreases as well. However the values measured seems to be a bit higher that the theoretical model or experimental results while the previous measurement on IRRSUD beamline with 0.95MeV/u $C^{4+}$ had reasonably good agreement with the literature. The same trend is also found for Adenine. For adenine we also have measured the cross section for 13.7 MeV/u $C^{6+}$ using the stripper from SME beamline and confirm de $q^2$ dependence of the cross section.

To study the angular dependence of the electron emission, one can plot the absolute doubly differential cross sections DDCS(E,θ) i.e. $d^2\sigma/dEd\Omega$ (E, θ) that can be deduced directly from the inverse Abel transform of the detector images. However, due to the poor statistics, we rather plot here the absolute SDCS(E) integrated on a specific angular range $\Delta\theta$, noted SDCS$_{Δ\theta}$(E). In the figure below (right panel), the SDCS$_{Δ\theta}$(E) are determined for three angular ranges $\Delta\theta$ to highlight the forward emission [0 : $\pi$/3], backward emission [2$\pi$/3:$\pi$] and orthogonal emission [$\pi$/3 : 2$\pi$/3]. In the figure, we can see that below 1eV, the forward and backward emission are roughly of the same magnitude. Between 1 eV and 10 eV, we observe a break of the forward/backward symmetry as the forward emission increases to reach the orthogonal emission magnitude above 10 eV. This increase of forward emission is characteristic of two-center electron emission where ejected electrons are attracted by the outgoing projectile ions. At higher projectile energy (not shown here) the electron emission present a similar angular distribution.

<figure><img src="image_161.png" /></figure>

### Legend

Absolute cross section for electron emission from Uracil in cm$^2$ determined for both 0.95 MeV/u $C^{4+}$ and 13MeV/u $C^{5+}$ are compared with theoretical models as well as other experimental data (left panel). Single differential cross section SDCS$\Delta\theta$(E) in cm$^2$/eV for electron emission from uracil upon 0.95-MeV/u $C^{4+}$ collision determined for three different angular ranges (right panel).
# 4. Flexible piezoelectric SHI-nanostructured composite generators undergoing large bulging deformation regime

Experiment number: P1358

Date: May 11-12, 2023

## Spokesperson and co-authors

Marie Sigallon¹, E. Sarrey¹, A.-L. Hamon, ², Adrien Baillard³, Vincent Consonni³, Florian Aubrit¹, Natalya Potrzebowska¹, Romain Grasset¹, Mohamed Tabellout³, Jean-Eric Wegrowe¹, Marie-Claude Clochard¹*

1. Laboratoire des Solides Irradiés, CEA/DRF/IRAMIS, Ecole Polytechnique, CNWS, Institut Polytechnique de Paris, F-91128 Palaiseau

2. Laboratoire de Mécanique Paris-Saclay, Université Paris-Saclay, CentraleSupElec, ENS Paris-Saclay, CNRS, F-91190, Gif-sur-Yvette, France

3. Laboratoire des Matériaux et du Génie Physique, Grenoble INP - CNWS, Minatec, 3, parvis Louis Néel, F-38016 Grenoble

4. IMMM, UMR CNWS 6283. Université du Maine - UFR Sciences et Techniques Avenue Olivier Messiaen 72085 Le Mans Cedex 9

## Abstract

There is a huge difference between piezoelectric polymer films and solid crystals for the application to piezoelectric generators. In the case of polymers, the optimal piezoelectric response imposes the large deformation regime. Starting from the linear Curie's constitutive equations, we have developed an analytical model under the assumption of the large bending and elongation regime. Such a regime resulted herein from bulge testing configuration that our newly mounted experimental set-up allows. This model showed a specific non-linear piezoelectric response, that followed a power 2/3 of the mechanical excitation:

$$|\vec{V}| = A(\ell) |\mathcal{F}_t[\delta p^{\frac{2}{3}}(t)](\omega)| \frac{\omega R}{\sqrt{1 + (\omega RC)^2}}$$

with $A(\ell) := A_p e_{31} \left(\frac{A_p}{\pi \ell^2}\right)^{\frac{1}{3}} \left(3\frac{1-\nu}{7-\nu}\frac{1}{Y}\right)^{\frac{2}{3}}$ in where $\omega$ is the angular frequency, $R$ the load resistance, $C$ the capacitance, $\delta p$ the overpressure, $A_p$ pressurized area, $\ell$ time, $\ell$ the piezopolymer or composite thickness, $e_{31}$ the piezoelectric constant, $\nu$ the Poisson's coefficient, $Y$ the young modulus. The experimental results carried out on piezoelectric pure PVDF films and SHI-nanostructured Ni NWs/PVDF composites validated the model.

To test the validity domain of such a model, peculiar SHI-nanostructured PVDF-based ZnO composites was also successfully synthesized and tested under the bulge deformation applied by this new experimental set-up. The beneficial effect of hydrothermal process on the morphology and piezoelectric performance of zinc oxide/polyvinylidene fluoride (ZnO-PVDF) composite thin membranes (10µm thick) was demonstrated. Vertically aligned ZnO nanowires were epitaxially grown inside the cylindrical nanoporosity of an ion-track-etched polarized PVDF to form flexible ZnO-PVDF composite piezomembranes. Swift-Heavy Ions (SHI) were firstly used to irradiate polarized PVDF thin films. A subsequent chemical etching in alkaline media created dense and statistical arrays of cylindrical nanopores (10⁹ cm⁻²). These nanoporous piezoelectric PVDF membranes, before and after hydrothermal reaction, were characterized by scanning electron microscopy (SEM, TEM), atomic force microscopy (AFM), reflectance spectroscopy and dielectric measurements. Results demonstrated that under mild hydrothermal reaction conditions, produced ZnO nanowires exhibited an ideal microstructure for piezoelectric performances, i.e. hexagonal wurtzite structure. Such a structure plays an important role in the resulted piezoelectric capacity of ZnO-PVDF composite membranes. From piezoelectric analysis in bulging mode, the output power was plotted against 8 load resistances ranging from 10⁵ to 10⁷ Ω, exhibiting a maximum at 2.10⁶ Ω. It was found that the maximum of the output power can also be modelled using our analytical model and found to be 28% higher in presence of these embedded ZnO nanowires of high aspect-ratio in low mechanical excitation frequency region ranging from 4 to 26 Hz. It thus demonstrates a very promising potential in the renewable energy application of electromechanical energy conversion.

<footnote>*spokesperson</footnote>
Experiment report

<table><tr><td>Beam-line</td><td>IRASME</td></tr><tr><td>Ion</td><td><sup>86</sup>Kr<sup>28+</sup></td></tr><tr><td>Flux max</td><td>10<sup>6</sup> ions/(cm<sup>2</sup>.s)</td></tr><tr><td>Fluences</td><td>10<sup>7</sup> -10<sup>8</sup>-10<sup>9</sup>-10<sup>10</sup> ions.cm<sup>-2</sup></td></tr><tr><td>Atmosphere</td><td>He [A 'tromblon' is needed to change the atmosphere of the irradiation chamber]</td></tr><tr><td>Holder</td><td>Classical aluminium plates</td></tr><tr><td>Surface</td><td>4x30= 120 cm<sup>2</sup> per plate</td></tr><tr><td>Number of polymer bands stacking max per plate</td><td>3 for 10µm thick films, 1 for films > 10µm (herein 28 to 100 µm)</td></tr><tr><td>Number of irradiation runs</td><td>22</td></tr><tr><td>Total of irradiated polymer bands</td><td>12x3+1x2+9x1=47 bands</td></tr></table>

IRASME line at GANIL is necessary to get sufficient energy to cross the entire thickness of piezoPVDF films (10 and 28µm) without any difference in the deposited energy on both side. Superimposed polymer bands of 4x30 cmxcm are stuck on the sample holder for each irradiation run. No modification of existing holders was done. He atmosphere helped in limiting temperature increase during irradiation to avoid any depolarization of piezoelectric polymers.

For evaluation of piezoelectric performances, we have recently developed a dedicated experimental set-up at LSI (Fig. below). Its specificity is to apply cyclically a quasi-perfect sinusoidal deformation to the part of piezoPVDF membrane exposed to the strain. The tested polymer or composite films are clamped inside the circular chamber which provokes a bulge deformation under air overpressure.

<figure><img src="image_162.png" /><figcaption>Photo of experimental set-up for piezoelectric study of PVDF-based piezomaterials in shape of thin films</figcaption></figure>

<figure><img src="image_163.png" /><figcaption>Typical output voltage and pressure signal profiles obtained for a 10µm-thick piezoPVDF film.</figcaption></figure>
<figure><img src="image_164.png" /><figcaption>Figure</figcaption></figure>

Legend

SHI-nanostructured ZnO NWs/piezoPVDF composite membranes synthesized by hydrothermal bath processing –
A. 3D AFM image of a cross-section showing a completely-filled ion-track etched PVDF membrane with ZnO NWs;
B. TEM image and its figure of diffraction of a piece of ZnO in an etched piezoPVDF track;
C. Scheme displaying the bulge testing configuration of our experimental set-up at LSI to measure piezoelectric response of flexible piezomaterials and the transformation of a circular membrane of radius $\sqrt{A_p/\pi}$ due to an overpressure $\delta p$ inside the chamber. Cylindrical coordinates (r, $\varphi$, z) are used. $\omega$ stands for the z-component of the displacement field for any point of polar coordinates (r, $\varphi$), and $\omega_{max}$ its maximum value reached at the center $r=0$;
D. Output voltage time traces of the piezoelectric responses of piezoPVDF, track-etched piezoPVDF and nanostructured piezoPVDF with ZnO NWs.
# VI. IRRSUD

<figure><img src="image_165.png" /></figure>
# 1. Chemical evolution of PAH astrophysical ices induced by heavy ion irradiations

Experiment number: P1319

Date: April 2023

## Spokesperson and co-authors

Spokesperson: de Barros, Ana Lucia Ferreira (CEFET-RJ, Rio de Janeiro, Brazil)

Boduch, Philippe (CIMAP, UNICAEN)

Bychkova, Anna (CIMAP, UNICAEN)

Da SILVEIRA, Enio (Van de Graaff Lab, Physics Department, Rio de Janeiro, Brazil)

Domaracka, Alicja (CIMAP, CNRS)

Pires da Costa, Cintia (CIMAP, ENSICAEN)

Rothard, Hermann (CIMAP, CNRS)

Ricca, Alessandra (Carl Sagan Center, SETI Institute & NASA Ames Research Center)

## Abstract

Samples of α-pinene ice were irradiated at 10 K by 61.3 MeV $^{84}$Kr$^{15+}$ ions to simulate the effects of heavy ion cosmic ray bombardment on chiral molecules in the interstellar medium. Their chemical evolution was monitored by mid-infrared Fourier transform (FTIR) spectroscopy to follow the reaction products and to determine the extent of racemization. This successful pinene irradiation experiment was started in 2022 with a Kr beam and pursued with a Fe beam in 2023.

## Experiment report

Radiolysis of α-pinene by 61.3 MeV $^{84}$Kr$^{15+}$ ions was analysed with the scope to simulate the effects of heavy ion cosmic ray bombardment on chiral molecules in the interstellar medium. The α-pinene ice samples were irradiated at 10 K and their chemical evolution was monitored by mid-infrared Fourier transform (FTIR) spectroscopy to characterize the reaction products and to determine the extent of racemization. The integrated band strengths have been obtained for all the neutral α-pinene vibrational bands using the experimental band integrated absorbances and the theoretical absolute intensities calculated along the column densities.

In the current heavy ion bombardment experiments, small molecules were formed and the precursor, α-pinene, was destroyed instead of being racemized. Twelve hydrocarbons were produced (final fluence of 2.0 × 10¹² ions cm⁻²): methane (CH₄), acetylene (C₂H₂), ethylene (C₂H₄), propylene (C₂H₆), propane (C₃H₈), n-butane (C₄H₁₀), butene (C₄H₈), propyne (C₃H₄), benzene (C₆H₆), ethane (C₂H₆), vinylacetylene (C₄H₄), and 2-methyl-1,3-butadiene or isoprene (C₅H₈). The highest formation cross-section (~40 × 10⁻¹⁵ cm²) was observed for the C₃H₄, and the lowest was for C₃H₈ (~3 × 10⁻¹⁵ cm²).

The radiochemical yields for these molecules follow the same trends as those of their cross-sections. The atom budget calculation confirms that all the expected products have been generated during the radiolysis and supports the conclusion that the proposed A values are accurate. The α-pinene sputtering yield for this ion beam was found to be Y₀ = 1.84 × 10⁶ molecules per impact.
<figure><img src="image_166.png" /><figcaption>Fig. 1. The column density N of pinene as a function of projectile fluence F follows the function N(F) = (N₀–Y₀F) exp(–σdF). The values of the destruction cross section σd, of the sputtering yield Y₀ and of the initial column density N₀ are given in the figure 1.</figcaption></figure>

ACKNOWLEDGEMENTS

ALF de B and EF da S acknowledge the Brazilian organizations CAPES, CNPq (Bolsa de Produtividade 307418/2021-9 and 30.4511/2022-6) and FAPERJ (E-26-210.965/2021, E-26-210.801/2021, E-26-245.307/2019, E-26-202.549/2019, E-26/201.934/2019, E-26-200.320/2023, and E-26/201.622/2023). AR acknowledges support from the NASA's Solar System Workings program (SSW; 80NSSC21K0776). We also acknowledge support by the Region Normandie (RIN SCHINOBI) including a post grant for CAPdC. The experiment was performed at Grand Accélérateur National d'Ions Lourds (GANIL) by means of CIRIL Interdisciplinary Platform, part of CIMAP laboratory, Caen, France.

**Reference:** A. L. F. de Barros, A. Ricca, A. Bychkova, Cíntia Pires da Costa, P. Boduch, H. Rothard, E. F. da Silveira, A. Domaracka, Heavy ion radiolysis of the chiral terpene α-pinene, Monthly Notices of the Royal Astronomical Society MNRAS 530 (2024) 2181–2198 doi: 10.1093/mnras/10.1093/stae757
## 2. Self-healing of nuclear glass alteration gels under irradiation

Experiment number: P1254, P1263

Date: May and June 2023

### Spokesperson and co-authors

de Laharpe Pierre, Deschanels Xavier (UMR 5257 ICSM/LNAR)

### Abstract

In the context of elucidating the role of water in the long-term behavior of vitrified nuclear waste, understanding the microstructural evolution of the glass alteration gel under irradiation remains necessary. In particular, the porous network present in the gel may collapse when irradiated. Concomitantly, the collapse of mesoporous silica under various irradiation regimes was recently monitored using X-ray scattering techniques. In this study, mesoporous silica thin films derived from the synthesis of SBA-15 and MCM-41 were prepared via sol-gel dip-coating. Some were immersed for several days in silica-enriched water and irradiated in the electronic regime by Xe (E = 92 MeV) and Ne (E = 20 MeV) ions. Results exhibit a mild reduction of pore collapse when samples with thinner pore walls are immersed prior to irradiation compared to dry samples, suggesting some degree of interaction between water and pore walls. Further experiments and analysis tools are called for.

### Experiment report

Deep geological disposal of high-level nuclear waste is envisioned for the French CIGEO future repository site, where glass was chosen to compose the immobilization matrix of radionuclides. The parameters affecting its long-term durability include self-irradiation and aqueous alteration due to groundwater. Studies conducted on simplified borosilicate compositions found that ballistic damage tends to increase the formation of the alteration gel [1], which can feature nanometer scale pores and open channels [2]. Other recent results combining irradiation after alteration showed a possible competing phenomenon, as the gel's porous microstructure collapsed when irradiated [3]. The mechanisms surrounding this process, especially the possible role of water, are yet to be determined. Monitoring the collapse of a gel's random porous microstructure is experimentally challenging, as it typically requires TEM imaging throughout the irradiation episode. In this work, we address this point by using SBA-15 and MCM-41 as model materials.

Mesoporous silica thin films were dip-coated on silicon substrates. Initial solutions were prepared from tetraethylorthosilicate (TEOS) in two steps according to reference [4]. They were later aged at 80°C and calcinated at 400°C for 7 h. Calcinated thin films using P123 and CTAB were respectively noted IPc and ICc. The essential structural descriptors of mesoporous silica thin films are $d_{inter}$, defined as the distance between two layers of pores in the film (with $d_{inter} = d_{pore} + t_{wall}$, respectively the pore diameter and the pore wall thickness), and $d_{tot}$ the total thickness of the film, they were extracted from Kiessig fringes and pseudo-Bragg peaks measured by X-Ray Reflectivity at, according to method from reference [5]. IPc films feature a 2D hexagonal network of cylindrical pores, while in ICc films they are spheres arranged hexagonally in 3D [4]. Dissolution processes in the immersion water were kept to a minimum by cooling down and filtering a [Si] = 200 mg/L solution prepared at 90°C, pH90°C = 9 to ensure near saturation at 25 °C. Samples of thin films (ICc, IPc) were immersed in 1.75 mL individual volumes of this solution for durations ranging from 2 to 5 days. Before irradiation, they were left to dry for 1h in open air and characterized. Because additional drying is expected from the vacuum in the irradiation chamber, "control" immersed samples were placed in the chamber but not irradiated. One series of IPc samples immersed 4 and 5 days was also enclosed in an airtight sealed cell behind a 8 µm thick Al foil in the irradiation chamber to retain a few drops of the immersion water while irradiated by Xe ions. They are indicated by semi-hollow symbols on Fig. 1. In this series, the presence of water could be visually confirmed after irradiation for fluences $1-2 \times 10^{13}$ ions.cm$^{-2}$. Irradiations were performed at room temperature on the IRRSUD beamline of GANIL in a $\approx 10^{-6}$ mbar vacuum chamber. The beams were respectively Xe-92 MeV and Ne-20 MeV. Due to a specific experimental design and in order to maintain comparable damage across the experiment, all samples (except "dry non-immersed" samples in Ne irradiations) were shielded by 9 µm-thick (for Ne irradiation) and 8 µm-thick (for Xe irradiation) aluminum foil screens. For all samples the ion beam is perpendicular to the surface, and therefore perpendicular to the cylindrical pores. The effective projectile energy and the corresponding stopping powers in 2.2 g.cm$^{-3}$ SiO$_2$ (representing the density of the silica walls, which is considered the same as amorphous silica), after traversing
the screens were calculated using data available in the SRIM/TRIM 2013 software. In both cases, the electronic
contribution is largely dominant. Due to the very small thickness of material traversed by the beam, the total
stopping power is assumed to be constant and the deposited energy is estimated as : deposited energy = total
stopping power × fluence. Table 2 summarizes the ion beams' characteristics, including sputtered ion yields
obtained by calculations on 10⁴ ion projectiles accumulated in TRIM (mode: monolayer collision steps/surface
sputtering, with surface, binding and displacement energies as tabulated in the software).

