bluuebunny/crossref_metadata_2025 huggingface dataset:
GRAPhEME: Performances, achievements (@EC-JRC/GELINA) and future (@GANIL/SPIRAL2/NFS)
Authors: Kerveno Maëlle , Borcea Catalin , Boromiza Marian , Capote Roberto , Claeys François , Dari Bako Nicolas , De Saint Jean Cyrille , Dessagne Philippe , Drohé Jean Claude , Dupuis Marc , Henning Greg , Hilaire Stéphane , Kawano Toshihiko , Negret Alexandru , Nyman Markus , Olacel Adina , Paradela Carlos , Plompen Arjan , Wynants Ruud
Published: May 2023

GRAPhEME is a γ-spectrometer developed by CNRS/IPHC Strasbourg (France), in collaboration with EC-JRC Geel (Belgium) and IFIN-HH Bucharest (Romania). With its 6 High Purity Planar Germanium detectors and one fission chamber, GRAPhEME, installed at the EC-JRC GELINA facility, was optimized for measurements of accurate (n, xnγ) cross sections on actinides. The experimental methodology is based on the prompt γ-ray spectroscopy coupled to time-of-flight measurements. In this paper, we present an overview of fifteen years of experiments with GRAPhEME at EC-JRC GELINA facility, illustrated by main achievements to highlight the performances reached by our spectrometer. Beyond the experimental work, a close collaboration with theoreticians has emerged allowing the use of the data produced with GRAPhEME to test and constraint nuclear reaction codes like TALYS, CoH and EMPIRE. In a near future, GRAPhEME will be available to start measurement campaigns at the new neutron beam facility SPIRAL2/NFS. There, studies of (n, 2n) and (n, 3n) reactions will be possible and will complete the work done at EC-JRC GELINA on (n, n ) reactions. Despite the amount of cross section data provided by GRAPhEME up to now, the prompt γ-ray spectroscopy method presents some weaknesses that our collaboration tries to overcome. This goes through new calculation schemes based on theoretical modeling constrained on experimental data to infer the total (n, xn) cross section, new instrument to measure conversion electrons but also by being proactive in dissemination activities to make the nuclear structure community aware of our needs about new accurate nuclear structure information on actinides.
Prompt fission neutron spectra in the 235U(n,f) reaction
Authors: Mauss B. , Taïeb J. , Laurent B. , Bélier G. , Chatillon A. , Étasse D. , Morfouace P. , Roig O. , Devlin M. , Gomez J.A. , Haight R. C. , Kelly K. J. , O’Donnell J.M. , Schmitt K.T.
Published: May 2023

Prompt fission neutron spectra (PFNS) are crucial to any neutronic simulation of critical nuclear systems. An experimental setup dedicated to the measurements of PFNS of very high accuracy was developed at the Los Alamos Neutron Science Center (LANSCE) some ten years ago. It allows for the measurement of PFNS for neutron induced fission at the Weapon Neutron Research (WNR) neutron source of the LANSCE. A measurement of the PFNS from the 235U(n,f) reaction was realized recently and is currently analyzed. Preliminary results are presented here and are compared to present nuclear data evaluations.
Thermal Cross Section Measurements At The RPI LINAC
Authors: Fritz Dominik , Danon Yaron , Rapp Michael , Trumbull Timothy , Zerkle Michael , Holmes Jesse , Chapman Chris , Arbanas Goran , Brown Jesse , Ramic Kemal , Hu Xunxiang , Ney Adam , Brain Peter , Singh Sukhjinder , Cook Katelyn , Wang Benjamin
Published: May 2023