Figure 1 summarizes the variation of structural descriptors for all experiments, displayed on a common axis accounting for the deposited energy. Since the chosen immersion duration range did not allow a clear discrimination between immersed samples series, they were grouped for readability and compared to the dry ones. An asymptotic exponential function is fitted on the $d_{tot}$ variation plots to help qualitatively discriminate the sample series. This fit is made under the assumptions that the thickness variation reaches a saturation value (equal to the initial porosity, typically 40 % for IPs and 35 % for ICc [4]) and that the change in thickness is proportional to the damaged volume (Marples model [6]). This fit was not performed on the $d_{tot}$ plots due to insufficient data outside the uncertainty range. For all sample series, pore collapse does not significantly occur before ≈ 1-2.10²¹ keV.cm⁻³, consistent with previous observations made on such samples [7-8]. Both immersed and non immersed IPs samples show similar collapse, reaching up ≈ 30 % $d_{tot}$ at ≈ 10²² keV.cm⁻³ and ≈ -40 % $d_{inter}$ at ≈ 10²² keV.cm⁻³. In the Xe irradiation series, ICc dry samples exhibit up to 25 % $d_{tot}$ and 11 % $d_{inter}$ decreases at 3x10²¹ keV.cm⁻³ of deposited energy, against 15 % $d_{tot}$ and negligible $d_{inter}$ decreases for immersed ICc samples at the same energy. The fitted curves for the Ne irradiation series suggest a similar tendency.

Based on the evolution $d_{tot}$ and $d_{inter}$, the collapse of the porous structure under irradiation seems mildly mitigated for ICc immersed samples. The absence of such a phenomenon for IPs samples might be primarily due to their greater pore wall thickness (typically 2-3nm against 1nm), rendering them less sensitive to the immersion prior to irradiation. Three IPs and two ICc samples above 10²¹keV.cm⁻³ of deposited energy irradiated by Xe ions (against only on ICc for Ne ions) did not allow the extraction of $d_{inter}$, indicating that the structure is too damaged, therefore limiting the interpretation from the $d_{inter}$ plots. This is unlikely a result of sputtering, as fluctuations of the ratio (estimating the number of porous layers) are comparable between the ion beams despite much higher sputtering yields for Xe (Table 2). However, the electronic stopping power of Xe (4.71 × 10⁻⁷ keV.cm⁻¹) being well above the track formation threshold [9] could better explain this stability discrepancy. Both structural descriptors show an overall increase for control samples. While it suggests a swelling of thin films upon immersion and vacuum drying, it doesn't exceed 5% in value, rendering the preimmersion and post-immersion structures quite comparable. Under irradiation, the various immersion durations sample series could not be distinguished one from another. Additional immersion throughout irradiation (samples enclosed with water in the airtight cell) did not appear a relevant parameter either. The observed collapse reduction is overall greater when the deposited energy (and time spent in the vacuum chamber, thus eliminating any remaining water of samples that were only immersed before irradiation) increases. Albeit difficultly interpretable with only the descriptors and the experimental conditions used in this study, these observations preferably indicate an interaction effect of pore walls with water prior to irradiation over an energy dissipation by remaining pore water. Mesoporous silica are metastable materials and can continue to evolve even in saturation conditions. Gouze et al. [10] identified several possible mechanisms while studying the aqueous alteration of MCM-41 and SBA-15 powders at 50°C. It is well conceivable that a higher degree of hydration (increased time and temperature) on both types of samples might better highlight the reported phenomenon and allow its quantification.
<figure><img src="image_167.png" /><figcaption>Fig. 1. Evolution of the (a) total thickness ddot and (b) interlayer distance dinter of IPC thin films and (c) total thickness ddot and (d) interlayer distance dinter of ICc thin films under irradiation. For Xe immersed samples of graph (b) and (d), variations are calculated between the final state and the initial pre-immersion state. The area filled in light blue indicates the estimated uncertainty range from fluctuations of control samples, which were immersed and placed in the irradiation chamber but not irradiated. Missing data points at high deposited energies on graphs (c) and (d) correspond to sample for which dinter could not be extracted from the XRR profile.</figcaption></figure>

<table><caption>Table 1 – Thin films characteristic</caption><thead><tr><th rowspan="2">Thin film</th><th colspan="5">Initial structure</th></tr><tr><th>d<sub>tot</sub><br>(nm)</th><th>d<sub>inter</sub><br>(nm)</th><th>d<sub>pore</sub><br>(nm)</th><th>t<sub>wall</sub><br>(nm)</th><th>Morphology of pores</th></tr></thead><tbody><tr><td>ICc</td><td>85-100</td><td>3.3-3.9</td><td>~2-3</td><td>~1</td><td>3D, spheres</td></tr><tr><td>IPc</td><td>50-65</td><td>5.5-7.0</td><td>~4</td><td>~2-3</td><td>2D, cylinders</td></tr></tbody></table>

<table><caption>Table 2 - Characteristics of the ion beams</caption><thead><tr><th rowspan="2">Ion beam</th><th rowspan="2">Average flux<br>(ions.cm<sup>-2</sup>.s<sup>-1</sup>)</th><th rowspan="2">Min. and max.<br>fluences<br>(ions.cm<sup>-2</sup>)</th><th colspan="3">Beam energy (MeV)</th><th rowspan="2">Stopping<br>(keV.cm<sup>-1</sup>)</th><th rowspan="2">power<br>(keV.cm<sup>-1</sup>)</th><th colspan="2">Sputtered ion yield<br>(atoms.ion<sup>-1</sup>)</th></tr><tr><th>Before Al<br>foil</th><th>After Al<br>foil</th><th>Al<br>foil</th><th>Electroni<br>c</th><th>Ballistic</th><th>Si</th><th>O</th></tr></thead><tbody><tr><td>Ne (non<br>immersed)</td><td>6x10<sup>9</sup></td><td>3.0x10<sup>12</sup><br>9.4x10<sup>14</sup></td><td>–</td><td>20</td><td></td><td>2.16x10<sup>7</sup></td><td>2.98x10<sup>5</sup></td><td>0.006</td><td>0.018</td></tr><tr><td>Ne</td><td>6x10<sup>9</sup></td><td>3.0x10<sup>12</sup><br>9.4x10<sup>14</sup></td><td>–</td><td>20</td><td>0.61</td><td>6.84x10<sup>6</sup></td><td>4.76x10<sup>5</sup></td><td>0.083</td><td>0.274</td></tr><tr><td>Xe</td><td>4-5x10<sup>9</sup></td><td>5.0x10<sup>12</sup><br>1.0x10<sup>14</sup></td><td>–</td><td>92</td><td>17.7</td><td>4.71x10<sup>7</sup></td><td>3.3x10<sup>6</sup></td><td>0.446</td><td>1.37</td></tr></tbody></table>
Legend

[1] A. Jan, J. Delaye, H. Kaya, S.H. Kim, A.H. Mir, T. Charpentier, F. Angeli, S. Gin, Int. J. Appl. Glass Sci. 14 (2023) 113-132.
https://doi.org/10.1111/ijag.16618.

[2] S. Gin, M. Collin, P. Jollivet, M. Fournier, Y. Minet, L. Dupuy, T. Mahadevan, S. Kerisit, J. Du, Nat. Commun. 9 (2018) 2169.
https://doi.org/10.1038/s41467-018-04511-2.

[3] A.H. Mir, A. Jan, J.-M. Delaye, S. Donnelly, J. Hinks, S. Gin, Npj Mater. Degrad. 4 (2020) 11.
https://doi.org/10.1038/s41529-020-0115-0.

[4] Sandrine Dourdain "Caractérisation structurale, poreuse et mécanique de films minces de silice mésoporeuse : influence de la fonctionnalisation", thèse 2006. http://www.theses.fr/2006LEMA1020.

[5] A. van der Lee, Solid State Sci. 2 (2000) 257-278. https://doi.org/10.1016/S1293-2558(00)00119-9.

[6] J.A.C. Marples, Nucl. Instrum. Methods Phys. Res. B 32 (1988) 480-486. https://doi.org/10.1016/.

[7] Y. Lou, S. Dourdain, C. Rey, Y. Serruys, D. Simeone, N. Mollard, X. DeschANELS, Microporous Mesoporous Mater. 251 (2017) 146-154. https://doi.org/10.1016/j.micromeso.2017.05.057.

[8] J. Lin, G. Toquer, C. Grygiel, S. Dourdain, Y. Guari, C. Rey, J. Causse, X. Deschanel, Microporous Mesoporous Mater. 328 (2021) 111454. https://doi.org/10.1016/j.micromeso.2021.111454.

[9] S. Klaumünzer, Nucl. Instrum. Methods Phys. Res. Sect. B Beam Interact. Mater. At. 225 (2004) 136-153.
https://doi.org/10.1016/j.nimb.2004.05.014.

[10] B. Gouze, J. Cambedouzou, S. Parrès-Maynadié, D. Régiscoul, Microporous Mesoporous Mater. 183 (2014) 168-176.
https://doi.org/10.1016/j.micromeso.2013.08.041
## 3. Energetic ion processing of carbonaceous molecule icy mantles: destruction and formation of new species

Experiment number P1322

Date April 2023

### Spokesperson and co-authors

Alicja Domaracka (CIMAP, Caen France)

Anna Bychkova (CIMAP, Caen, France)

Philippe Boduch (CIMAP, Caen, France)

Hermann Rothard (CIMAP, Caen, France)

Cintia Aparecida Pires da Costa (CIMAP, Caen, France)

Ana Lucia Ferreira de Barros (CEFET-RJ, Rio de Janeiro, Brazil)

### Abstract

Over the last decades it became clear that we live in a "molecular universe". Carbon forms the basis of the majority of the molecular species so far having been identified in space. Although small carbon-based molecules, like CO and CO₂, are among the most abundant molecules in space, only a small fraction of carbon is expected to be locked up in such species. It was proposed that a large fraction (up to 20%) of the interstellar carbon is built in polycyclic aromatic hydrocarbons (PAHs) and fullerenes. Several laboratory studies were carried out to investigate the effects of vacuum ultraviolet photolysis on PAH:H₂O ices. However, data about interaction of energetic ions (cosmic rays) with PAH ices are very scare. Therefore, we investigated effects induced by ion irradiation of pure pyrene ice at 10 K and of its mixtures with water. The aim is to obtain molecule destruction cross sections and to identify formation of new species.

### Experiment report

PAHs are important carbon carriers in space, playing a significant role in galaxy evolution and planet formation. Although PAHs with sizes ranging from C₅₀ to C₁₀₀ are reported to be the most common in space (Allamandola, et al., 1989), smaller PAHs may also survive in icy grain mantles. In the present studies, pyrene molecule (C₁₆H₁₀) was selected as a PAH representative. Pyrene was commonly detected in meteorites (Elsila, et al., 2005), (Basile, et al., 1984) and identified in the UV spectra of P/Halley comet (Clairemidi, et al., 2004). The possible formation pathway of pyrene from the reaction of 4-phenanthrenyl radical ([C₁₄H₉]⁺) with acetylene (C₂H₂) in carbon-rich circumstellar environment was demonstrated in the work (Zhao, et al., 2018).

Samples of pure pyrene ice and mixed pyrene-water ices were irradiated at 10 K by 39.2 MeV⁵⁶Fe¹⁰⁺ ions to simulate the effects of heavy ion cosmic ray bombardment of carbonaceous molecules in the interstellar medium (for experimental details see table below). The experiments were conducted with the UHV IGLIAS set-up. Pyrene films were prepared by an evaporation of the commercial pyrene power (Merk) in a home made oven kept between 120-190°C. To prepare mixed ices, water vapor were injected in to main UHV chamber during pyrene deposition.

<table><thead><tr><th>Percentage of pyrene, %</th><th>Ion</th><th>Energy, MeV</th><th>T<sub>dep</sub>, K</th><th>T<sub>irr</sub>, K</th><th>Electronic stopping power, keV/µm</th><th>Nuclear stopping power, keV/µm</th><th>Penetration depth, µm</th><th>Column density of pyrene (10<sup>17</sup> cm<sup>-2</sup>)</th><th>Column density of water (10<sup>17</sup> cm<sup>-2</sup>)</th><th>Initial thickness of the sample, µm</th></tr></thead><tbody><tr><td>0,3</td><td rowspan="4">⁵⁶Fe¹⁰⁺</td><td rowspan="4">39,20</td><td rowspan="4">10</td><td rowspan="4">10</td><td>4360</td><td>13,86</td><td>16,60</td><td>0,057</td><td>17,13</td><td>0,56</td></tr><tr><td>2,3</td><td>4342</td><td>13,68</td><td>16,36</td><td>0,291</td><td>7,26</td><td>0,31</td></tr><tr><td>5</td><td>4572</td><td>14,23</td><td>15,58</td><td>0,196</td><td>3,07</td><td>0,15</td></tr><tr><td>100</td><td>5449</td><td>16,50</td><td>12,02</td><td>3,57</td><td>-</td><td>0,95</td></tr><tr><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>0,82</td><td></td><td>0,22</td></tr></tbody></table>
The chemical evolution under irradiation of samples was monitored by mid-infrared Fourier transform (FTIR) spectroscopy to characterize the reaction products and to determine destruction cross sections of pyrene. The destruction cross section of pyrene varies as a function of water concentration (see figure). Formation of several small hydrocarbons was observed: methane (CH₄), acetylene (C₂H₂), ethylene (C₂H₄), ethane (C₂H₆), allene (C₃H₄), benzene (C₆H₆), cyclopropane (c-C₃H₆), propane (C₃H₈), propylene (C₃H₆), propyne (C₃H₄). Additionally, in water mixed ices CO and CO₂ formation occurred.

The present results will be compared with data obtained with lighter projectiles like protons, He, C and S ions at ATOMKI facility (Debrecen, Hungary). This experiment was conducted in the frame of Anna Bychkova's thesis (deference mid of October 2024).

<figure><img src="image_168.png" /></figure>

## Legend

The aim of the experiment is to investigate pyrene evolution in pure and water mixed ices at 10K under analog of cosmic rays. On the right evolution of pyrene dissociation cross sections as a function of water concentration in the ice.

## ACKNOWLEDGEMENTS

ALF de B acknowledged the Brazilian organizations CAPES, CNPq (Bolsa de Produtividade 307418/2021-9 and 30.4511/2022-6) and FAPERJ (E-26-210.965/2021, E-26-210.801/2021, E-26-245.307/2019, E-26-202.549/2019, E-26/201.934/2019, E-26-200.320/2023, and E-26/201.622/2023). We also acknowledge support by the Region Normandie (RIN SCHINOBI) including a post grant for CAPdC. The experiment was performed at Grand Accélérateur National d'Ions Lourds (GANIL) by means of CIRIL Interdisciplinary Platform, part of CIMAP laboratory, Caen, France.
# 4. Processing of amino acids by swift ion beams/ Processing of amorphous and crystalline pyridine ices by MeV ion irradiation

Experiment number: P1337

Date: May 2023

## Spokesperson and co-authors

Cintia Pires da Costa

Alicja Domaracka (CIMAP, Caen France)

Anna Bychkova (CIMAP, Caen, France)

Philippe Boduch (CIMAP, Caen, France)

Hermann Rothard (CIMAP, Caen, France)

## Abstract

The occurrence of amino acids in meteorites and comets raises questions about how they have been formed in cosmic environments, as well as how long they can survive in outer space; radioresistance is essential information to predict half-lives and make advances on the origins of life studies. Furthermore, amino acid radiolysis is of Medical Physics interest. The main objective of the current work is to analyze, via infrared spectrometry, how destruction cross section of pure and water mixed amino acids exposed to energetic ion radiation depends on projectile's energy and sample temperature. We propose then, to examine the degradation of pure amino acids (e.g., glycine, phenylalanine and cysteine) by swift ions. The main goal is to verify the destruction cross section dependence on the beam stopping power and its possible applications for Astrochemistry and Medical Physics. The radioresistance of pyridine ice was probed under MeV ion beams irradiation by investigating the dependence of radiolysis and structural modifications as a function of projectile stopping power. The structural and chemical evolution of the samples as a function of projectile fluence was followed using infrared spectroscopy. All apparent destruction cross sections $\sigma_{d\text{ap}}$, which incorporate the effects of radiolysis induced molecule dissociation as well as the ejection of particles by sputtering, were measured. Initially crystalline pyridine ices present apparent destruction cross sections four times higher than amorphous ices. However, after amorphization is completed, the cross sections $\sigma_{d\text{ap}}$ of initially crystalline samples are equal to those of initially amorphous ices. At 130 K, pyridine is more radioresistant than at 10 K, with smaller destruction cross sections.

## Experiment report

Organic materials have been detected in meteorites and comets. The aminoacid glycine was observed in comet 67P/Churyumov-Gerasimenko by the Rosetta mission. This calls for inquiries into their formation processes within cosmic environments and their durability in outer space. Understanding the radioresistance of amino acids, for instance, is needed for estimating their lifespans and crucial for advancing research in fields such as astrobiology. Additionally, the radiolysis of amino acids holds significance in the realm of Medical Physics. We therefore propose to investigate the processing of pure and water mixed amino acids by swift ions, which are constituents of the radiation field in space. We focus on the dependence on the stopping power of the incoming ions. We intend to explore the degradation of various amino acids by infrared spectroscopy.

The experiments were planned to be conducted with the UHV IGLIAS set-up. Unfortunately, a technical problem with the oven of IGLIAS did not allow the production of amino acid films in situ for the measurements at the time. We spent hours trying to make a deposition of an amino acid film of glycine over a ZnSe substrate, thickness should be controlled by Fourier Transform Infrared spectroscopy - FTIR). We noticed that the oven was making the sample (which was in powder form) sublimate, because the blank window behind it became white after some time of "deposition". However, those gas phase molecules never arrived the substrate to form a film, probably due to some clogging in the tube between the oven and the substrate sample holder. We decided, then, to not waste the beam time and switched to the irradiation of ices of pyridine.

Amorphous and crystalline pyridine films were irradiated in the IGLIAS set-up. The evolution of column densities as a function of beam fluence (i.e. the accumulated number of projectiles per surface area irradiating the sample) was followed by FTIR in transmission mode. The measured pressures went from $1 \times 10^{-8}$ to $5 \times 10^{-10}$ mbar, where the first value represents the residual gas pressure during irradiation. Spectra were acquired at the Mid-IR regions (range 4000 – 600 cm$^{-1}$). Pyridine films, with thicknesses between ~ 0.2 and 10 µm (according to amorphous and
crystalline A-values measured by Hudson & Yarnall (2022) for the band 1031 cm⁻¹), were deposited onto ZnSe substrates at 10 and 130 K to make amorphous and crystalline pyridine ices, respectively. A commercially supplied sample of pyridine (liquid of 99.8% purity from Sigma Aldrich) was purified before using it in a series of freeze-pump-thaw cycles to remove air and other impurities volatile at liquid N₂ temperature.

The figure shows the dependence of the apparent destruction cross section, $\sigma_d^{ap}$, on the electronic stopping power, $S_e$, for seven different projectiles impinging on amorphous pyridine at low temperatures (10 - 15 K). As expected, the apparent destruction cross section of amorphous and crystalline pyridine samples increases with the increasing electronic stopping power. Compiling data from the present work, and from published studies [33, 10], a scaling law where $\sigma \sim a S_e^n$, with n = 1.25 is found. These data should help to estimate half-lives of pyridine ices in various cosmic environments.

<figure><img src="image_169.png" /></figure>

Legend

Amorphous (black squares) and crystalline (blue dots) pyridine apparent destruction cross section dependence on the electronic stopping power for different ion beams. The red line is a fitting of only amorphous data with the expression $\sigma_d^{ap} = a S_e^n$, where n = 1.25 and a = 8.1 × 10⁻⁵ cm² µm¹.²⁵ keV⁻¹.²⁵.
## 5. Surface microstructuring of single-crystal strontium titanate using swift heavy ions.