Recently, a cold moderator was designed and developed for use at the Rensselaer Polytechnic Institute Linear Accelerator (RPI LINAC). This cold moderator proved to easily and safely couple to an existing neutron producing target, while enhancing neutron flux below 0.02 eV by up to a factor of 8 by cooling polyethylene down to 29 K. This cold moderator capability allowed for significantly improved counting statistics below 0.02 eV not previously possible due to a poor signal to background ratio. Additionally, testing was performed to characterize the energy resolution of the new cold moderator system and found the system easily capable of resolving resonances in Ta-181 at 4 and 10 eV, while also clearly resolving the Bragg edges found in Be metal below 0.01 eV. Following the design and development of a cold polyethylene moderator, a series of thermal total cross section measurements were performed for polyethylene, polystyrene, Plexiglas and yttrium hydride in the thermal region. These measurements serve to help validate thermal scattering law (TSL) evaluations in the 0.0005 – 1 eV energy range. For polyethylene and polystyrene, two sets of experiments were performed – one with the Enhanced Thermal Target (ETT) and another with the ETT plus the new cold moderator capability (ETTC). The yttrium hydride and Plexiglas measurements were only performed with the ETTC. The measurements for polyethylene help to validate the data processing methodology when using the ETTC, while extending the measured range of polyethylene down to 0.0005 eV. Two different Plexiglas, Plexiglas G and Plexiglas G-UVT, and two different concentrations of yttrium hydride, H/Y = 1.85 and 1.68, were measured. Overall, all materials had generally good agreement with their ENDF/B-VIII.0 TSL evaluations, though some discrepancies were noticed. In the case of the yttrium hydride, the high energy oscillations in the hydrogen cross section and the low energy Bragg edges in the yttrium cross section were clearly seen. These measurements represent the first total cross section measurements that encompass the entire thermal region from 0.0005 – 1 eV for polystyrene and yttrium hydride.
Measurements of the Neutron Capture Cross Section of Am-243 with the ANNRI beamline, MLF/J-PARC
Authors: Kodama Yu , Katabuchi Tatsuya , Rovira Gerard , Kimura Atsushi , Nakamura Shoji , Endo Shunsuke , Nakano Hideto , Sato Yaoki , Hori Jun-ichi , Shibahara Yuji , Terada Kazushi
Published: May 2023

The neutron capture cross section of 243Am from thermal to 100 keV was measured using the Accurate Neutron-Nucleus Reaction Measurement Instrument (ANNRI) at the Japan Proton Accelerator Research Complex (J-PARC). The time-of-flight (TOF) method using a NaI(Tl) detector was employed in these measurements and the pulse-height weighting technique was used to derive the neutron capture yield. The preliminary cross section was determined by normalizing the results to JENDL-4.0 cross section data at the third resonance of 243Am. In the thermal energy, the preliminary result is in good agreement with the two latest experimental data measured by the TOF and the activation methods but higher than the evaluated values in JENDL-5.
Nuclide production cross sections in proton-induced reactions on Bi at GeV energies
Authors: Iwamoto Hiroki , Nakano Keita , Meigo Shin-ichiro , Takeshita Hayato , Maekawa Fujio
Published: May 2023

Proton-induced nuclide production cross sections for Bi at incident energies of 0.4, 1.5, and 3.0 GeV are measured with the activation method using the proton beams accelerated from the Rapid-Cycling Synchrotron of the Japan Proton Accelerator Research Complex (J-PARC). A total of 127 cross-section data are obtained. The measured data are compared with two types of Monte Carlo-based spallation models (i.e. INCL++ coupled with ABLA07 and INCL4.6 coupled with GEM), and the evaluated nuclear data library, JENDL/HE-2007. The result showed that INCL++/ABLA07 overall agrees with the experimental data, whereas INCL4.6/GEM underestimates the production of fission fragments.
Measurement of 183W(n, n’γ) and (n, 2nγ) cross-sections (preliminary)
Authors: Henning Greg , Maëlle Kerveno , Dessagne Philippe , Claeys François , Dari Bako Nicolas , Dupuis Marc , Hilaire Stephane , Romain Pascal , de Saint Jean Cyrille , Capote Roberto , Boromiza Marian , Olacel Adina , Negret Alexandru , Borcea Catalin , Plompen Arjan , Paradela Dobarro Carlos , Nyman Markus , Drohé Jean-Claude , Wynants Ruud
Published: May 2023

The necessary improvement of evaluated nuclear databases for appplication will be achieved with improvement of models and new, precise data. In particular, the effect of inelastic neutrons scattering can be of importance for reactors. In order to test the models, we performed measurement of (n, n’γ) and (n, 2nγ) cross-sections on 183W. These data will help constrain the calculation codes and ensure a better evaluation of the total (n, xn) cross section. The experimental setup and the data analysis method will be presented. The preliminary experimental results for the 183W isotope will be compared to predictions from Talys nuclear reaction code.
Comparison of double-differential cross-section between nuclear data library and experimental data for photoneutron production
Authors: Tuyet Tran Kim , Sakaki Yasuhito , Sanami Toshiya , Yamazaki Hiroshi , Namito Yoshihito , Itoga Toshiro , Kirihara Yoichi , Miyamoto Shuji , Asano Yoshihiro
Published: May 2023