Experiment number: P1331

Date: June 14, 2023

### Spokesperson and co-authors

RAHALI Radia, GRYGIEL Clara, LEBIUS Henning, BENYAGOUB Abdenacer.

### Abstract

The modification of materials and the formation of defects caused by ion irradiation are the focus of several studies aimed at managing and improving their properties for various technological applications. Irradiation with ions of energy greater than 0.1 MeV/u gives rise to various modifications ranging from defects to amorphisation. At low fluence, where single ions prevail, each incident ion induces modifications that can be observable at the surface as craters, nano-hillocks, or chains of nano-hillocks, depending on the material characteristics and angle of irradiation [1-2]. As the intensity increases, we enter a regime of multiple ion impacts involving overlapping tracks. In the latter case, surface amorphization occurs in single crystal strontium titanate [3]. Previously, during other experiments conducted at the IRRSUD beamline at GANIL facility, wave-like structures on single-crystalline strontium titanate were observed [4]. The aim of this study was to assess the reproducibility of this phenomenon and, if it could be demonstrated to be reproducible, to identify the characteristics of these structures that could be controlled.

### Experiment report

In this study, swift heavy ions (SHI) at high fluences with a grazing incidence geometry were used to induce surface modifications on single crystal strontium titanate (STO). The analysis of the morphological change of the surface by means of atomic force microscopy (AFM) has shown a surface reorganisation with the formation of wave-like structures oriented perpendicular to the ion beam for the first for this material [4].

In order to investigate the effect of the different irradiation parameters on the modification of the strontium titanate (STO), a serie of irradiation were performed where the angle of irradiation and the fluence were varied.
92 MeV $^{129}$Xe$^{23+}$ ions beam on the IRRSUD beam-line were used. It correspond to an electronic energy loss at the surface to 21 keV/nm, which is well above the stopping power threshold of 12 keV/nm needed for track formation on the strontium titanate (SrTiO$_3$) sample [5].

The irradiation angle extends from the surface normal, decreasing until grazing incidence. The results showed that the angle affects the periodicity ($\lambda$) of the waves-like structures. While the angle increases towards the surface normal, the periodicity increases. Control over surface wave density is therefore possible with the angle.

The width of these structures is also impacted by the irradiation geometry. So, as the angle increases towards the surface normal, the waves grow larger (with an increasing period) and the more they extend parallel to the ion beam, the more they fill the area of a given surface. This has a direct impact on the valleys, whose size will therefore be reduced as the angle increases. At this point, the impact of the fluence is unclear since it was modified each time for the varied angles employed. Given this, research into the effect of fluence (the number of ions per unit area) was required to better understand the mechanism underlying this phenomenon and learn how to control it.
During this beam time, intermediate fluences were used as a baseline to compare the evolution of the surface wave structure obtained. The ion fluence at various grazing irradiation angles ranged from $1 \times 10^{13}$ ions cm$^{-2}$ to $4 \times 10^{14}$ ions cm$^{-2}$.

The analysis of the evolution of these structures with fluence indicated that the waves increased in height. The periodicity was unaffected by the fluence; thus, the number of waves remained constant while their size varied. In this approach, using higher fluences appears to increase wave growth, which can even result in very tiny pillar-shaped structures. To achieve a relatively thin structure and prevent its widening while increasing the irradiation angle towards the surface normal, it is necessary to increase the fluence.
<figure><img src="image_170.png" /></figure>

Evolution of the height (a) of waves of SrTiO3 (100) surfaces irradiated with 92 MeV Xe ions at 4° as a function of fluence. AFM image of SrTiO3 (100) surfaces irradiated at 4° with 92 MeV Xe ions at (b) $\phi = 4 \times 10^{13}$ ions cm$^{-2}$ and (c) $\phi = 1 \times 10^{14}$ ions cm$^{-2}$.

<footnote>[1] E. Akcöltekin, T. Peters, R. Meyer, A. Duvenbeck, M. Klusmann, I. Monnet, H. Lebius, M. Schleberger. Nature Nanotechnology 2 (2007) 290, 10.1038/nnano.2007.109.</footnote>

<footnote>[2] E. Akcöltekin, S. Akcöltekin, O. Osmani, A. Duvenbeck, H. Lebius, and M. Schleberger. New Journal of Physics, 10:053007, 2008.</footnote>

<footnote>[3] C. Grygiel, H. Lebius, S. Bouffard, A. Quentin, J. M. Ramillon, T. Madi, S. Guillous, T. Been, P. Guinement, D. Lelièvre, and I. Monnet. Review of Scientific Instruments, 83:013902, 2012.</footnote>

<footnote>[4] R. Rahali, H. Lebius, A. Benyagoub, E. Gardes, S. Guillous, I. Monnet, M. Sall, M.P. Chauvat, D. Marie, C. Grygiel. Materialia 27 (2023) 101696, 10.1016/j.mtla.2023.101696.</footnote>

<footnote>[5] M. Karlusic, S. Akcöltekin, O. Osmani, I. Monnet, H. Lebius, M. Jaksic, M. Schleberger. New J. Phys. 12 (2010) 043009, 10.1088/1367-2630/12/4/043009.</footnote>
# 6. Ion irradiation on solid phase silicate and organic matter, application for grain evolution in protoplanetary disks.

Experiment number: P1295-S-A

Date: March 8-10, 2023

## Spokeperson and co-authors

<table><tr><td>VINOGRADOFF Vassilissa (spokeperson)</td><td>PIIM, UMR CNRS 7345 - Centre Saint-Jérôme - case 252, Université d'Aix-Marseille, 13397 Marseille, France</td></tr><tr><td>DANGER Grégoire</td><td>PIIM, UMR CNRS 7345 - Centre Saint-Jérôme - case 252, Université d'Aix-Marseille, 13397 Marseille, France</td></tr><tr><td>DUVERNAY Fabrice</td><td>PIIM, UMR CNRS 7345 - Centre Saint-Jérôme - case 252, Université d'Aix-Marseille, 13397 Marseille, France</td></tr><tr><td>MINISSALE Marco</td><td>PIIM, UMR CNRS 7345 - Centre Saint-Jérôme - case 252, Université d'Aix-Marseille, 13397 Marseille, France</td></tr><tr><td>BODUCH Philippe</td><td>CIMAP-CIRIL-GANIL, BP5133, 14070 Caen Cedex 05, France</td></tr><tr><td>ROTHARD Hermann</td><td>CIMAP-CIRIL-GANIL, BP5133, 14070 Caen Cedex 05, France</td></tr><tr><td>SALL Mamour</td><td>CIMAP-CIRIL-GANIL, BP5133, 14070 Caen Cedex 05, France</td></tr><tr><td>DJOUADI Zahia</td><td>IAS-Université Paris Saclay, UMR CNRS 8617, Bât 120 – 121 Univ. Paris-Saclay, 91405 ORSAY CEDEX</td></tr><tr><td>BRUNETTO Rosario</td><td>IAS-Université Paris Saclay, UMR CNRS 8617, Bât 120 – 121 Univ. Paris-Saclay, 91405 ORSAY CEDEX</td></tr><tr><td>BAKLOUTI Donia</td><td>IAS-Université Paris Saclay, UMR CNRS 8617, Bât 120 – 121 Univ. Paris-Saclay, 91405 ORSAY CEDEX</td></tr><tr><td>HENAULT Elsa</td><td>IAS-Université Paris Saclay, UMR CNRS 8617, Bât 120 – 121 Univ. Paris-Saclay, 91405 ORSAY CEDEX</td></tr></table>

## Abstract

We propose in this new project to investigate the interaction of the silicate phase of interstellar dust grains with organic ices exposed to cosmic rays by a laboratory simulation with swift ion irradiation. The main objective of the project is to approach the evolution encountered by dust grains from interstellar medium to protoplanetary disk: is the organic matter in solid phase modified by the silicate phase? What are the main chemical modifications on the produced organic residue, leftover of the experimental process at room temperature? This project joins three laboratories that have different knowledge on the silicate or organic matter evolution in astrophysical environments. Such experiments will be performed for the first time and will bring new constraints to the organic- mineral interface/system that could exist in different solar system objects (comets, asteroids).

## Experiment report

The experiments have been discussed by the team prior the beginning of the beam time, in order to define properly which experiments will be performed, the distribution of the samples afterwards and the analysis. We decided that to start 3 days of experiments are enough, and the allocated time was in March 2023 due to covid restrictions and delay.

The experiments have been performed by Elsa Henault, Zahia Djouadi, Philippe Boduch, Hermann Rothard, Alicia Domaracka, Mamour Sall. Vassilissa Vinogradoff was not able to attend because she was sick.

During the three days of experiments, a series of experiments have been investigated with and without silicate on the windows, for future comparison. Before the arrival the 8th of march, thin films of silicate (olivine composition) were synthesized on 8 ZnSe windows. Two of them were used as reference or blanks and have not been used for the experiments.

The formation of the ice and its chemical evolution during and after irradiation have been monitored by IR spectroscopy. Table 1 presents the experiments performed and the fluence of the beam calculated for each experiment. The ions beam was iron (Fe) at 39.2 MeV/ions, the temperature of the sample order 15k, and the temperature ramp set at 3k/min from 15 to 100 K, 5K/min from 100 to 200 K, and 10K/min from 200 to 300K.
<table><thead><tr><td>Day</td><td>window</td><td>Composition (gaz phase)</td><td>Mbar pressure deposited</td><td>Final fluence (ions/cm²)</td></tr></thead><tbody><tr><td>20230408</td><td>W1 ZnSe</td><td>H₂O:CH₃OH (1:1)</td><td>1 mbar in 38 min</td><td>6.862x10¹²</td></tr><tr><td>20230408</td><td>W2 ZnSe + olivine1</td><td>H₂O:CH₃OH (1:1)</td><td>1 mbar in 19 min / ~0.8 µm</td><td>6.862x10¹²</td></tr><tr><td>20230408</td><td>W3 ZnSe + olivine2</td><td></td><td></td><td>6.862x10¹²</td></tr><tr><td>20230409</td><td>W1 ZnSe</td><td>H₂O:NH₃:CH₃OH (3:1:1)</td><td>5 mbar</td><td>1x10¹³</td></tr><tr><td>20230409</td><td>W2 ZnSe + olivine3</td><td>H₂O:NH₃:CH₃OH (3:1:1)</td><td>5 mbar</td><td>1x10¹³</td></tr><tr><td>20230409</td><td>W3 ZnSe + olivine4</td><td>H₂O:NH₃:CH₃OH (3:1:1)</td><td>~0.7 mbar / ~0.5 µm</td><td>6.862x10¹²</td></tr><tr><td>20230410</td><td>W1 ZnSe</td><td></td><td></td><td></td></tr><tr><td>20230410</td><td>W2 ZnSe + olivine8</td><td>H₂O:NH₃:CH₃OH (3:1:1)</td><td>&lt; 0.1 mbar</td><td>1x10¹³</td></tr><tr><td>20230410</td><td>W3 ZnSe + olivine7</td><td>H₂O:NH₃:CH₃OH (3:1:1)</td><td>2 mbar</td><td>1x10¹⁴</td></tr></tbody></table>

Different mixtures have been tested (table 1), but as a first series of experiments, we wished to investigate the role of the silicate on the formation of the organic residue and its composition. Hence, we made ices containing water, ammonia and methanol, all together irradiated by ions at low temperature.
# 7. Ion induced electron emission from radiosensitizing agents

Experiment number: P1302

Date: July 2023

## Spokesperson and co-authors

Violaine VIZCAINO (CIMAP)
Suvasis SWAIN (CIMAP)
Alain MERY (CIMAP)
Jean-Yves CHESNEL (CIMAP)

## Abstract

In ion beam therapy, radiosensitizers are used in order to enhance, locally, the ionizing radiation damage in biological matter. Much effort has still to be made to understand the basic mechanism and physical processes explaining this enhancement effect. One of the explanation is the important release of electrons from such agents. Therefore, we have measured ion-induced electron emission from two radiosensitizing agents molecules (Iodouracil and bromouracil) using a newly developed experimental set-up based on velocity map imaging (VMI) technique. This technique allows measuring, at once, all electrons emitted in a solid angle of 4π steradians with energy as low as a few tenths of eV up to 200eV. We provide absolute cross sections (total or as a function of energy and/or angle) and compare them to the one from uracil in order to determine the sensitizing factors.

## Experiment report

Ion collision with biologically relevant molecules has received increasing interest due to applications to radiation biology. Studies of the collision between multiply charged ions and molecules in the gas phase help understanding the fundamental mechanisms involved at the molecular level (fragmentation, electron emission). In the past years, absolute total or differential cross-sections for electron emission have been measured for nucleobases and amino acids. Experiments were mainly performed with bare ions such as proton, C6+ or O8+ with a kinetic energy of a few MeV.

Enhancement of ionizing radiation damage in biological matter due to the presence of radiosensitizer has been shown but much effort has still to be made to understand the basic mechanism and physical processes explaining this effect. With this experiment, we are helping to answer the question by measuring absolute electron emission cross section from halogenated nucleobases.

To do so, we have used new crossed beam experimental set-up dedicated to the measurement of absolute cross-sections for ion-induced electron emission from atoms, molecules and nanoparticles that has been recently built. With the previous allocated beamtime, we have validated our methodology by measuring the first absolute cross section from DNA/RNA bases (Uracil and Adenine) with this set-up on the IRRSUD beamline as well as SME beamline (P1230).

Absolute cross section are directly estimated from the number of emitted electrons Ne-, the number of projectile ion beam Np, the density ρ of the target beam (measured with a quartz crystal microbalance), the detector efficiency ε and the length l of the collision volume due to the beams overlap. Electrons are detected using a Velocity Map Imaging (VMI) spectrometer that allows collecting, at once, electrons with different kinetic energies emitted in a solid angle of 4π steradians without the need to rotate an energy analyser spectrometer. The image on the detector represent the 2D projection of the electron cloud produced by the ionization of the target and by applying an inverse Abel transform we can reconstruct the full momentum (energy and emission angle) of the emitted electrons in order to get the electron yield as a function of angle (θ), energy (E) or both. This method, using direct determination of absolute cross section rather than normalization to known scattering processes and VMI technique rather than standard electron spectrometer, is new but has been proven accurate.

We have measured the absolute cross sections for two 5-halouracil molecules. 5-halouracil molecules have the same structure than the RNA base uracil but one the H atoms is replaced by an halogen atom such as bromine (Br) or iodine (I) as seen in the figure below. These molecules are in powder form at room temperature and are put in the gas phase thanks to an oven that has two independent cavities: the effusion cell in which the powder of molecules is inserted, and the hot lip which allows shaping the beam thanks to an aperture tube (length = 30 mm,
diameter = 3 mm). The hot lip is held at higher temperature that the effusion cell to avoid condensation in the small exit aperture. The temperature are chosen to be below any thermal decomposition of the molecules.

Total σ, single (dσ/dE, dσ/dθ) and double differential (d²σ/dEdθ) cross sections have been determined and compared them to the Uracil in order to determine the sensitizing factors, i.e. the increase of the cross section due to the presence of the halogen atom.

In the Figure below, we show the single differential cross section (SDCS(E) or dσ/dE(E)) as a function of the emitted electron energy for both Uracil and Iodouracil. At low energy (around 1eV), the cross section is almost a factor 3 higher for iodouracil. This ratio decreases as the energy of the emitted electron increases but still it remains higher than 2 up to a few tenths of eV. Such massive increase in the cross section cannot be explained by the number of valence electrons in each molecules. Indeed, according to theoretical calculations taking into account 29 orbitals for Uracil and 55 for Iodouracil (A. Mandal et al. Phys Rev A 102, 062811 (2020)) an average enhancement of 1.15 is expected for the energy range of 1 to 30 eV. Our observation would rather indicate a collective excitation (atomic giant resonances) of 4d correlated electrons in I atom. Theoretical calculation need to be implemented to better quantify such collective processes and further experiments should be performed to confirm some observation for the angular dependence of the enhancement factor.

<figure><img src="image_171.png" /><figcaption>Absolute single differential cross section dσ/dE(E) in cm²/eV as a function of electron energy from Iodouracil and Uracil upon 0.98meV/u C4+ collision</figcaption></figure>
# 8. Heavy Ion Irradiation of Scaffolded DNA Nanostructures

Experiment number: 1344 P1327-H

## Spokesperson and co-authors

Jaroslav Kočíšek, Leo Sala, Agnes Zerolová
J. Heyrovský Institute of Physical Chemistry of the CAS, Dolejškova 3, Prague, 182 23, Czech Republic
Dominik Pinkas

Institute of Molecular Genetics of the CAS, Vídenská 1083, 142 20, Prague, Czech Republic
Violaine Vizcaino, Alain Mery, Alicja Domaracka, Hermann Rothard, Philippe Boduch

Normandie Univ, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, Boulevard Henri Becquerel, BP 5133, 14070, Caen
cedex 5, France

## Abstract

In a series of experiments, we explored the structural damage induced by heavy ions to DNA origami nanostructures deposited on silicon surfaces. These pilot experiments provide a base for further exploration of unique combinations of top-down ion beam processing techniques with bottom-up self-assembly in nano-tech applications. The experiments also provide a valuable set of data for our ongoing research towards elucidating the details of the multiscale processes during radiation interaction with living tissue.

<figure><img src="image_172.png" /></figure>

## Experiment

DNA origami are nanostructures made by folding DNA into precisely defined shapes. The starting material is a long single strand consisting of several thousands of interconnected DNA bases that can be produced naturally. This scaffold strand is complemented by a set of designed staples. Under precisely defined conditions, the staples self-assemble with scaffold DNA to form double helix DNA folded into a desired shape.¹ Since the position of every single molecule in the final structure is well known from the design step, the specific DNA sequences can be used to bind other components to DNA origami at precise locations at their surface. This makes DNA origami superior to any other type of nanoparticle. Additionally, the nanoparticles possess several more advantages arising from DNA as a material that can be useful for a variety of applications.²

In our group, we are using the nanostructures to study fundamentals of radiation interaction with DNA. In these experiments, we can use the DNA origami as a platform for the precise positioning of molecules for single-molecule studies³ or we can use the DNA origami as a tiny dosimeter to explore the radiation effects on the structure⁴. The ultimate goal of our current efforts is to provide experimental verification for multiscale processes in radiation interaction with materials, such as shock waves.⁵ While the DNA origami sensitivity to damage via radicals or low-energy electrons seems to be low, its susceptibility to mechanical stress is high, and therefore, we believe origami is the ideal probe for this process. However, the shock-wave hypothesis represents a significant paradigm shift,
and therefore experiments for its proof must be performed with special carte. The current experiments at GANIL allowed us to test several interaction regimes and provide a ... valuable base for further experiments in this direction, however the full test of the hypothesis will require much more experiments. However, the performed experiments are not interesting only for the fundamental radiation chemistry and physics. The range of projectiles and conditions, which we were able to explore during two planned experiments, allowed us to disentangle structural damages to the DNA origami deposited on surfaces, that could be interesting for nanotechnology.

Thanks to a spread of the software to design DNA origami and commercial availability of synthetic DNA strands, the DNA origami technique has become very popular in many fields including in nanotechnology. Examples include the use of these structures as a precisely shaped form for creating organometallic conducting nanostructures or their application in lithography.⁶ We have shown already that the nanostructures are very stable with respect to ionizing radiation damage, however at high doses the shape of the origami can be distorted.⁴ The current experiments with DNA origami deposited on silicon surface, performed at laboratory conditions at IRABAT platform with Fe²⁵⁺ ions at 60 MeV/u and under vacuum at IRRSUD platform with Fe¹⁰⁺ ions at 0.7 MeV/u enabled us to answer if the structures remain stable in typical material processing techniques such as ion implantation, ion beam deposition, or milling.

Results of these experiments were, already published in the journal BJNANO⁷ and therefore we will describe them only briefly. The main observation is that the nanostructure-to-surface interaction is strong allowing for high doses of radiation or cutting the nanostructure by ion beam without significant changes in the shape of the nanostructures. Typically, only a region of approximately 10nm around the ionization track was influenced, also limited by the resolution of the used AFM (atomic force microscopy) for the analysis. In some cases, profile heights change which means some components of the origami could be evaporated from the structure and probably the heavy atoms such as phosphorus remain on the substrate. Such change can be used to deposit the metal structures on the surface of a well-controlled shape of DNA origami. The observations opens the doors for novel applications, where DNA origami nanostructures could be used as an active component in lithographic techniques and as a part of nanoelectronics.

<footnote>(1) Rothemund, P. W. K. Folding DNA to Create Nanoscale Shapes and Patterns. *Nature* **2006**, *440* (7082), 297–302.
https://doi.org/10.1038/nature04586.</footnote>

<footnote>(2) Wang, P.; Meyer, T. A.; Pan, V.; Dutta, P. K.; Ke, Y. The Beauty and Utility of DNA Origami. *Chem* **2017**, *2* (3), 359–382.
https://doi.org/10.1016/j.chempr.2017.02.009.</footnote>

<footnote>(3) Sala, L.; Lyshchuk, H.; Šáchová, J.; Chvátil, D.; Kočiček, J. Different Mechanisms of DNA Radiosensitization by 8-Bromoadenosine and 2'-Deoxy-2'-Fluorocytidine Observed on DNA Origami Nanoframe Supports. *J. Phys. Chem. Lett.* **2022**, *13* (17), 3922–3928.
https://doi.org/10.1021/acs.jpclett.2c00584.</footnote>

<footnote>(4) Sala, L.; Zerolová, A.; Rodriguez, A.; Reimitz, D.; Davídková, M.; Ebel, K.; Bald, I.; Kočiček, J. Folding DNA into Origami Nanostructures Enhances Resistance to Ionizing Radiation. *Nanoscale* **2021**, *13* (25), 11197–11203.
https://doi.org/10.1039/D1NR02013G.</footnote>

<footnote>(5) Solov'yov, A. V.; Verkhovtsev, A. V.; Mason, N. J.; Amos, R. A.; Bald, I.; Baldacchino, G.; Dromey, B.; Falk, M.; Fedor, J.; Gerhards, L.; Hausmann, M.; Hildenbrand, G.; Hrabovsky, M.; Kadlec, S.; Kočiček, J.; Lépine, F.; Ming, S.; Nisbet, A.; Ricketts, K.; Sala, L.; Schlathölter, T.; Wheatley, A. E. H.; Solov'yov, I. A. Condensed Matter Systems Exposed to Radiation: Multiscale Theory, Simulations, and Experiment. *Chem. Rev.* **2024**. https://doi.org/10.1021/acs.chemrev.3c00902.</footnote>

<footnote>(6) Heuer-Jungemann, A.; Linko, V. Engineering Inorganic Materials with DNA Nanostructures. *ACS Cent. Sci.* **2021**, *7* (12), 1969–1979.
https://doi.org/10.1021/acscentsci.1c01272.</footnote>

<footnote>(7) Sala, L.; Zerolová, A.; Vizcaino, V.; Mery, A.; Domaracka, A.; Rothard, H.; Boduch, P.; Pinkas, D.; Kocišek, J. Ion Beam Processing of DNA Origami Nanostructures. *Beilstein J. Nanotechnol.* **2024**, *15* (1), 207–214.
https://doi.org/10.3762/bjnano.15.20.</footnote>
VII. ARIBE

<figure><img src="image_173.png" /></figure>
# 1. Low energy ion detection system for the FISIC project

Experiment number: P1328

Date: June 19-30, 2023

## Spokesperson and co-authors

M JOLLY, Emily Lamour, Christophe Prigent, Martino Trassinelli, Stéphane Macé, Sebastien Steydli, Dominique Vernhet (INSP, Sorbonne Universite, CNRS UMR 7588, Paris), Alain Méry, Jimmy Rangama, Patrick Rousseau, Jean-Marc Ramillon, Jean-Yves Chesnel (CIMAP, CEA/CNRS/ENSICAEN, Université de Caen Normandie, Caen)

## Abstract

In this experiment, we characterized the modified version of the low-energy detection system of the FISIC project. This system consists of a 90° electrostatic ion charge state analyzer, constructed with two deviation plates enclosed by Matsuda plates. The analyzer is connected to a custom-built detection device that combines a Faraday cup and a position-sensitive detector. Experiments conducted in November 2021 at ARIBE revealed a significant contribution of background ions due to scattering on the electrode walls or ionization of the residual gas. Consequently, several modifications were made to the analyzer geometry to reduce these contributions to acceptable levels. In June 2023 the updated setup was connected to an OMEGA-shaped beam purifier, that had been previously characterized at ARIBE in 2018. Estimates of well-known capture cross-sections as well as less established ionization cross-sections in the literature at these collision energies were obtained. Some of the background contributions seen in 2021 were successfully reduced with the modified setup. However, the noise level, although better controlled, remains too high for future experiments at higher energies. Therefore, we must consider modifying the detection system by decoupling the Faraday Cup (FC) from the Microchannel Plates (MCPs).

## Experiment report

The requested beam time was part of the preparatory phase for the FISIC (Fast Ion Slow Ion Collisions) project. The primary goal of this project is to establish a unique crossed beam ion-ion experiment to measure absolute cross-sections of electronic processes in the velocity range where ion stopping power is at its maximum. The initial phase involves conducting experiments on ion-atom and ion-ion collisions at low velocities in the INSP lab in Paris, utilizing the SIMPA and FISIC ion sources. The collision zone of the FISIC project comprises three parts (see Figure 1). Upstream of the collision chamber, the ion beam undergoes "cleaning" to ensure that the ions with the desired charge state enter the collision chamber. This is necessary because the incoming ion beam may contain a small fraction of undesired charge states formed in collisions with residual gas along the beamline. To address this, a dedicated electrostatic purification system, known as "Omega," was designed and successfully tested at ARIBE [1]. Downstream of the collision chamber, the low-energy ion products are q-analyzed and collectively detected. The initial version of this analyzer was tested in November 2021 at ARIBE, and the results led to design modifications that were further tested during the 2023 beam time [2].

The charge state analyzer consists of a cylindrical 90° electrostatic analyzer coupled with a detection system developed in collaboration between CIMAP and INSP. A portion of the upper plate of the analyzer is drilled to install a transparent grid, allowing ions that could otherwise contribute to background noise to escape. This experiment aimed to test the new version of the ion spectrometer and to evaluate the effect of the charge state purifier. The spectrometer was directly connected to the Omega purifier, and both were linked to the ARIBE L4 beamline (see Figure 2). The experiment utilized 10 qkeV beams of O³⁺, Ar⁹⁺, and Ar¹²⁺ with currents ranging from a few picoamperes (pA) to a few tens of nanoamperes (nA) at the level of the detection system. Two detector positions were employed: one to measure secondary beams produced by capture on the residual gas and another for secondary beams produced by ionization (Figure 3 and see also Figure 4 for SIMION simulations). Multiple runs were conducted with systematic variations in parameters such as the omega ON or OFF, voltage changes on inner and outer omega plates, deflectors, Matsuda plates, and detector voltages. For an Ar¹²⁺ primary beam, the new design of the ion spectrometer successfully eliminated the parasitic peak observed in 2021 (see Figure 5). In all capture configuration runs, the omega's effect was consistent with predictions, significantly reducing secondary beams. Runs with Ar⁹⁺ and Ar¹²⁺ as primary beams allowed the estimation of three capture cross-sections, which were found to be in good agreement with Müller-Salzborn cross-sections [3].
<table><thead><tr><td>Process</td><td>Estimations from measurements</td><td>Müller-Salzborn cross sections</td></tr></thead><tbody><tr><td>Ar<sup>12+</sup> → Ar<sup>11+</sup></td><td>( 1.4 ± 0.7 ) x 10<sup>-14</sup> cm<sup>2</sup></td><td>1.3 x 10<sup>-14</sup> cm<sup>2</sup></td></tr><tr><td>Ar<sup>12+</sup> → Ar<sup>10+</sup></td><td>( 2 ± 1 ) x 10<sup>-15</sup> cm<sup>2</sup></td><td>2.9 x 10<sup>-15</sup> cm<sup>2</sup></td></tr><tr><td>Ar<sup>9+</sup> → Ar<sup>8+</sup></td><td>( 8 ± 6 ) x 10<sup>-15</sup> cm<sup>2</sup></td><td>9.5 x 10<sup>-15</sup> cm<sup>2</sup></td></tr></tbody></table>

In the ionization configuration, the O³⁺ runs revealed a distinct semi-circular background, which was replicated using SIMION simulation software and attributed to elastic collisions within the analyzer (Figure 6). Additionally, ions resulting from the ionization of Ar⁹⁺ were detected (Figure 4), and the estimated cross-section for Ar⁹⁺ → Ar¹⁰⁺ was found to be (3 ± 2) x 10⁻¹⁷ cm². This value, while larger by several orders of magnitude than expected, was consistent with values reported in the literature [4].

Overall we found that the transmission of the beam through the whole system (omega + ion spectrometer +detector) is 100%, and the ion spectrometer has the expected charge state separation power. The omega is effectively fulfilling its function by reducing the intensity of secondary beams by a factor of 10. However, despite reducing and eliminating some background contributions, the expected performance for ion detection was not fully achieved. High background noise from beams with currents up to the microampere (μA) range prevented the use of higher current ion beams. Further modifications to the spectrometer to eliminate background from elastic collisions may be necessary, along with a redesign of the detector. A proposed solution involves spatially separating the detection of the primary beam using a Faraday Cup and the secondary beams using MCPs, to prevent secondary electrons emitted from the Faraday Cup from reaching the MCPs. This experiment provided valuable insights into the setup and its performance, and the results will be crucial in guiding future design changes for the spectrometry and detection system.

[1] Schury, D et al, RSI 90 083306 (2019)

[2] Jolly, M et al, Atoms, 10, 146 (2022)

[3] Müller, A and Salzborn, E, Phys. Lett.A, 62, 6 (1977)

[4] A Diehl et al 2001 J. Phys. B: At. Mol. Opt. Phys. 34 4073
<figure><img src="image_174.png" /><figcaption>Figure 1: Overview of the FISIC collision zone with the Omega charge state purificator, the Collision chamber and the ion spectrometer.</figcaption></figure>

<figure><img src="image_175.png" /><figcaption>Figure 2: Trajectories of the primary and secondary beams from capture in the spectrometer and the OMEGA when it is turned on (a) and off (b)</figcaption></figure>

<figure><img src="image_176.png" /><figcaption>Figure 3: Trajectories of the secondary beams originating from capture and ionization in the ion spectrometer and the ion detector</figcaption></figure>
<figure><img src="image_177.png" /></figure>

Figure 4: SIMION simulations of trajectories of the primary and secondary beams (produced by capture and ionization) in the spectrometer with the detector position to measure secondary beams only produced by ionisation for an Ar<sup>9+</sup>(a) and O<sup>3+</sup>(b) primary beam

<figure><img src="image_178.png" /></figure>

Figure 5: Comparison showing the effect of the spectrometer modifications on the parasitic peak background

<figure><img src="image_179.png" /></figure>

Figure 6: Simulated trajectories of capture beams from an O³⁺ primary beam in ionization configuration, showing the trajectories of the elastic collisions beams
## 2. Ion collision induced excitation dynamics in PAHs

Experiment number: P1342-A

Date: June 11-17, 2023

### Spokesperson and co-authors

Najeeb Punnakayathil (NASA Ames Research Center, CA, USA)

Andrew L Mattioda (NASA Ames Research Center, CA, USA)

Patrick Rousseau (Université de Caen Normandie - CIMAP, GANIL, France)

Alicja Domaracka (Université de Caen Normandie - CIMAP, GANIL, France)

### Abstract

Low energy radiation interaction with polycyclic aromatic hydrocarbons (PAHs) causes local electronic energy loss and thus excitation of electrons, one such prominent mode of collective excitation in PAHs are known as plasmon excitation. Previous studies of photo-ion yield measurements performed over a large range of PAH has clearly shown plasmon excitation at 17 eV, but the ion collision-induced excitation process in PAHs is less studied. Unlike in the photoexcitation which are governed by selection rule, it is not possible to assess how strong the ion induced excitation in these molecules considering the complexity of interaction dynamics and consequences. The collective excitation states due to inner valence shell electrons are expected to couple with intramolecular vibrational distributions via single-particle states. Such coupling is strongly dependent on the symmetry, size, and aromaticity of the molecule. We have investigated the ion-induced coupling mechanism in the electronic states of PAHs molecules particularly tetracene ($C_{18}H_{12}$), its isomers chrysene ($C_{18}H_{12}$) and triphenylene ($C_{18}H_{12}$) in collision with low energy $He^{2+}$ and $Xe^{20+}$ ions in the energy range of 5 - 20 qkeV

### Experiment report

We studied the ion-PAH interaction by using the time-of-flight mass spectrometer set-up (COLIMACON) at ARIBE facility, GANIL. We use the multihit data acquisition system to measure the multi-ionization and multi fragmentation/dissociation of the PAH molecules, Tetracene ($C_{18}H_{12}$) - carcinogenic PAH and its isomers Chrysene and Triphenylene. As for the range of energies of projectiles, the low energy ions where electronic stopping dominant and low charge state, $He^{2+}$ and high charge state $Xe^{20+}$ at 5 and 20 qkeV were used. The excitation/ionisation/fragmentation mechanisms of PAHs in this energy range of radiation are also important as the supernova explosion will release radiation this range will interact with PAHs in the colder region in ISM. This energy range covers different excitations in PAHs, including the outermost $\pi-\pi^*$ excitations at~7 - 8 eV as well as $\sigma-\sigma^*$, $\sigma-\pi^*$ and $\sigma - \sigma^*$ excitations, which peak at ~17 eV. The projectile ion beams ($He^{2+}$, $Xe^{20+}$) were produced in the ECR source and accelerated to the interaction region of a Wiley-McLaren time-of-flight (TOF) mass spectrometer. The neutral target molecules are produced by heating the PAH powders in a resistively heated oven (tetracene (125°C), chrysene (95°C) and triphenylene (70°C) and the isolated gas phase molecules are introduced in the interaction region through a nozzle, where the sample undergo collisions with the projectile. The experiment was performed on two energies (5, 20 qkeV) of projectile with ion beam flux of about 1 particle nano amperes. In total, to perform experiment with three isomers with He and Xe ion beams at two different energies, the experiment took 6 days of beam time (2 days for Xe ion beams and 4 days of He ion beams). In addition, we took need 2 days between two ion beams for change of the target molecule.

The experiment were successful and we are currently working on the data analysis, we found some interesting correlation in the decay dynamics and molecular structural fragmentation and isomerisation in case of ion-PAH collision mechanism. Once the results are concluded we will publish in the peer reviewed journals. By realizing the complexity of interaction dynamics, along with the experimental studies, we are also working on Monte Carlo simulation for the ion-molecule collision which provides projectile energy loss and relative fragmentation cross-section for molecular targets.

Report to beam time of 90keV O$^{6+}$ on organic molecules: benzonitrile and mixtures of acetonitrile and benzene.

Wania Wolff, Physics Institute of the Federal University of Rio de Janeiro
### 3. Radiate project: 23003101-ST

**June 2023**

In this work, reflection-absorption IR spectra were collected in the 5000-600 cm⁻¹ range for acetonitrile, benzene, benzonitrile and the mixtures of acetonitrile and benzene.

For the sake of comparison first measurements of the infrared spectrum benzonitrile were performed to compare it with the database supplied by Wiley. The benzonitrile sample was purchased from Sigma Aldrich with a purity of (99.9%), HPLC, with water content of 0.03%. The appropriate sample we find out should be benzonitrile 99% anhydrous with water content of 0.003%, ten times less than the HPLC sample. The freeze-pump-thaw method was applied on the liquid sample to degas solvents and water. Thick and thin samples were deposited varying the delta ramp pressure for approximately 5 and 9 minutes onto a ZnSe subtract. The temperature of deposition was 10K. Unfortunately, the IR spectrum showed very clearly the IR band of water superimposed to the benzonitrile bands and it is difficult to analyze the data considering the spectra shown from the database (see Figure 1).

<figure><img src="image_180.png" /><figcaption>Figure 1 IR spectra of water and benzonitrile extracted from Wiley database.</figcaption></figure>
<figure><img src="image_181.png" /><figcaption>Figure 2 IR spectra of acetonitrile, benzene and benzonitrile extracted from Wiley data base.</figcaption></figure>

Figure 2 shows the IR spectra of acetonitrile, benzene and benzonitrile extracted from Wiley data base.

It is essential to reduce the water contribution to the spectra for all compounds. The ramp line was heated before new injection, but it turned out that most of the water contents derived from the sample itself. The benzonitrile liquid was treated for almost 24h in molecular sieves 4A to adsorb the water molecules, but the procedure did not reduce the water presence significantly as verified in the next IR spectra. It was imperative to collect the IR spectra of pure condensed benzonitrile. The only efficient method to suppress the water presence would have been distillation, but the time and means did not allow this option (proposal of distillation of the sample was not included in the project). Afterwards in a chemistry laboratory of the Federal University of Rio de Janeiro the distillation procedure was done, and it turned out to be very efficient, eliminating most of the water contents. At home time of flight mass spectra were collected under impact of 2.3 keV electrons before and after distillation to probe the effectiveness of the process. The thick and thin samples were exposed to O6+ at currents of µA with fluences starting at 2e13 ions/cm2 and reaching a total accumulated fluence of 1e15 ions/cm2. The damage induced in the films are presented in figure 3.
<figure><img src="image_182.png" /><figcaption>Figure 3 show representative the damage induced in the thick and thin samples of benzonitrile.</figcaption></figure>

Following the proposal, a mixture of acetonitrile and benzene was prepared. For comparison prior to the mixture experiment acetonitrile and benzene pure samples were exposed to the oxygen beam and IR spectra collected. The molar fraction of the compound's acetonitrile and benzene in the mixture was fixed to 1:4. The molar fraction that showed the possible formation of benzonitrile was previously established in the chemistry laboratory of the Federal University of Rio de Janeiro. The injection was monitored by a quadrupole mass spectrometer, which did not show the expected ratio, but measured equal amounts of the compounds. The mixture did not show any trace of benzonitrile IR bands. It was difficult to compare the mixture IR spectra to the benzonitrile spectra. New samples of the mixture heated to 110K followed by a cooling down to 10 K to increase the interaction of the compounds were also tried. Under electron impact the experience showed that after heating the films slightly below its sublimation more aggregates are formed. All measurements were negative with respect to the aggregate's formation in the mixture. The negative results are partly explained by the stopping powers for ninety keV oxygen ions of the acetonitrile, benzene and benzonitrile. The nuclear stopping power for 90keV O6+ are than the electronic one. Previous experiments with pyridine had already shown that daughter products are not formed for ions at this energy range. Water molecules trap acetonitrile molecules or segregate distinct species in mixtures by weakening the interaction between the molecules [Souda, 2016]. In the case of the benzonitrile formation in ice c-C6H6:CH3CN mixture the presence of water inhibits its formation [Maksyutenko et al. 2022]. Therefore, particular care needs to be taken to avoid water contamination in the anhydrous samples and the deposition should be free of water.