In this study, we compared double differential cross-sections (DDXs) between the experimental data obtained by 16.6 MeV of polarized photons and the DDXs from JENDL2004 and JENDL/PD-2016.1 for 197Au, natPb, natCu, and natTi targets. Using Python-based software, we extracted the DDXs from the nuclear data libraries (NDLs), which were subsequently deduced considering the abundances of each target’s isotopes, the width of the photon beam, and the energy resolution of the neutron detectors. For the Ti target, the experimental DDX data were consistent with that of the NDLs. For Pb, Au, and Cu targets, the experimental DDX data at neutron energies higher than 4 MeV were larger than the DDX values obtained from the NDLs. The inconsistency between the DDXs of the experimental data and those of the NDLs indicates the need to improve the physical models to generate the spectrum of photoneutrons.
Total Absorption Spectroscopy of Fission Fragments Relevant for Reactor Physics and Nuclear Structure and Astrophysics
Authors: Estienne Magali , Guadilla V. , Fallot M. , Algora A. , Taín J. L. , Porta A. , Giot L. , Briz J. A. , Bui V. M. , Cormon S. , Jordan D. , Le Meur L. , Rice S. , Valencia E. , Zakari-Issoufou A.-A. , Agramunt J. , Äystö J. , Cucoanes A. , Eronen T. , Fraile L. M. , Ganioglu E. , Gelletly W. , Gorelov D. , Hakala J. , Jokinen A. , Kankainen A. , Kolhinen V. , Koponen J. , Lebois M. , Martinez T. , Monserrate M. , Montaner-Pizá A. , Moore I. , Nácher E. , Orrigo S. E. A. , Penttilä H. , Péru S. , Pohjalainen I. , Reinikainen J. , Reponen M. , Rinta-Antila S. , Rubio B. , Rytkönen K. , Shiba T. , Sonnenschein V. , Sonzogni A. A. , Vedia V. , Voss A. , Wilson J. N.
Published: May 2023

The accurate determination of reactor antineutrino spectra remains a very hot research topic, where new questions have emerged in recent years. Indeed, after the “reactor anomaly” – a deficit of measured antineutrinos at short baseline reactor experiments with respect to spectral predictions – the three international reactor neutrino experiments Double Chooz, Daya Bay and Reno have evidenced spectral distortions in their measurements with respect to the same spectral predictions. This puzzle is called the “shape anomaly”. Recently summation calculations of reactor antineutrino spectra based on the use of nuclear data have obtained the best agreement to date with the reactor neutrino flux measurements at the level of 2% thanks to a decade of Total Absorption Gamma-ray Spectroscopy (TAGS) measurements at the radioactive beam facility of the University of Jyväskylä in two experimental campaigns. A selection of the results obtained so far is presented.
Evolution of collectivity in 126,128Xe studied in Coulomb excitation measurements
Authors: Kisyov Stanimir , Wu Ching-Yen , Henderson Jack , Gade Alexandra , Kaneko Kazunari , Sun Yang , Shimizu Noritaka , Mizusaki Takahiro , Rhodes Daniel , Biswas Sayani , Chester Aaron , Devlin Matthew , Farris Peter , Hill Ava M. , Li Jing , Rubino Elizabeth , Weisshaar Dirk
Published: May 2023

The characteristics of 126,128Xe were investigated in Coulomb excitation measurements performed at the National Superconducting Cyclotron Laboratory (NSCL) Re-accelerator facility, ReA3, Michigan State University (MSU). The Xe nuclei were accelerated to sub-barrier energies and were impinged on 196Pt and 208Pb targets in separate experimental runs. The scattered nuclei and the de-excitation γ-rays were detected using the JANUS setup. Electromagnetic matrix elements were extracted from the experimental data with the help of the GOSIA/GOSIA2 codes. The results were compared to schematic Davydov-Filippov γ-rigid rotor theoretical calculations and large-scale calculations within a newly-established microscopic shell model (called PMMU model). The experimental results agree well with the theoretical predictions, except for the quadrupole moments of the second 2+ states in both nuclei, therefore challenging the interpretation of the γ-bands structure.
On Systematics of Double-Beta Decay Half Lives
Authors: Pritychenko B.
Published: May 2023