At present calculations were performed to get the structures of benzonitrile cations and possible aggregates and next the IR spectrum of neutral and cationic benzonitrile in crystalline phase will be obtained.

## Conclusion and perspectives

These preliminary data with low energy (around hundred keV) charged oxygen ions delivered at ARIBE (Ganil-Caen) beamline impinging anhydrous acetonitrile and benzene ice mixtures resulted negative with respect to the benzonitrile formation mostly suggested as due to low production of secondary electrons and subsequent radicals in the sample. On the other hand, very recent experiments on c-C6H6:CH3CN binary ice mixtures upon the incidence of two keV electrons and Lyman alpha photons suggest its formation [Maksyutenko et al. 2022]. Very tiny structures, at 2230 cm-1 and 1495 cm-1 were assigned to benzonitrile produced in the acetonitrile-benzene mixture as shown in figure 4. The bands indicated in black solid line were assigned to pure benzonitrile.
<figure><img src="image_183.png" /><figcaption>Figure 4 Data extracted from Maksyutenko 2022</figcaption></figure>

As the ice processing is dependent on collision parameters, as charge, mass and energy of heavy ions, electronic stopping power of the projectiles, ionization, and dissociative cross sections, absorbed energy acquired by the reactants, and penetration depth in the ice sample we have proposed the impact of swift heavy ions. High velocity projectiles in the electronic stopping regime with masses ranging from Carbon-Ne, or Ar-Kr, (Iron, Niquel) or Xe with energies from 0.3 up to 1 MeV/u. These ions can reach a penetration depth around 10-20 microns depositing almost constant amounts of energy along the track since the thickness of the sample, d, is smaller than the penetration (around 10 times the d) so that the full length of the ice sample is processed inducing the production of much more radicals due to the enhanced secondary ionization by high energy delta electrons, along the track within a track radius much larger than for the slower projectiles delivered by ARIBE beamline. The measurements of the IR bands intensity through Fourier transform spectroscopy with the IGLIAS setup as function of the projectile fluence would allow to follow the physical and chemical radiolytic modifications of the pure and mixed samples and estimate the apparent destruction cross section, the radiation resistance, determine the survival time of the molecule and suggest the appearance of new and expected absorption features. Irradiation times of 4-5 hours need to be set for the mixtures with varying composition ratios of benzene and acetonitrile to allow the expected new bands corresponding to new daughter species to emerge with intensity as product of the interaction between benzene and acetonitrile, like the bands of benzonitrile and biphenyl, respectively [Lemmens et al. 2022]. The setup to be used is IGLIAS from CIMAP and beam line at IRRSUD. They both are best adequate for the project. References with impact in astrochemistry suggest the relevance of the investigation.

Reggie L. Hudson, Yukiko Y. Yarnall, 2022 Icarus 377, 114899.

Radha Gobinda Bhuin, Rabin Rajan J. Methikkalam, Bhalamurugan Sivaraman, and Thalappil Pradeep 2015 The Journal of Physical Chemistry C, 119, 11524.

Ada Bian, Prudence C.J. and Agnihotri, Aditya N. and Boduch, Philippe and Domaracka, Alicja and Kanuchova, Zuzana and Rothard Hermann, 2021 European Physical Journal D 75, 57.

J. Cui, R.V. Yelle, V. Vuitton, J.H. Waite Jr., W.T. Kasprzak, D.A. Gell, H.B., Niemann,

Maksyutenko, Pavlo, Rafael Martín-Doménech, Elettra L. Piacentino, Karin I. Öberg and Mahesh Rajappan. 2022 The Astrophysical Journal 940, 113.

Alexander K Lemmens, Daniël B Rap, Sandra Brünken, Wybren Jan Buma, Anouk M Rijs, Van't Hoff Phys. 2022 Physical Chemistry Chemical Physics, 24, 14816.

B. Augé, T. Been; P. Boduch; M. Chabot; E. Dartois; T. Madi; J. M. Ramillon; F. Ropars; H. Rothard; P. Voivenel, 2018 Review Scientific Instruments. 89, 075105.

R. Souda, 2016, JPC C120, 934
# 4. Radiolysis of Complex Organic Molecules (COMs) in the condensed Phase

Experiment number: 19001773-ST

Date: June 6, 2023

## Spokesperson and co-authors (affiliation)

Z. Kanuchova, Astronomical Institute of SAS, 05960 T. Lomnica, Slovakia

P. Boduch, A. Domaracka, H. Rothard, C. A. P. da Costa, CIMAP-CIRIL-Ganil, Normandie Univ, ENSICAEN, UNICAEN, CEA, CNRS, Caen, France

## Abstract

Ices are omnipresent in cold regions in space. Examples include comets, dust grains, trans-Neptunian objects, surfaces of planets and their satellites. Although such ices are mainly formed from small molecules with two to five atoms (e.g., water, carbon oxides, nitrogen, methane), larger, complex organic molecules (COMs) may be present. Ionizing radiation (UV photons, electrons, ions from cosmic rays or solar wind) induces several physico-chemical processes such as radiolysis and subsequent formation of new molecules including COMs. The radioresistance of pyridine ice was probed under MeV ion beams irradiation by investigating the dependence of radiolysis and structural modifications as a function of projectile stopping power.

## Experiment report

Pyridine (C₅H₅N) is an important complex organic molecule (COM). It has a similar structure as benzene, but with a nitrogen atom (N) replacing a methine bridge (=CH-), giving the ring the heterocyclic feature. It is proposed that pyridine also represents the key building block of nitrogen-substituted polycyclic aromatic hydrocarbons.

The radioresistance of pyridine ice was probed under MeV ion beams irradiation by investigating the dependence of radiolysis and structural modifications as a function of projectile stopping power. In recent years, amorphous and crystalline pyridine films (Fig. 1) were irradiated at different beam lines of the Grand Accelerateur d'Ions Lourds (GANIL). Different projectiles were used: i) 396 MeV Ar¹⁷⁺ and 626 MeV Ni²⁶⁺ at SME, ii) 61.3 MeV Kr¹⁵⁺ at IRRSUD. The latest experiments of the series were conducted in 2023, using 30 keV He²⁺ ions of the ARIBE beam line of the GANIL for energetic processing of pyridine. Experiments were performed using the high vacuum setup IGLIAS (Auge et al., 2018) mounted as the end station of the ARIBE beam line.

The evolution of column densities as a function of beam fluence (i.e. the accumulated number of projectiles per surface area irradiating the sample) was followed by Fourier Transform Infrared spectroscopy (FTIR) in transmission mode.

<figure><img src="image_184.png" /></figure>

Figure 1: Crystalline (top red curve) and amorphous (bottom black curve) pyridine infrared spectra at 15 K. Inserted graph highlights differences between amorphous and crystalline bands in the region of 1550 to 1400 cm⁻¹. Offsetting of the red curve for better visualization. Pyridine vibration modes are highlighted: 1031 cm⁻¹ (v12 C5H5N trigonal ring breathing), 1068 cm⁻¹ (v18a C5H5N C-H deform), 1438 cm⁻¹ (v19b C5H5N ring stretch), and 1483 cm⁻¹ (v19b C5H5N ring stretch).
Based on previous experiments we can say, that energetic processing of crystalline pyridine with heavy MeV ions induce its amorphization. In contrast to these findings, the complete amorphization of crystalline pyridine was not achieved by irradiation 30 keV He⁺ ions (Fig. 2). However, amorphization was expected at the achieved fluences, and further experiments are needed to elucidate this ambiguity.

<figure><img src="image_185.png" /><figcaption>Figure 77 Evolution of infrared spectra of crystalline pyridine at 15 K with fluence of various energetic ions.</figcaption></figure>

Results of the latest irradiation experiments of crystalline and amorphous pyridine with 30 keV He⁺ ions, as well as MeV heavy ions, are currently under detailed analysis and are being prepared for a publication in a peer-reviewed scientific journal.
# 5. Investigation of ion-induced fragmentation of diatomic molecules as a function of projectile charge

Experiment number: P1179A

Date: May 21 – June 3, 2023

## Spokesperson and co-authors

Zoltán Juhász, Béla Sulik, Péter Herczku
(HUN-REN Institute for Nuclear Research, Hungary, 4026 Debrecen, Bem square 18/c)

Jean-Yves Chesnel, Violaine Vizcaïno, Jimmy Rangama, Alain Méry, Suvasis Swain
(CNRS CIMAP, Caen, France)

Sándor Demes
(Institute of Physics of Rennes (IPR), University of Rennes, 263 avenue du Général Leclerc
35042 Rennes CEDEX, France ; HUN-REN Institute for Nuclear Research)

## Abstract

We have studied the fragmentation of O₂ and N₂ by multiply charged ions of the same atomic species, which are relevant for atmospheric sciences. The aim was to obtain results beyond the ones presently available for singly charged projectiles by measuring with projectiles of higher charge states. The results may find an application e.g., in the modelling of chemical processes in the atmospheres of Jupiter's moons, since highly charged ions continuously bombard these celestial objects. The planned program was to study collisions of O+, O²+, O³+ and O⁴+ projectiles collisions with O₂ molecules, as well as the similar collision systems by replacing O (oxygen) by N (nitrogen) in both collision partners.

## Experiment report

Energy/charge spectra of the fragment ions for the different collision systems were recorded by means of an electrostatic ion spectrometer available at ARIBE facility. We started the experiment with 20 keV O²⁺ + O₂ collisions. This spectrometer provides reliable data for fragments of kinetic energy larger than 1 eV. Below 1 eV, the trajectories of the fragments may be affected by spurious fields induced by surface charges and/or contact potentials. Therefore, the same collisions were investigated in ATOMKI with a field free time of flight (TOF) setup, which is ideal for investigation of the low energy fragments (< 1 eV). The two datasets are complementary and give full picture of the fragment emission. In the overlapping region the results agree well (see Figure 1.)

<figure><img src="image_186.png" /><figcaption>Figure 1</figcaption></figure>
The fragment energy spectra were dominated by low energy O+ ions, for which characteristic peaks appeared at 2.2, 3.3, 6.6, and 9.0 eV. These peaks were found to be isotropic. To identify the various charge-states of the ionic species contributing to each peak, we measured the time of flight of these different species within the spectrometer (see Fig. 2). To do so, it was necessary to pulse the beam. Besides the dominating O+ fragments, some O<sup>2+</sup> and O<sup>3+</sup> were detected (with decreasing amount with increasing charge state). Surprisingly, the molecular ion O<sub>2</sub><sup>+</sup> was also detected. Even more surprising is the fact that the molecular ion could be identified at relatively large emission energies, up to 20 eV, too. The question arises as to how an intact molecular ion can get such a large momentum transfer without breaking. This question needs to be answered by model calculations including the molecular nature of the target by *ab initio* or at least semi-classical level. At forward angles, high energy peaks of several keV due to recoiled fragment ions from binary collisions were also detected. These peaks show a steep angular dependence and O<sup>+</sup>, O<sup>2+</sup>, O<sup>3+</sup> contributions were all detected.

<figure><img src="image_187.png" /><figcaption>Figure 2</figcaption></figure>

Anion contributions where checked also but we did not find significant contribution for this collision system. Then we changed the projectile energy to 30 keV so as to check the projectile-energy dependence of the fragmentation process. Moreover, at 30 keV all the other projectile charge states up to 4 could be delivered by the ECR ion source, which allowed us to study the effect of charge state purely, without changing other parameters. No significant energy dependence was found, but the effect of the charge state is dramatic (see Fig. 3). At higher projectile charge states, the fragment emission concentrated at higher energies and the contribution of multiply charged fragments becomes significant. One may expect that the total fragmentation cross section integrated in the energy scale significantly increases with the charge state since higher charge state projectile can remove electrons from the target more efficiently and from larger internuclear distance by electron capture processes. We have found that the total cross section for triply charged projectile is about one order of magnitude higher than for doubly charged projectile. However, the difference between quadruply and triply charged projectile is less than a factor of two.
<figure><img src="image_188.png" /><figcaption>Figure 3</figcaption></figure>

For the binary peaks, systematic changes are observed: the O+ contribution decrease with increasing projectile charge state, the O²⁺ does not change significantly, while the O³⁺ contribution increases with the projectile charge state. After the experiments in Ganil, in a recent campaign we have measured some of the same collision systems (30 keV O³⁺ + O₂, 7.8 keV O⁺ + O₂) by means of the field free TOF setup, in order to extend the measured fragment energy range energy below 1 eV. These result are partially evaluated so far (see Fig. 4). Above 2 eV the two results are similar (note that the results are not absolutely calibrated yet). Below 2 eV, the TOF results show significantly larger cross section. This is the range, where the spectrometer transmission usually declines due to surface charges. This range is quite important, however, which is indicated by the high cross section values measured by means of the field free TOF apparatus in the range below the lower limit of the spectrometer. Above 400 eV, the spectra reported in Fig. 4 do not match to each other. This is due to the fact that the field-free TOF setup is limited in TOF resolution, thus making it less reliable for high emission energies. In contract, the electrostatic spectrometer available in Caen is an ideal system for detection of high-energy fragments. Therefore, the two setups are complementary.

<figure><img src="image_189.png" /><figcaption>Figure 4</figcaption></figure>

During this beamtime, very small time remained for measuring the collision systems of nitrogen ion projectiles colliding on N₂ molecules. However, we had already had some results from a previous beamtime. In this project we just made some supplementary measurements for the missing results from previous measurement, particularly
but not exclusively the binary peaks were measured for 5 keV $N^+ + N_2$ collisions (see Fig. 5). For this collision system, we also pulsed the beam in order to be able to measure the TOF of the various fragments through the spectrometer. We have observed a significant contribution of molecular ions emitted at low energies as one can accept for the strongly bonded nitrogen molecule. We would like to complete the nitrogen results during another beamtime at ARIBE with the electrostatic spectrometer, as well as at ATOMKI with the field-free TOF setup, so that the differences compared to the oxygen results could be studied in detail.

<figure><img src="image_190.png" /><figcaption>Figure 5</figcaption></figure>

### Legend

Figs 1 to 5: Doubly differential cross sections for fragment emission at the indicated emission angle $\theta$ (with respect to the beam direction) and as a function of the emission kinetic energy per charge unit for different collision systems indicated in the figures.

We note that the singly charged projectiles (Figs. 4-5) do not lead to characteristic peak structures in the fragment energy distribution between 1 and 10 eV like in the case of multiply charged projectiles (Fig. 3). This is triggering theoretically investigation. We also note that for the triply charged projectiles the structure is less prominent than for doubly and quadruply charged projectiles.

From the oxygen results we have a complete set of data that we would like to publish in Phy. Rev. A. The results may have some astrophysical implications on the exospheres of icy moons of Jupiter and Saturn. We plan to study these by model calculations, which may also be published in a thematic journal in astrophysics.

### Acknowledgments

The authors are grateful to Claire Feierstein-Plancq and Dr. Patrick Rousseau for beam tuning and technical assistance at the ECR ion source.
<figure><img src="image_191.png" /></figure>

05 ANNEXES
<figure><img src="image_192.png" /></figure>
I. PUBLICATION LIST

1. ARTICLES & PROCEEDINGS

[1] Zanon, E. Cle'ment, A. Goasduff, J. Mene'ndez, T. Miyagi, M. Assie', M. Ciemała, F. Flavigny, A. Lemasson and A. Matta, et al. "High-Precision Spectroscopy of $^{20}$O Benchmarking Ab Initio Calculations in Light Nuclei," Phys. Rev. Lett. 131 (2023) no.26, 262501 doi:10.1103/PhysRevLett.131.262501 [arXiv:2405.14305 [nucl-ex]].

[2] M. Ley, L. Knafla, J. Jolie, A. Esmaylzadeh, A. Harter, A. Blazhev, C. Fransen, A. Pfeil, J. M. Re'gis and P. Van Isacker, "Life-time measurements in $^{92}$Mo: Investigation of seniority conservation in the N=50 isotones," Phys. Rev. C 108 (2023) no.6, 064313 doi:10.1103/PhysRevC.108.064313

[3] M. Sguazzin, B. Jurado, J. Pibernat, J. A. Swartz, M. Grieser, J. Glorius, Y. A. Litvinov, J. Adamczewski-Musch, P. Alfaut and P. Ascher, et al. "First measurement of the neutron-emission probability with a surrogate reaction in inverse kinematics at a heavy-ion storage ring," [arXiv:2312.13742 [nucl-ex]].

[4] E. Ahlgren Cederlöf, T. Ba'ck, J. Nyberg, C. Qi, A. Atac, H. Badran, T. Braunroth, T. Calverley, D. M. Cox and M. Doncel, et al. "Lifetime measurement of the yrast $2^+$ state in $^{118}$Te," Eur. Phys. J. A 59 (2023) no.12, 300 doi:10.1140/epja/s10050-023-01212-3

[5] Q. Fable et al. [INDRA and INDRA-FAZIA], "Isospin diffusion from Ca40,48+Ca40,48 experimental data at Fermi energies: Di- rect comparisons with transport model calculations," Phys. Rev. C 109 (2020) no.6, 064605 doi:10.1103/PhysRevC.109.064605 [arXiv:2312.01763 [nucl-ex]].

[6] J. Lois-Fuentes, B. Ferna'ndez-Dom'inguez, X. Pereira-Lo'pez, F. Delaunay, W. N. Catford, A. Matta, N. A. Orr, T. Duguet, T. Otsuka and V. Soma', et al. "Low-lying structure of $^{15}$C: Information on the N=8 shell gap," EPJ Web Conf. 290 (2023), 09008 doi:10.1051/epjconf/202329009008

[7] D. Ferna'ndez, M. Caamaño, D. Ramos, A. Lemasson, M. Rejmund, H. A'lvarez-Pol, L. Audouin, J. D. Frankland, B. Ferna'ndez-Dom'inguez and E. Galiana-Baldo', et al. "Experimental study of high-energy fission and quasi-fission with fusion- induced fission reactions at VAMOS++," EPJ Web Conf. 290 (2023), 02012 doi:10.1051/epjconf/202329002012

[8] M. Lozano-Gonza'lez, B. Ferna'ndez-Dom'inguez, J. Lois-Fuentes and T. Roger, "Event reconstruction in ACTAR TPC: Adaptation for transfer experiments," EPJ Web Conf. 290 (2023), 01006 doi:10.1051/epjconf/202329001006

[9] Vite'z-Sveiczer, A. Algora, G. G. Kiss, B. Rubio, A. I. Morales, P. Sarriguren, G. de Angelis, F. Recchia, S. Nishimura and J. Agramunt, et al. "The β-decay of $^{71}$Kr: Precise measurement of the half-life," EPJ Web Conf. 290 (2023), 02021 doi:10.1051/epjconf/202329002021

[10] J. L. Rodríguez-Sa'nchez, M. Feijoo, J. Benlliure, A. Chatillon, J. Ta'ieb, L. Audouin, H. Alvarez-Pol, Y. Ayyad, G. Be'lier and G. Boutoux, et al. "Fragmentation-induced fission reactions of $^{236}$U in inverse kinematics to investigate the pre-fragment angular momentum parameterizations," EPJ Web Conf. 290 (2023), 02016 doi:10.1051/epjconf/202329002016

[11] Le Fe`vre, M. Colonna, G. Verde, K. Agarwal, J. Aichelin, T. Aumann, A. Chbihi, M. D. Cozma, E. De Filippo and H. Elfner, et al. "Long range plans to study the nuclear equation-of-state from sub- to supra-saturation densities with heavy-ion collisions," EPJ Web Conf. 290 (2023), 10004 doi:10.1051/epjconf/202329010004

[12] W. Urban, M. Czerwiński, G. de France, M. Jentschel, U. Ko¨ster, P. Mutti, T. Rzaca-Urban and J. Wis`niewski, "Directional- polarization correlations using EXILL," JINST 18 (2023) no.11, P11031 doi:10.1088/1748-0221/18/11/P11031

[13] A. Leviatan, N. Gavrielov and F. Iachello, "Intertwined quantum phase transitions in odd-mass Nb isotopes," [arXiv:2311.17127 [nucl-th]].

[14] M. Markova, P. von Neumann-Cosel and E. Litvinova, "Systematics of the low-energy electric dipole strength in the Sn isotopic chain," [arXiv:2311.14525 [nucl-ex]].

[15] C. Agodi, F. Cappuzzello, G. Cardella, G. A. P. Cirrone, E. De Filippo, A. Di Pietro, A. Gargano, M. La Cognata, D. Mascali and G. Milluzzo, et al. "Nuclear physics midterm plan at LNS," Eur. Phys. J. Plus 138 (2023) no.11, 1038 doi:10.1140/epjp/s13360-023-04358-7

[16] J. L. Wood and P. Van Isacker, "Remembering David J. Rowe," SciPost Phys. Proc. 14 (2023), 013 doi:10.21468/SciPostPhysProc.14.013

[17] G. Pasqualato, S. Ansari, J. S. Heines, V. Modamio, A. Go¨rgen, W. Korten, J. Ljungvall, E. Cle'ment, J. Dudouet and A. Lemas- son, et al. "Shape evolution in even-mass $^{98-104}$Zr isotopes via lifetime measurements using the γγ-coincidence technique," Eur. Phys. J. A 59 (2023) no.11, 276 doi:10.1140/epja/s10050-023-01172-8

[18] M. Markova, A. C. Larsen, P. von Neumann-Cosel, E. Litvinova, A. Choplin, S. Goriely, S. Martinet, L. Siess, M. Guttormsen and F. Pogliano, et al. "Systematic study of the low-lying electric dipole strength in Sn isotopes and its astrophysical implications," Phys. Rev. C 109 (2020) no.5, 054311 doi:10.1103/PhysRevC.109.054311 [arXiv:2311.08864 [nucl-ex]].

[19] A. Rebillard-Soulie', R. Bougault, H. Pais, B. Borderie, A. Chbihi, C. Ciampi, Q. Fable, J. Frankland, E.
Galichet and T. Ge'nard, et al. "Isoscaling in dilute warm nuclear systems," J. Phys. G 51 (2024) no.1, 015104 doi:10.1088/1361-6471/ad0edd [arXiv:2311.05392 [nucl-ex]].

[20] A. Savalle and O. Kamalou, "History and Prospectives of GANIL," JACoW CYCLOTRONS2022 (2023), TUAO01 doi:10.18429/JACoW-CYCLOTRONS2022-TUAO01

[21] D. Belverge, P. Leconte, B. Geslot, G. Kessedjian, P. Mutti, F. Rodiac, E. Pirovano, B. Lutz, X. Ledoux and L. Mathieu, et al. "New experiment for measuring the delayed neutron yields of 238U fission in the range 1 MeV to 19 MeV," EPJ Web Conf. 288 (2023), 04016 doi:10.1051/epjconf/202328804016

[22] P. Van Isacker, A. Algora, A. Vite'z-Sveiczer, G. G. Kiss, S. E. A. Orrigo, B. Rubio and P. Aguilera, "Gamow-Teller Beta Decay and Pseudo-SU(4) Symmetry," Symmetry 15 (2023) no.11, 2001 doi:10.3390/sym15112001

[23] L. Nies, L. Canete, D. D. Dao, S. Giraud, A. Kankainen, D. Lunney, F. Nowacki, B. Bastin, M. Stryjczyk and P. Ascher, et al. "Further Evidence for Shape Coexistence in Zn79m near Doubly Magic Ni78," Phys. Rev. Lett. 131 (2023) no.22, 222503 doi:10.1103/PhysRevLett.131.222503 [arXiv:2310.16915 [nucl-ex]].

[24] S. Hudan, H. Desilets, R. Kumar, R. T. deSouza, C. Ciampi, A. Chbihi and K. W. Brown, "Influence of additional neutrons on the fusion cross section beyond the N=8 shell," Phys. Rev. C 109 (2024) no.1, L011601 doi:10.1103/PhysRevC.109.L011601 [arXiv:2310.06776 [nucl-ex]].

[25] A. Khandelwal, J. E. Ducret, L. Maunoury and L. Garrigues, "Simulation modeling and electron energy distribution function studies of an electron cyclotron resonance source with a new magnetic topology," Phys. Rev. Accel. Beams 26 (2023) no.10, 103501 doi:10.1103/PhysRevAccelBeams.26.103501

[26] P. Pawlowski, J. Brzychczyk, N. Buyukcizmeci, H. T. Johansson, W. Trautmann, A. Wieloch, P. Adrich, T. Aumann, T. Bar-czyk and S. Bianchin, et al. "Neutrons from projectile fragmentation at 600 MeV/nucleon," Phys. Rev. C 108 (2023) no.4, 044610 doi:10.1103/PhysRevC.108.044610 [arXiv:2310.00409 [nucl-ex]].

[27] M. Di Giacomo, C. Barthe-Dejean, B. Jacquot, S. Leloir and A. K. Orduz, "Upgrade of the medium energy dump geometry for the SPIRAL2 single bunch selector," JACoW IPAC2023 (2023), THPA190 doi:10.1088/1742-6596/2687/8/082041

[28] M. H. Moscatello, D. Ackermann, M. Di Giacomo, J. Dumas, A. Fournier, C. Haquin, C. Jamet, M. Michel, G. Normand and C. Peacelle, et al. "NEWGAIN project at GANIL-SPIRAL2: design of the new heavy ion injector for the superconducting linac," JACoW IPAC2023 (2023), TUPA193 doi:10.18429/JACoW-IPAC2023-TUPA193

[29] G. Normand, J. M. Lagniel and A. Orduz, "Strategies for SPIRAL2 linac heavy-ion beam tuning," JACoW IPAC2023 (2023), TUPA192 doi:10.18429/JACoW-IPAC2023-TUPA192

[30] J. Dumas, O. Kamalou, A. Orduz and E. Traykov, "Beam dynamics in the NEWGAIN project at GANIL-SPIRAL2," JACoW IPAC2023 (2023), WEPL035 doi:10.18429/JACoW-IPAC2023-WEPL035

[31] A. Orduz, P. E. Bernaudin, M. Di Giacomo, C. Jamet, J. M. Lagniel, G. Normand, A. Savalle and D. Uriot, "Commissioning and operation of the SPIRAL2 SC linac," JACoW IPAC2023 (2023), FRXD3 doi:10.18429/JACoW-IPAC2023-FRXD3

[32] Chance, T. Da Silva, B. Dalena and A. Ghribi, "Status and plans for the high energy booster of the future electron-positron collider FCC-ee," JACoW IPAC2023 (2023), MOPL070 doi:10.18429/JACoW-IPAC2023-MOPL070

[33] F. Osswald, E. Traykov, J. C. Thomas, J. Michaud, M. Heine and T. Durand, "Beam loss monitoring through emittance growth control and feedback with design," JACoW IPAC2023 (2023), TUPA082 doi:10.18429/JACoW-IPAC2023-TUPA082

[34] R. Abukeshek, H. Abualrob, A. Stocchi, L. Perrot, A. Fomin, J. Michaud, A. Bogacz, J. Benesch and B. Jacquot, "Mag- netic Design of the Commutational Magnet and Quadrupoles for PERLE Accelerator," JACoW IPAC2023 (2023), MOPA023 doi:10.1088/1742-6596/2687/2/022023

[35] Dalena, T. Da Silva, A. Chance' and A. Ghribi, "Definition of tolerances and corrector strengths for the orbit control of the High-Energy Booster ring of the future electron-positron collider," JACoW IPAC2023 (2023), MOPL054 doi:10.1088/1742-6596/2687/2/022004

[36] A. Esper, M. H. Stodel, H. Savajols, M. Authier, M. Aburas, F. Carville, A. Drouart, B. Jacquot, A. Lefevre and F. Esnault, "Su- perconducting multipole triplet field measurements," JACoW IPAC2023 (2023), THPA043 doi:10.1088/1742-6596/2687/7/072027

[37] L. G. Sarmiento, T. Roger, J. Giovinazzo, B. A. Brown, B. Blank, D. Rudolph, A. Kankainen, H. Alvarez-Pol, A. Arokia Raj and P. Ascher, et al. "Elucidating the nature of the proton radioactivity and branching ratio on the first proton emitter discovered $^{53m}$Co," Nature Commun. 14 (2023) no.1, 5961 doi:10.1038/s41467-023-39389-2

[38] M. Q. Hlatshwayo, J. Novak and E. Litvinova, "Quantum benefit of the quantum equation of motion for the strongly coupled many-body problem," Phys. Rev. C 109 (2024) no.1, 014306 doi:10.1103/PhysRevC.109.014306 [arXiv:2309.10179 [nucl-th]].

[39] N. Gavrielov, J. E. Garcia-Ramos, P. Van Isacker and A. Leviatan, "Persistent vibrational structure in $^{110-116}$Cd," Phys. Rev. C 108 (2023) no.3, L031305 doi:10.1103/PhysRevC.108.L031305 [arXiv:2309.09285 [nucl-th]].

[40] N. Saneesh, D. Arora, A. Chatterjee, N. Kumar, A. Parihari, C. Kumar, I. Ahmed, S. Kumar, M. Kumar and A. Jhin- gan, et al. "Impact of multichance fission on fragment-neutron correlations in Pa227," Phys. Rev. C 108 (2023) no.3, 034609 doi:10.1103/PhysRevC.108.034609

[41] G. Rucher, K. Prigent, C. Simard, A. M. Frelin, M. Coquemont-Guyot, N. Elie, N. Delcroix, N. Perzo, R. Guinamard
and L. Berger, et al. "Targeted Radiation Exposure Induces Accelerated Aortic Valve Remodeling in ApoE-/- Mice," Journal of Clinical Medicine **12** (2023) no.18, 5854 doi:10.3390/jcm12185854

[42] A. Bahini, P. von Neumann-Cosel, J. Carter, I. T. Usman, N. N. Arsenyev, A. P. Severyukhin, E. Litvinova, R. W. Fearick, R. Neveling and P. Adsley, et al. "Fine structure of the isoscalar giant monopole resonance in Ni58, Zr90, Sn120, and Pb208," Phys. Rev. C **109** (2024) no.1, 014325 doi:10.1103/PhysRevC.109.014325 [arXiv:2309.04016 [nucl-ex]].

[43] H. D. Thi, A. F. Fantina and F. Gulminelli, "Light clusters in the liquid proto-neutron star inner crust," Eur. Phys. J. A **59** (2023) no.12, 292 doi:10.1140/epja/s10050-023-01199-x [arXiv:2309.01533 [nucl-th]].

[44] H. Dinh Thi, A. F. Fantina and F. Gulminelli, "The proto-neutron star inner crust in a multi-component plasma approach," Astron. Astrophys. **677** (2023), A174 doi:10.1051/0004-6361/202346606 [arXiv:2309.01527 [astro-ph.HE]].

[45] Blank, J. C. Thomas, M. Gerbaux, P. Ascher, D. Atanasov, F. Cresto, Q. De'lignac, A. de Roubin, M. Flayol and Q. Gendre, et al. "Precise mass measurement of the $^{32}$S member of the (A=32, T=2) quintet of analogue states," J. Phys. Conf. Ser. **2586** (2023) no.1, 012060 doi:10.1088/1742-6596/2586/1/012060

[46] N. Goyal, S. Daumas-Tschopp, F. De Oliveira Santos, P. Delahaye, X. Flechard, J. M. Fontbonne, E. Lienard, L. M. Motilla, J. Perronnel and G. Quemener, et al. "Detection of recoil ion in the beta decay of laser oriented trapped radioactive isotopes for the MORA Project," J. Phys. Conf. Ser. **2586** (2023) no.1, 012142 doi:10.1088/1742-6596/2586/1/012142

[47] M. Forge, O. Dorvaux, A. Lopez-Martens, K. Kessaci, B. J. P. Gall, K. Hauschild, Z. Asfari, R. Chakma, A. V. Yeremin and M. L. Chelnokov, et al. "New results on the decay spectroscopy of $^{254}$No with GABRIELA@SHELS," J. Phys. Conf. Ser. **2586** (2023) no.1, 012083 doi:10.1088/1742-6596/2586/1/012083

[48] A. F. Fantina and F. Gulminelli, "Nuclear physics inputs for dense-matter modelling in neutron stars. The nuclear equation of state," J. Phys. Conf. Ser. **2586** (2023) no.1, 012112 doi:10.1088/1742-6596/2586/1/012112 [arXiv:2311.07144 [astro-ph.HE]].

[49] Brugnara, A. Gottardo, M. Assie', D. Mengoni, A. Lemasson, E. Clement, F. Flavigny, D. Ramos, F. Galtarossa and A. Matta, et al. "The $^{46}$Ar($^{3}$He, d)$^{47}$K direct reaction as a probe of the $^{46}$Ar proton wavefunction," J. Phys. Conf. Ser. **2586** (2023) no.1, 012073 doi:10.1088/1742-6596/2586/1/012073

[50] L. M. Donaldson, P. Adsley, A. Banu, S. Bassauer, B. Bastin, C. A. Bertulani, J. W. Bru"mmer, J. Carter, G. R. J. Cooper and R. W. Fearick, et al. "Nuclear-structure experiments at iThemba LABS to investigate discrepancies between (p, p') and (y, xn) data," J. Phys. Conf. Ser. **2586** (2023) no.1, 012068 doi:10.1088/1742-6596/2586/1/012068

[51] A. Ciampi et al. [INDRA-FAZIA], "Nuclear symmetry energy at work in heavy ion reactions: new results from the INDRA-FAZIA apparatus," J. Phys. Conf. Ser. **2586** (2023) no.1, 012039 doi:10.1088/1742-6596/2586/1/012039

[52] M. Sguazzin, J. A. Swartz, B. Jurado, J. Pibernat, M. Grieser, J. Glorius, Y. A. Litvinov, R. Reifarth, K. Blaum and P. Alfaurt, et al. "Determining neutron-induced reaction cross sections through surrogate reactions at storage rings," J. Phys. Conf. Ser. **2586** (2023) no.1, 012082 doi:10.1088/1742-6596/2586/1/012082

[53] M. Le Joubioux, H. Savajols, W. Mittig, X. Fle'chard, L. Hayen, Y. E. Penionzhkevich, D. Ackermann, C. Borcea, L. Caceres and P. Delahaye, et al. "Search for a Neutron Dark Decay in He6," Phys. Rev. Lett. **132** (2024) no.13, 132501 doi:10.1103/PhysRevLett.132.132501 [arXiv:2308.16536 [nucl-ex]].

[54] Y. Kondo, N. L. Achouri, H. A. Falou, L. Atar, T. Aumann, H. Baba, K. Boretzky, C. Caesar, D. Calvet and H. Chae, et al. "First observation of $^{28}$O," Nature **620** (2023) no.7976, 965-970 [erratum: Nature **623** (2023) no.7988, E13] doi:10.1038/s41586-023-06352-6

[55] C. Ciampi et al. [INDRA-FAZIA], "Quasiprojectile breakup and isospin equilibration at Fermi energies: Potential indication of longer projectile-target contact times," Phys. Rev. C **108** (2023) no.5, 054611 doi:10.1103/PhysRevC.108.054611 [arXiv:2308.15077 [nucl-ex]].

[56] A. Jaries, M. Stryjczyk, A. Kankainen, L. Al Ayoubi, O. Beliuskina, P. Delahaye, T. Eronen, M. Flayol, Z. Ge and W. Gins, et al. "High-precision Penning-trap mass measurements of Cd and In isotopes at JYFLTRAP remove the fluctuations in the two-neutron separation energies," Phys. Rev. C **108** (2023) no.6, 064302 doi:10.1103/PhysRevC.108.064302 [arXiv:2308.15270 [nucl-ex]].

[57] E. Litvinova, "On the dynamical kernels of fermionic equations of motion in strongly-correlated media," Eur. Phys. J. A **59** (2023) no.12, 291 doi:10.1140/epja/s10050-023-01198-y [arXiv:2308.07574 [nucl-th]].

[58] M. Ballan, S. Bottoni, M. Caamaño, A. Caciolli, M. Campostrini, M. Cicerchia, F. C. L. Crespi, S. Cristallo, D. Dell'Aquila and R. Depalo, et al. "Nuclear physics midterm plan at Legnaro National Laboratories (LNL)," Eur. Phys. J. Plus **138** (2023) no.8, 709 doi:10.1140/epjp/s13360-023-04249-x

[59] J. Wis'niewski, W. Urban, T. Rzaca-Urban, K. Sieja, A. Blanc, M. Jentschel, C. Micheagnoli, P. Mutti, U. Ko"ster and G. de France, et al. "Structure of N=56 isotones with $36 \le Z \le 42$ protons," Phys. Rev. C **108** (2023) no.2, 024302 doi:10.1103/PhysRevC.108.024302

[60] T. Rzaca-Urban, W. Urban, A. Blanc, M. Jentschel, P. Mutti, U. Ko"ster, G. de France, G. S. Simpson and C. A. Ur, "Low-spin excitations in Zr95," Phys. Rev. C **108** (2023) no.1, 014324 doi:10.1103/PhysRevC.108.014324

[61] A. Camaiani, S. Barlini, A. A. Stefanini, G. Casini, H. Alvarez-Pol, A. Arokiaraj, L. Baldesi, R. Bolzonella, G. Cardella and C. Ciampi, et al. "Energy loss profile measurements using the ACTAR TPC demonstrator active target,"
Nucl. Instrum. Meth. B **542** (2023), 188-194 doi:10.1016/j.nimb.2023.07.001

[62] E. Cle'ment, A. Bracco, A. Gadea and J. Simpson, "Organisation of the AGATA collaboration and physics campaigns," Eur. Phys. J. A **59** (2023) no.7, 152 doi:10.1140/epja/s10050-023-01057-w

[63] Thisse, M. Lebois, D. Verney, J. N. Wilson, N. Jovanc'evic', M. Rudigier, R. Canavan, D. Etasse, P. Adsley and A. Algora, et al. "Study of N = 50 gap evolution around Z = 32: new structure information for ⁸²Ge," Eur. Phys. J. A **59** (2023) no.7, 153 doi:10.1140/epja/s10050-023-01051-2

[64] Rey-herme et al. [IGISOL], "Level structure of Ac221 and Fr217 from decay spectroscopy, and reflection asymmetry in Ac221," Phys. Rev. C **108** (2023) no.1, 014304 doi:10.1103/PhysRevC.108.014304

[65] M. Colonna and A. Navin, "EURO-LABS: Europe's Super Community of Subatomic Researchers," Nucl. Phys. News **33** (2023) no.2, 3-4 doi:10.1080/10619127.2023.2198906

[66] S. Chakraborty, S. Bhattacharyya, R. Banik, S. Bhattacharya, G. Mukherjee, C. Bhattacharya, S. Biswas, S. Rajbanshi, S. Dar and S. Nandi, et al. "Search for the origin of wobbling motion in the A≈130 region: The case of Xe131," Phys. Rev. C **107** (2023) no.6, 064318 doi:10.1103/PhysRevC.107.064318 [arXiv:2311.09713 [nucl-ex]].