Recommended 2β−(2ν) half-lives and their systematics [1, 2] are examined in the framework of a semi-empirical approach. Impacts of nuclear deformation, transition energy, shape coexistence, and forbidden transitions on half-live values were observed. These findings were used to predict T1/2 for 36 isotopes of interest. Current results are compared with available data.
Experimental study of high-energy fission and quasi-fission dynamics with fusion-induced fission reactions at VAMOS++
Authors: Fernández D. , Caamaño M. , Ramos D. , Lemasson A. , Rejmund M. , Álvarez-Pol H. , Audouin L. , Frankland J. D. , Fernández-Domínguez B. , Galiana-Baldó E. , Piot J. , Schmitt C. , Ackermann D. , Biswas S. , Clement E. , Durand D. , Farget F. , Fregeau M. O. , Galaviz D. , Heinz A. , Henriques A. , Jacquot B. , Jurado B. , Kim Y. H. , Morfouace P. , Ralet D. , Roger T. , Teubig P. , Tsekhanovich I.
Published: May 2023

During the last decade, the use of inverse kinematics in the experimental study of fission is bringing a wealth of new observables obtained in single measurements, allowing their analysis and their correlations. An ongoing application of this technique is the basis of a series of experiments performed with the variable-mode, large-acceptance VAMOS++ spectrometer at GANIL. A recent experiment has been focused on the survival of the nuclear structure effects at high excitation energy in fission and quasi-fission. The full isotopic identification of fragments, the fission dynamics and the ratio between the production of fragments with even and odd atomic numbers, the so-called proton even-odd effect, are shown. The latter shows a different mechanism for fission and quasi-fission that could be used to separate fission from quasi-fission.
New Capabilities of the RPI γ-Multiplicity Detector to Measure γ-Production
Authors: Cook Katelyn , Blain Ezekiel , Lewis Amanda , Barry Devin , Rapp Michael , Daskalakis Adam , Brain Peter , Fritz Dominik , Ney Adam , Singh Sukhjinder , Wang Benjamin , Danon Yaron
Published: May 2023

Accurate modeling of γ-production in neutron capture reactions is critical for many applications including on-proliferation, safeguards and modeling nuclear reactors. To improve this work, the Rensselaer Polytechnic Institute (RPI) 16-segment γ-multiplicity NaI(Tl) detector at the Gaerttner Linear Accelerator (LINAC) Center has been upgraded by implementing a digital data acquisition system. The new digitized system records the γ-energy deposition distribution in each individual detector, and γ-multiplicity values as a function of neutron time-of-flight (TOF). With the new capabilities, high precision capture (and fission) yield measurements can be made, and the accuracy of simulation tools used to predict capture γ-cascades can be tested. To validate the updated system, an experiment was performed using a natural Ta sample to measure 181Ta and 180mTa resonance capture yield by detecting prompt γ-rays emitted from neutron capture interactions as a function of both neutron energy and measured γ-multiplicity of each capture event. The results confirm earlier measurements and agree with theoretical yield in the low energy resonance region from 1 to 20 eV. A 238U(n, γ) measurement was also performed to generate γ-spectra. For capture γ-cascades where the total γ-energy deposition is close to the neutron binding energy, γ-spectra were measured for individual resonance energies and observed γ-multiplicities. The results are comparable in shape to a recent measurement done using the Detector for Advanced Neutron Capture Experiments (DANCE) array at Los Alamos Neutron Science Center (LANSCE); however, differences need to be compared to Monte-Carlo n-particle simulations.
140,142Ce Neutron Cross Section Resolved Resonance Region Evaluation
Authors: Chapman Chris W. , Pigni Marco T. , Guber Klaus , Arbanas Goran
Published: May 2023