[67] D. A. Nesterenko, J. Ruotsalainen, M. Stryjczyk, A. Kankainen, L. Al Ayoubi, O. Beliuskina, P. Delahaye, T. Eronen, M. Flayol and Z. Ge, et al. "High-precision measurements of low-lying isomeric states in In120-124 with the JYFLTRAP double Penning trap," Phys. Rev. C **108** (2023) no.5, 054301 doi:10.1103/PhysRevC.108.054301 [arXiv:2306.11505 [nucl-ex]].

[68] Wang, M. Yasuda, Y. Kondo, T. Nakamura, J. A. Tostevin, K. Ogata, T. Otsuka, A. Poves, N. Shimizu and K. Yoshida, et al. "Intruder configurations in ²⁹Ne at the transition into the island of inversion: Detailed structure study of ²⁸Ne," Phys. Lett. B **843** (2023), 138038 doi:10.1016/j.physletb.2023.138038 [arXiv:2306.16189 [nucl-ex]].

[69] A. Lemasson, J. Dudouet, M. Rejmund, J. Ljungvall, A. Goğrgen and W. Korten, "Advancements of γ-ray spectroscopy of isotopi- cally identified fission fragments with AGATA and VAMOS++," Eur. Phys. J. A **59** (2023) no.6, 134 doi:10.1140/epja/s10050-023-01053-0 [arXiv:2306.10818 [nucl-ex]].

[70] J. Collado, S. Capra, A. Pullia, N. Karkour, C. Houarner, V. Gonzalez, G. Wittwer, A. Boujrad, M. Kogimtzis and J. Lawson, et al. "AGATA phase 2 advancements in front-end electronics," Eur. Phys. J. A **59** (2023) no.6, 133 doi:10.1140/epja/s10050-023-01045-0

[71] J. D. Ovejas, I. Martel, D. Dell'Aquila, L. Acosta, J. L. Aguado, G. de Angelis, M. J. G. Borge, J. A. Briz, A. Chbihi and G. Colucci, et al. "Suppression of Coulomb-nuclear interference in the near-barrier elastic scattering of 17Ne from 208Pb," Phys. Lett. B **843** (2023), 138007 doi:10.1016/j.physletb.2023.138007

[72] N. Michel, W. Nazarewicz and M. Płoszajczak, "Description of the Proton-Decaying 02+ Resonance of the α Particle," Phys. Rev. Lett. **131** (2023) no.24, 242502 doi:10.1103/PhysRevLett.131.242502 [arXiv:2306.05192 [nucl-th]].

[73] J. P. Linares Fernandez, N. Michel, M. Płoszajczak and A. Mercenne, "Description of Be7 and Li7 within the Gamow shell model," Phys. Rev. C **108** (2023) no.4, 044616 doi:10.1103/PhysRevC.108.044616 [arXiv:2306.05215 [nucl-th]].

[74] A. Lemasson and M. Rejmund, "Fast trajectory reconstruction techniques for the large acceptance magnetic spectrometer VA- MOS++," Nucl. Instrum. Meth. A **1054** (2023), 168407 doi:10.1016/j.nima.2023.168407 [arXiv:2307.03752 [physics.ins-det]].

[75] S. Raeder, B. Andelic', J. Auler, M. Block, P. Chauveau, P. Chhetri, A. Claessens, A. de Roubin, C. E. Du'llmann and R. Ferrer, et al. "Opportunities and limitations of in-gas-cell laser spectroscopy of the heaviest elements with RADRIS," Nucl. Instrum. Meth. B **541** (2023), 370-374 doi:10.1016/j.nimb.2023.04.044

[76] Brunet, M. Michel, G. De France, V. Desmezie`res, B. Jacquot, C. Hocini, S. Ferey, J. Gueret, L. Rossard and M. Morisset, et al. "Design of a high power solid target for ²¹¹At," EPJ Web Conf. **285** (2023), 07001 doi:10.1051/epjconf/202328507001

[77] P. Jardin, V. Bosquet, S. Damoy, G. Fre'mont, F. Perocheau and M. MacCormick, "Ni target development for the TULIP project," EPJ Web Conf. **285** (2023), 08001 doi:10.1051/epjconf/202328508001

[78] A. Korichi, E. Cle'ment, N. Dosme, E. Legay, O. Ste'zowski, A. Goasduff, Y. Aubert, J. Dudouet, S. Elloumi and P. Gauron, et al. "AGATA DAQ-box: a unified data acquisition system for different experimental conditions," Eur. Phys. J. A **59** (2023) no.9, 211 doi:10.1140/epja/s10050-023-01091-8 [arXiv:2305.18653 [physics.ins-det]].

[79] Y. Cho, Y. H. Kim, S. Choi, J. Park, S. Bae, K. I. Hahn, Y. Son, A. Navin, A. Lemasson and M. Rejmund, et al. "Paricle identifica- tion at VAMOS++ with machine learning techniques," Nucl. Instrum. Meth. B **541** (2023), 240-242 doi:10.1016/j.nimb.2023.05.053 [arXiv:2311.07103 [physics.ins-det]].

[80] R. M. Pe'rez-Vidal, F. Galtarossa, T. Mijatovic', S. Szilner, I. Zanon, D. Brugnara, J. Pellumaj, M. Ciemala, J. J. Valiente-Dobo'n and L. Corradi, et al. "Nuclear structure advancements with multi-nucleon transfer reactions," Eur. Phys. J. A **59** (2023) no.5, 114 [erratum: Eur. Phys. J. A **59** (2023) no.6, 143] doi:10.1140/epja/s10050-023-01027-2

[81] Michaud, P. Alfaurt, A. Balana, B. Blank, L. Daudin, T. Kurtukian-Nieto, B. Lachacinski, L. Serani, J. C. Thomas and F. Varenne, "Commissioning of the DESIR high-resolution mass separator," Nucl. Instrum. Meth. B **541** (2023), 161-164 doi:10.1016/j.nimb.2023.05.013

[82] P. Jardin, M. MacCormick, V. Bosquet, P. Chauveau, S. Damoy, P. Delahaye, M. Dubois, M. Fadil, M. Lalande and C. Michel, et al. "Sub-millisecond atom-to-ion transformation in the TULIP ISOL system," Nucl. Instrum. Meth. A **1055**
(2023), 168332 doi:10.1016/j.nima.2023.168332

[83] P. Chauveau, V. Bosquet, S. Damoy, P. Delahaye, M. Dubois, P. Jardin, M. Lalande, L. Maunoury and J. C. Thomas, "Latest improvements of the SPIRAL1 facility at GANIL," Nucl. Instrum. Meth. B 541 (2023), 61-64 doi:10.1016/j.nimb.2023.05.003

[84] Y. Son, Y. H. Kim, Y. Cho, S. Choi, S. Bae, K. I. Hahn, J. Park, A. Navin, A. Lemasson and M. Rejmund, et al. "CATLIFE (Complementary Arm for Target Like FragmEnts): Spectrometer for Target like fragments at VAMOS++," Nucl. Instrum. Meth. B 540 (2023), 234-236 doi:10.1016/j.nimb.2023.04.024 [arXiv:2311.16165 [physics.ins-det]].

[85] V. Bosquet, P. Jardin, M. MacCormick and C. Michel, "The TULIP project: First on-line result and near future," Nucl. Instrum. Meth. B 541 (2023), 106-108 doi:10.1016/j.nimb.2023.04.046 [arXiv:2304.14416 [physics.ins-det]].

[86] A. Ajayakumar, J. Romans, M. Authier, Y. Balasmeh, A. Brizard, F. Boumad, L. Caceres, J. F. Cam, A. Claessens and S. Damoy, et al. "In-gas-jet laser spectroscopy with S³-LEB," Nucl. Instrum. Meth. B 539 (2023), 102-107 doi:10.1016/j.nimb.2023.03.020

[87] J. Valiente-Doboń, R. Menegazzo, A. Goasduff, D. Agguiaro, P. Aguilera, F. Angelini, M. Balogh, D. Bazzacco, J. Benito and G. Benzoni, et al. "Conceptual design of the AGATA 2π array at LNL," Nucl. Instrum. Meth. A 1049 (2023), 168040 doi:10.1016/j.nima.2023.168040

[88] H. Dinh Thi, A. F. Fantina and F. Gulminelli, "The proto-neutron star inner crust in the liquid phase," Astron. Astrophys. 672 (2023), A160 doi:10.1051/0004-6361/202245061 [arXiv:2304.01584 [astro-ph.HE]].

[89] M. Kanafani, X. Flechard, O. Naviliat-Cuncic, G. D. Chung, S. Leblond, E. Lieńard, X. Mougeot, G. Queméner, A. S. D. Filippo and J. C. Thomas, "Precision measurements in the beta decay of ⁶He," EPJ Web Conf. 282 (2023), 01010 doi:10.1051/epjconf/202328201010

[90] B. Dalena, T. Da Silva, A. Chance and A. Ghribi, "Definition of tolerances and corrector strengths for the orbit control of the High-Energy Booster ring of the future electro-positron collider," [arXiv:2303.17996 [physics.acc-ph]].

[91] G. Lhersonneau, P. Jones, M. Fadil, T. Malkiewicz and W. H. Trzaska, "Experimental cross sections in fission of natural uranium induced by a neutron spectrum of 12.4-MeV average energy," Eur. Phys. J. Plus 138 (2023) no.3, 303 doi:10.1140/epjp/s13360-023-03912-7

[92] C. Frosin et al. [INDRA-FAZIA], "Examination of cluster production in excited light systems at Fermi energies from new experimental data and comparison with transport model calculations," Phys. Rev. C 107 (2023) no.4, 044614 doi:10.1103/PhysRevC.107.044614 [arXiv:2303.17390 [nucl-ex]].

[93] S. Piantelli et al. [FAZIA], "Characterization of the breakup channel in the asymmetric systems Ca40,48+C12 at 25 and 40 MeV/nucleon," Phys. Rev. C 107 (2023) no.4, 044607 doi:10.1103/PhysRevC.107.044607 [arXiv:2303.13215 [nucl-ex]].

[94] Á. Koszoru's, M. Block, P. Campbell, B. Cheal, R. P. de Groote, W. Gins, I. D. Moore, A. Ortiz-Cortes, A. Raggio and J. War-binek, "High-precision measurements of the hyperfine structure of cobalt ions in the deep ultraviolet range," Sci. Rep. 13 (2023) no.1, 4783 doi:10.1038/s41598-023-31378-1

[95] F. Osswald, E. Traykov, T. Durand, M. Heine, J. Michaud and J. C. Thomas, "Challenges in low losses and large acceptance ion beam transport," [arXiv:2303.06969 [physics.acc-ph]].

[96] M. Urquiza-Gonzalez, M. Au, C. Bernerd, M. Bissell, B. van den Borne, K. Chrysalidis, T. E. Cocolios, V. N. Fedosseev, K. T. Flanagan and R. G. Garcia Ruiz, et al. "Benchmark evaluation for a single frequency continuous wave OPO seeded pulsed dye amplifier for high-resolution laser spectroscopy," doi:10.1117/12.2646665

[97] O. Steżowski, J. Dudouet, A. Goasduff, A. Korichi, Y. Aubert, M. Balogh, G. Baulieu, D. Bazzacco, S. Brambilla and D. Brugnara, et al. "Advancements in software developments," Eur. Phys. J. A 59 (2023) no.5, 119 doi:10.1140/epja/s10050-023-01025-4 [arXiv:2303.01275 [physics.ins-det]].

[98] D. Ackermann, "Nuclear Isomers in the Heaviest Nuclei — the Odd Nucleon as a Sensitive Probe of Low-lying Nuclear Structure," Acta Phys. Polon. Supp. 16 (2023) no.4, 9 doi:10.5506/APhysPolBSupp.16.4-A9

[99] N. Cieplicka-Oryńczak, B. Fornal, M. Ciemała, M. Kmiecik, A. Maj, J. Łukasik, P. Pawłowski, B. Sowicki, B. Wasilewska and M. Ziebliński, et al. "M4 Resonances in Light Nuclei Studied at CCB," Acta Phys. Polon. Supp. 16 (2023) no.4, A4 doi:10.5506/APhysPolBSupp.16.4-A4

[100] J. Romero, K. Auranen, M. Block, A. D. Briscoe, T. Eronen, W. Gins, T. Grahn, P. T. Greenlees, A. Illana and R. Julin, et al. "Nuclear Reaction Studies and Prospects for the New MARA-LEB Facility," Acta Phys. Polon. Supp. 16 (2023) no.4, A12 doi:10.5506/APhysPolBSupp.16.4-A12

[101] A. Utepov, D. Ackermann, C. Stodel, A. Lemasson, D. Ramos, M. Rejmund, E. Clement, B. Jacquot, J. Piot and J. E. Ducret, et al. "Multinucleon Transfer Reactions in the $^{238}$U + $^{238}$U System Studied with the VAMOS+AGATA+ID-Fix," Acta Phys. Polon. Supp. 16 (2023) no.4, A11 doi:10.5506/APhysPolBSupp.16.4-A11

[102] J. P. Linares Fernandez, M. Płoszajczak and N. Michel, "Gamow Shell Model Description of $^7$Li and Elastic Scattering Reaction $^4$He($^3$H,$^3$H)$^4$He," Acta Phys. Polon. Supp. 16 (2023) no.4, 22 doi:10.5506/APhysPolBSupp.16.4-A22 [arXiv:2304.00602 [nucl-th]].

[103] P. E. Georgoudis, "A + 2n compound nuclei and the unitary limit in nuclear physics," J. Phys. Conf. Ser. 2453 (2023) no.1, 012023 doi:10.1088/1742-6596/2453/1/012023 [arXiv:2304.02400 [nucl-th]].

[104] D. Simon, T. Cadoux, E. Fernandez Mora, B. Hervieu, C. Berriaud, M. Segreti, G. Minier, E. Rochepault, R. Vallcorba and A. Sinanna, et al. "Design of ASTERICS: A Superconducting 28 GHz ECR Ion Source Magnet for GANIL,"
[105] Sguazzin, B. Jurado, J. Pibernat, J. A. Swartz, M. Grieser, J. Glorius, Y. A. Litvinov, R. Reifarth, K. Blaum and P. Alfaurt, et al. "Indirect measurements of neutron-induced reaction cross sections at storage rings," EPJ Web Conf. 279 (2023), 11006 doi:10.1051/epjconf/202327911006

[106] Lalanne, O. Sorlin, A. Poves, M. Assie', F. Hammache, S. Koyama, D. Suzuki, F. Flavigny, V. Girard-Alcindor and A. Lemasson, et al. "N=16 Magicity Revealed at the Proton Drip Line through the Study of Ca35," Phys. Rev. Lett. 131 (2023) no.9, 092501 doi:10.1103/PhysRevLett.131.092501 [arXiv:2302.14382 [nucl-ex]].

[107] D. P. Carrasco-Rojas, M. Williams, P. Adsley, L. Lamia, B. Bastin, T. Faestermann, C. Fouge'res, F. Hammache, D. S. Har-rouz and R. Hertenberger, et al. "Searching for resonance states in Ne22(p,y)Na23," Phys. Rev. C 108 (2023) no.4, 045802 doi:10.1103/PhysRevC.108.045802 [arXiv:2302.12939 [nucl-ex]].

[108] C. Haquin, O. Delahaye, C. Patard, F. Pillon, J. Pivard and G. Se'ne'cal, "How GANIL Plan to Use Web Technologies to Update the Control System User Interfaces," JACOBS PCAPAC2022 (2023), THO14 doi:10.18429/JACOBS-PCAPAC2022-THO14

[109] J. Lois-Fuentes, B. Fernandez-Dominguez, X. Pereira-Lopez, F. Delaunay, W. N. Catford, A. Matta, N. A. Orr, T. Duguet, T. Otsuka and V. Soma, et al. "Cross-shell states in 15C: A test for p-sd interactions," Phys. Lett. B 845 (2023), 138149 doi:10.1016/j.physletb.2023.138149 [arXiv:2302.08382 [nucl-ex]].

[110] A. Doudard, A. Corroyer-Dulmont, C. Jaudet, M. Bernaudin, S. Valable, X. Ledoux and A. Frelin-Labalme, "Application of a new spectral deconvolution method for in vitro dosimetry in assessment of targeted alpha therapy," Med. Phys. 50 (2023) no.6, 3762-3772 doi:10.1002/mp.16279

[111] D. Ramos, M. Caamaño, F. Target, C. Rodríguez-Tajes, A. Lemasson, C. Schmitt, L. Audouin, J. Benlliure, E. Casarejos and E. Clement, et al. "Experimental evidence of the effect of nuclear shells on fission dissipation and time," Phys. Rev. C 107 (2023) no.2, L021601 doi:10.1103/PhysRevC.107.L021601 [arXiv:2302.13856 [nucl-ex]].

[112] B. Bastin, J. Kiener, I. Deloncle, A. Coc, M. Pospelov, J. Mrazek, L. Lamia, D. Ackermann, P. Adsley and C. O. Bacri, et al. "Investigation of a light Dark Boson existence: The New JEDI project," EPJ Web Conf. 275 (2023), 01012 doi:10.1051/epjconf/202327501012

[113] D. Godos-Valencia, L. Acosta, P. Ascher, B. Blank, J. Giovinazzo, F. de Oliveira Santos, C. Fouge'res and A. M. Sa'nchez-Ben'itez, "Experimental studies of the $^{46}$Mn $\beta^+$-decay channel and spectroscopy of $^{46}$Cr at LISE-GANIL," EPJ Web Conf. 275 (2023), 02005 doi:10.1051/epjconf/202327502005

[114] E. Cle'ment, A. Lemasson, M. Rejmund, B. Jacquot, D. Ralet, C. Michelagnoli, D. Barrientos, P. Bednarczyk, G. Ben- zoni and A. J. Boston, et al. "Spectroscopic quadrupole moments in Xe124," Phys. Rev. C 107 (2023) no.1, 014324 doi:10.1103/PhysRevC.107.014324

[115] A. Sorensen, K. Agarwal, K. W. Brown, Z. Chajecki, P. Danielewicz, C. Drischler, S. Gandolfi, J. W. Holt, M. Kaminski and C. M. Ko, et al. "Dense nuclear matter equation of state from heavy-ion collisions," Prog. Part. Nucl. Phys. 134 (2024), 104080 doi:10.1016/j.ppnp.2023.104080 [arXiv:2301.13253 [nucl-th]].

[116] J. Angot, O. Tarvainen, P. Chauveau, S. Kosonen, T. Kalvas, T. Thuillier, M. Migliore and L. Maunoury, "The longitudinal en- ergy spread of ion beams extracted from an electron cyclotron resonance ion source," JINST 18 (2023) no.04, P04018 doi:10.1088/1748-0221/18/04/P04018 [arXiv:2301.07395 [physics.acc-ph]].

[117] A. Mercenne, N. Michel, J. P. Linares Ferna'ndez and M. Płoszajczak, "Gamow shell model description of the Ca40(d,p) transfer reaction," Phys. Rev. C 107 (2023) no.1, L011603 doi:10.1103/PhysRevC.107.L011603 [arXiv:2301.05419 [nucl-th]].

[118] Sguazzin, B. Jurado, J. Pibernat, J. A. Swartz, M. Grieser, J. Glorius, Y. A. Litvinov, R. Reifarth, K. Blaum and P. Alfaurt, et al. "Indirect measurements of neutron-induced reaction cross sections at heavy-ion storage rings," EPJ Web Conf. 284 (2023), 01008 doi:10.1051/epjconf/202328401008

[119] L. T. Bott, K. Go¨ bel, M. Heil, A. Kelic'-Heil, R. Reifarth, M. Aliotta, T. Almusidi, H. Alvarez-Pol, L. Atar and L. Atkins, et al. "Coulomb dissociation of $^{16}$O into $^{4}$He and $^{12}$C," EPJ Web Conf. 279 (2023), 04003 doi:10.1051/epjconf/202327904003

[120] D. Ferna'ndez, M. Caamaño, D. Ramos, A. Lemasson, M. Rejmund, H. A´ lvarez-Pol, L. Audouin, J. D. Frankland, B. Ferna'ndez-Dom'inguez and E. Galiana-Baldo', et al. "Experimental study of high-energy fission and quasi-fission dynamics with fusion-induced fission reactions at VAMOS++," EPJ Web Conf. 284 (2023), 04009 doi:10.1051/epjconf/202328404009

[121] A. Chatillon, G. Boutoux, T. Gorbinet, L. Grente, J. F. Martin, E. Pellereau, J. Taieb, H. Alvarez-Pol, L. Audouin and Y. Ayyad, et al. "Fission-fragment yields measured in Coulomb-induced fission of $^{234,235,236,238}$U and $^{237,238}$Np with the R$^3$B/SOFIA setup," EPJ Web Conf. 284 (2023), 04002 doi:10.1051/epjconf/202328404002
## II.CONFERENCE LIST

In 2023, GANIL hosted or organized different workshops and schools:

* "WS SOURCES" organised by Mickael Dubois, 18-19 May, 87 participants

* "Colloque GANIL" organised by Pierre Delahaye & Muriel Fallot, 25-29 September, 111 participants

* "19th Russbach School on Nuclear Astropysics" organised by Olivier Sorlin, 12-18 March, 64 participants

* "The 4th French-Czech "Barrande" Nuclear Research workshop" organised by François de Oliveira, Véronique Debord-Lazar and Jaromír Mrázek, 10-12 October, 37 participants.
## III.COMMITTEES

### 1. MEMBERS OF THE GANIL USERS EXECUTIVE COMMITTEE (GUEC)

Beatriz Fernandez Dominguez (USC, Spain) - chair

Franco Galtarossa (Padova, Italy)

Michal Ciemala (Krakow, Poland)

Hervé Savajols (GANIL, France)

Iolanda Matea (IJCLab, France)

John Frankland (GANIL, secretary and management liaison)

Marika Schleberger (University Duisburg-Essen, Germany)

Jose Lay (University of Sevilla, Spain)

### 2. MEMBERS OF THE PROGRAM ADVISORY COMMITTEE (PAC)

Mandate – March 2019-July 2024

DE OLIVEIRA François – GANIL, Caen, France

JUNGHANS Arnd - HZDR Dresde, Germany

LACROIX Denis - IJCLab, Paris Saclay, France

OBERTELLI Alexandre - TU Darmstadt, Germany

RIDIKAS Danas- IAEA Vienna, Austria

Mandate – February 2022 to February 2026

ASAI Masato - JAEA, Ibaraki, Japan

GAUDEFROY Laurent - CEA DAM, Bruyères-le-Châtel, France

LEIFELS Yvonne - GSI, Darmstadt, Germany

MORO Antonio - University Sevilla, Sevilla, Italy

OBERSTEDT Stephan - JRC Geel, Geel, Belgium

PETRI Marina - University York, Heslington, United Kingdom

TUMINO Aurora - University Kore, Enna, Italy

### 3. MEMBERS OF THE INTERDISCIPLINARY PROGRAM ADVISORY COMMITTEE (IPAC)

LORENZ Katharina - Instituto Superior Técnico (IST), Universidade de Lisboa, Instituto de Plasmas e Fusão

Nuclear/Laboratório de Aceleradores e Tecnologias de Radiação, Lisbon, Portugal

MANTI Lorenzo - University of Naples Federico II, Naples, Italy

MCCOUSTRA Martin R. S. - Heriot-Watt University, Edimburg, Scotland

SICARD-ROSELLI Cécile - Laboratoire de Chimie Physique, Université de Paris-Sud, Orsay, France

SIMS* Ian, Institut de Physique de Rennes, UMR 625 - Université de Rennes 1, Rennes, France

TOIMIL-MOLARES Maria Eugenia - GSI Helmholtzzentrum für Schwerionenforschung GmbH Materials Research, Darmstadt, Germany

### 4. MEMBERS OF THE ACCELERATOR ADVISORY COMMITTEE (AAC)

Maud Baylac (IN2P3/LPSC)

Romuald Duperrier (DRF/Irfu)

Daniela Kiselev (PSI)

Marco Calviani (CERN)

Nancy Postiau (University Louvain)

Udo Weinrich (GSI/FAIR)
# 5. MEMBERS OF THE SCIENTIFIC COUNCIL

## Mandate 2022-2026

- Amine Cassimi - CIMAP, France

- Anna Corsi - Irfu/DPhN, France

- Anne-Marie Frelin - GANIL, France

- Fabiana Gramegna - LNL INFN, Italy

- Ferid Haddad - ARRONAX, France

- Michal Kowal - NCBJ, Varsovie, Poland

- Alain Letourneau - Irfu/DPhN, France

- Nathalie Moncoffre - IP2IL EMIR&A, France

- Iain Moore - Jyfl, Finland

- Jaromir Mrazek - NPI, Czech Republic

- Christoph Scheidenberger - GSI Darmstadt, Germany

- David Verney - IJCLab France

## Mandate 2019-2023

- Ani Aprahamian - Univ Notre Dame, USA

- Jerome Giovinazzo - CENBG, France

- Rituparna Kanungo - Triumf, Canada

- R.G. Pillay - TIFR Mumbai, India

- Bob Tribble - TAMU, USA

## Ex-officio members:

- Chairperson GANIL PAC

- Chairperson GANIL GUEC

- Chairperson Interdisciplinary PAC

# 6. REPORT OF THE SCIENTIFIC COUNCIL

## INTRODUCTION

The GANIL Scientific Council (SC) met January 17-18, 2023, in a hybrid format. During the first day of the meeting, the SC heard an update detailing on-going activities from Director Patricia Chomaz, which was followed by presentations of possible future initiatives. Attending the meeting for the SC in person were Amine Cassimi, Anna Corsi, Anne-Marie Frelin, Fabiana Gramegna, Férid Haddad, Michal Kowal, Alain Letourneau, Jaromír Mrázek, Nathalie Moncoffre, Iain Moore, David Verney, and Robert Tribble (chair). On-line were Rituparna Kanungo and R.G. Pillay. Also attending was the PAC Chair, Stephan Oberstedt.

The previous SC meeting was held via zoom early in February, 2021, during the height of COVID-19. Much has happened at GANIL during the intervening two years. The progress on commissioning the LINAC in 2021 and then using it for a very successful campaign of research at NFS was a highlight for the facility. Indeed, the success of this campaign is a major step forward toward more routine SPIRAL2 operations. In addition to the work at NFS, the accelerator team produced the first heavy-ion beam in the LINAC in September, 2022. This was another major milestone in the development of SPIRAL2. Today, only NFS is available for SPIRAL2 operations but this will change over the next few years. Next to come on line should be S³. This spectrometer system will be a powerful tool for developing secondary beams of radioisotopes. A report on the commissioning activities associated with S³ was given at the meeting. Detailed comments on the report are included below. Two other major efforts related to SPIRAL2 are also progressing—DESIR and NEWGAIN. The DESIR facility will complement the capabilities of S³ and will greatly expand the program of research on rare isotopes. Both S³ and DESIR will benefit from the higher heavy-ion beam intensities that will be made available from NEWGAIN, which will be optimized to produce beams of A/Q=7 rather than A/Q=3 for the existing injector. With all of these facilities in operation, SPIRAL2 will be able to carry out the world-leading nuclear science program that led to its initiation.
The cyclotrons at GANIL continue to generate new science. The SC notes that they are in high demand by GANIL users. During 2022, cyclotron operations provided new data for several major collaborations. However, problems with unscheduled maintenance limited their overall performance. The cyclotrons now are more than four decades old and are in need of maintenance to reduce lost time due to water leaks inside the vacuum vessels. A plan has been developed—CYREN—to carry out a program of maintenance by replacing resonator cavities. Funding for this work will be crucial to maintain routine operations of the cyclotrons.

Looking ahead, GANIL management is now developing plans to have simultaneous operation of the cyclotrons and the LINAC. This will be very important for the future program as it could provide a path for carrying out science with the LINAC while using cyclotron beams for both science and applications. The GANIL facility is one of the best infrastructures in the EU for carrying out irradiations of electronics for space applications. Today a relatively small amount of time is used for this work. In the future, a larger share of time could be used, but this requires a business plan with a charging scheme that provides the resources for staff to maintain such a broader program, and support for maintenance that would be needed to make a larger amount of beam time available.

At our session on January 18, Director Chomaz gave an overview of the labs future plans, which included a discussion of the report about GANIL's future that was authored by a committee chaired by Professor Michel Spiro. The SC looks forward to continued discussion of GANIL's long term vision and its goals both near and far term at future meetings.

With the change of management and the lapse of two years in SC meetings, some of the recommendations from the 2021 report of the SC were lost. One in particular is sufficiently important that the SC puts it back into this report. In 2021, the recommendation was prompted by the discussion of the workforce needed to carry out simultaneous operation of the LINAC and cyclotrons. As this is an ongoing effort, **the council recommends that a session devoted to workforce concerns and development at all levels, including theory, be included in the next SC meeting.**

Following a discussion of each initiative presented to the SC, a list of recommendations from the 2023 meeting are summarized here:

* The SC recommends that a session devoted to workforce concerns and development at all levels, including theory, be included in the next SC meeting.

* The SC recommends that the collaboration [(NA)2STARS] specify the niche experiments that can be done at the GANIL facility as they develop an MoU with GANIL. It further suggests the addition of GANIL collaborators within the project.

* The SC recommends that an MOU is needed to organize the collaboration [REPARE] among GANIL and medical and biology centers of the Caen region, and to clearly identify commitments of its members. Clear identification of needed investment is mandatory for GANIL and other partners that will take care of the chemistry, radiobiology and radiolabeling as well as preserving the option to move GANIL to SPIRAL2 Phase 2 as recommended in the recent report on GANIL's future.

* The SC notes that it is planned to install this platform [MIRRPLA] in the D2 room of GANIL. This room is currently cluttered and it will be necessary to clear it, make it clean and equip it to receive this new equipment. The workforce and budget requirements on the part of GANIL to allow this installation in D2 seem to be very limited. However, technical adaptations necessary to install MIRRPLA in the D2 room need to be further specified and quantified. The effort from GANIL for the platform installation in the D2 room needs to be estimated.

* The SC recommends to continue the support for the [NEW JEDI] project with respect to the following points:

* The collaboration maintains a reasonably low-medium material/financial demand;

* Workforce (students) requirements that are justified (also in the case of a negative outcome of the analysis);

* The experimental equipment obtained during the project remains in GANIL;
* If a positive result is found for X17, the SC recommends that the [NEW JEDI] collaboration **define the strategy** for the follow-up experiment(s), since GANIL may find itself in a unique position in this potentially new branch of research.

The SC has the following recommendations for S³ commissioning.

* We recommend that GANIL management prioritize a rapid commissioning of the S³ spectrometer.

* We recommend that the S³ scientific collaboration work out a plan for first exploratory physics runs simultaneously while commissioning the spectrometer and the focal plane detectors. The physics cases to be studied during commissioning should evolve through consensus from the collaboration and should be factored into the time allotted for S³ commissioning.

* In particular, physics cases that are easily feasible from already demonstrated beams should be chosen. A list of three possible LEB experiments during commissioning was presented. The physics outcome from each needs to be specifically reviewed for international competitiveness. This was not clearly presented. One experiment each with <sup>40</sup>Ar and <sup>50</sup>Cr beams could be planned. Although the latter is expensive the structure information around <sup>100</sup>Sn will be of high scientific value.

* It was not clear if the possible commissioning experiments with SIRIUS were only to verify published results or if they will also have the potential for some new physics information, too. It is recommended that the collaboration work out a strategy for first experiments. The <sup>22</sup>Ne+Pt -> <sup>216-220</sup>Ra -> <sup>210-214</sup>Ra has a large cross section, hence might be a simpler case to start with if sufficient new physics information can be derived.

* The standalone cryogenic plants and the cryogenic distribution lines need to be fully tested and should be very robust and trouble-free. This aspect needs to be simultaneously ensured, as stable cryogenics is critical for the operation of the spectrometer as a whole and can more often than not, derail the schedule during the commissioning phase.

Below the SC provides reports on the presentations and associated write-ups for (Na)²STARS, REPARE in LHE, MIRPLA, NEW JEDI, and S³ Commissioning.

## (NA)²STARS

The goal of the (NA)2STARS project is the development of a second-generation Total Absorption Spectrometer (TAS), combining efficiency as a calorimeter, segmentation as well as very good energy resolution and timing. The latter characteristics differ from existing spectrometers and will be realized by the addition of (up to 16) LaBr₃ crystals. The project will oversee the upgrade of both DTAS (as originally designed for DESPEC, NUSTAR) as well as Rocinante.

The TAGS technique uniquely addresses limitations in high-resolution gamma-ray spectroscopy by accessing the full beta decay strength within the Q-value window, solving the so-called Pandemonium effect. It is the best method of accessing the beta-decay strength, providing critical constraints on theoretical models of nuclear structure, complementary (and yet more sensitive) to integral observables such as half-lives and P<sub>n</sub> values.

A compelling physics program that can be addressed by the TAS technique is outlined. Regions of nuclear structure interest include <sup>100</sup>Sn, <sup>132</sup>Sn and <sup>78</sup>Ni. For each region, the advantages of the new spectrometer are presented including improved energy resolution, gamma-neutron

resolution, as well as potential gamma-gamma correlations. Nuclear astrophysics plays an important role with relevant beta decays in the mass A~80 region, the r-process region around <sup>132</sup>Sn and <sup>78</sup>Ni, and accurate measurements of the gamma component of the neutron/gamma ratio to constrain neutron capture rates. These regions are also favorable for the study of low-lying collective modes through beta decay. Additional topics include core-collapse supernovae, <sup>44</sup>Ti nucleosynthesis and the origin of p-nuclei. A third main scientific focus relates to neutrino physics and applications with nuclear reactors, including reactor and shape anomalies, as well as the reactor decay heat.
The device can be flexibly used at LISE, S³-LEB, and DESIR, and thus the timetable is adaptable to the expected commissioning of these facilities. Letters of Intent were originally proposed for DESIR, combining the TAS with the Piperade Penning trap to achieve isobaric cleanliness. Possibilities to couple the TAS after the multi-reflection time-of-flight (MR-TOF) mass spectrometer at S³-LEB are encouraging, as well as more immediate implications with the LISE spectrometer. The SC noted that complementary activities are underway at several other facilities, e.g., RIKEN, Jyväskylä, GSI and ISOLDE. Due to a lack of access to neutron-rich nuclei, aspects of the physics program cannot currently be performed at GANIL, and it was not clear from the proposal what the niche experiments would be in the immediate and longer-term.

The proposed instrumentation is discussed regarding the current state-of-the-art worldwide, also noting the potential disadvantage that arises from the large intrinsic radioactive background from the LaBr₃ crystals and how this is mitigated via tagging. It is mandatory to understand the response of the crystals and studies of prototypes have been performed and compared with Monte Carlo simulations. Design studies of the STARS setup based on the DTAS have been started by the Subatech group with GEANT4. The SC would have appreciated additional simulations to illustrate the added advantage of the LaBr3 crystals. This would have afforded an evaluation of whether they bring a major improvement to the capabilities of existing segmented TAS devices, or a more incremental improvement. In connection to this aspect, the SC noted that the granularity of the proposed TAS detectors offers flexibility in the funding timeline for implementing the full 16 crystals. Nevertheless, an opportunity was missed to address the impact on the scientific program with a reduced number of crystals should the project be de-scoped.

The collaboration within (NA)²STARS gathers the leading experts of the TAGS technique in Europe. The IFIC team of Valencia have the expertise to build the detectors and have developed the rigorous analysis codes necessary to extract the requisite data. The IFIC partners will play a critical role at every step of the project. Other partners include CIEMAT Madrid, who have contributed to the analysis methods, have developed tools to address neutron interactions with matter in GEANT4, co-developed and built the MONSTER neutron detector and have general expertise in nuclear instrumentation. IP2I Lyon have expertise in gamma-ray simulations and will oversee the design of STARS with GEANT4 for in-beam cross-section measurements at Neutrons for Science (NFS). The scientific coordinator, Muriel Fallot, is from Subatech. Fallot has been the spokesperson for several TAGS experiments motivated by neutrino physics and Pygmy modes. The Subatech group has excellent visibility as shown by several published articles, and has the expertise needed to analyze and estimate the impact of the TAGS measurements on antineutrino spectra.

The project has a clear management structure, with annexes including details of nine work packages, the institutional breakdown with requisite responsibilities as well as the timeline projected from the various tasks for the upgrade of both DTAS and Rocinante.

## Recommendations and summary

The SC recommends that the collaboration specify the niche experiments that can be done at the GANIL facility as they develop an MoU with GANIL. It further suggests the addition of GANIL collaborators within the project. Given the opportunity to use this device at other facilities to optimize the scientific output, the Council recommend that the GANIL management weigh the options of purchasing the required LaBr3 detectors with asking the partners to explore funding opportunities through national funding agencies and other funding calls, e.g., ANR.

In summary, the SC members are positive towards the (NA)²STARS project.

## REPARE in the LHE

The goal of the project "REPARE in the LHE" is to install a high-power target system for the production of innovative radioelements for targeted alpha therapy (TAT) in the high energy line (LHE) of the SPIRAL2 building. The target system is developed within the REPARE project financed by the French Research Agency ANR, and is planned to be used starting in 2023 to produce ²¹¹At using the alpha beam from SPIRAL2 at NFS. The ANR REPARE is part of a larger project that aims to develop the full chain from the synthesis of ²¹¹At up to clinical trials in