A resolved resonance region evaluation of 140,142Ce was conducted by Oak Ridge National Laboratory. Requested by the US Nuclear Criticality Safety Program, this evaluation is based on recent high-resolution transmission and capture high-resolution measurements of natCe and 142Ce conducted at JRC-Geel at the Geel Linear Accelerator facility. It is also based on recently measured thermal constants available from the EXFOR database [1]. Starting from the resonance parameters from the ENDF/B-VIII.0 library [2] and following a preliminary R-matrix analysis [3], an updated set of resonance parameters and corresponding covariance information was derived by the fit of these experimental datasets using the Reich–Moore approximation of the R-matrix theory, as implemented in the SAMMY code system [4]. The resolved resonance region upper energy limit for 140Ce was kept at 200 keV, whereas the 142Ce resonance region was extended from 13 to 26 keV. This new evaluation was found to be in good agreement not only with several integral quantities of interest to the reactor physics community, but also with the stellar Maxwellian-averaged cross section [5].
Simultaneous evaluation of uranium and plutonium fast neutron fission cross sections up to 200 MeV for JENDL-5 and its updates
Authors: Otuka Naohiko , Iwamoto Osamu
Published: May 2023

Simultaneous evaluation of 233,235,238U and 239,240,241Pu fission cross sections for fast neutrons up to 200 MeV was performed for the JENDL-5 library. Experimental covariances were estimated for each experimental dataset of cross sections or cross section ratios extracted from the EXFOR library, and they were stored in an experimental database dedicated to the new evaluation. The cross sections were expressed by Schmittroth’s roof functions, and the values on defined incident energy grids were adjusted by the least-squares method to reproduce the experimental cross sections and their ratios. The newly evaluated cross sections were validated using the spectrum averaged cross sections measured in the 252Cf spontaneous fission neutron standard field. The evaluation adopted by the JENDL-5 library was further updated by addition of two datasets and deletion of one dataset.
Measurement of 233U-HU Substitution Reactivity Worth in KUCA for Integral Validation of 233U Nuclear Data
Authors: Sano Tadafumi , Hori Jun-ichi , Takahashi Yoshiyuki , Terada Kazushi , Yashima Hiroshi , Kanda Takashi , Unesaki Hironobu
Published: May 2023

In order to perform an integral evaluation of 233U nuclear data, measurements of substitution reactivity worth between 233U sample and high enriched uranium (HU) sample in the Kyoto University Critical Assembly (KUCA) were carried out. In this study, the experimental core was consisted of 24 fuel elements and 1 special fuel element with the 233U or HU sample. The fuel element was consisted of 31 unit cells and sandwiched by a upper and a lower polyethylene reflector. The unit has one enriched uranium plate of 1/16” thickness, three polyethylene plates of 1/8” thickness. The special fuel element was loaded at the center of the core. The substitution reactivity worth was defined as difference between the excess reactivity of the core in which the 233U sample or the HU sample inserted the core. The excess reactivities ware measured by the positive period method. As the result, the substation reactivity was obtained 0.0146±0.0006 %∆k/k. A numerical result by MVP3 with JENDL-4.0 was 0.0141±0.0002 %∆k/k and a C/E was 0.964 ± 0.041. On the other hand, the calculated substitution reactivity worth with JENDL-5 was 0.0168±0.0002 %∆k/k and a C/E was 1.151±0.047.
Nuclear data activities for medium mass and heavy nuclei at Los Alamos
Authors: Mumpower M. R. , Sprouse T. M. , Kawano T. , Herman M. W. , Lovell A. E. , Misch G. W. , Neudecker D. , Sasaki H. , Stetcu I. , Talou P.
Published: May 2023

Nuclear data is critical for many modern applications from stockpile stewardship to cutting edge scientific research. Central to these pursuits is a robust pipeline for nuclear modeling as well as data assimilation and dissemination. We summarize a small portion of the ongoing nuclear data efforts at Los Alamos for medium mass to heavy nuclei. We begin with an overview of the NEXUS framework and show how one of its modules can be used for model parameter optimization using Bayesian techniques. The mathematical framework affords the combination of different measured data in determining model parameters and their associated correlations. It also has the advantage of being able to quantify outliers in data. We exemplify the power of this procedure by highlighting the recently evaluated 239Pu cross section. We further showcase the success of our tools and pipeline by covering the insight gained from incorporating the latest nuclear modeling and data in astrophysical simulations as part of the Fission In R-process Elements (FIRE) collaboration. We advocate for the adoption of tranmission protocols such as the Unified Reaction Structures for Astrophysics (URSA) for the rapid inclusion of nuclear data into astrophysical simulations.
ACEMAKER: A processing system for producing ACEformatted files for Monte Carlo calculations
Authors: López Aldama Daniel , Trkov Andrej , Capote Roberto , Cullen Dermott E.
Published: May 2023

Since 2016 the Nuclear Data Section of the International Atomic Energy Agency (NDS/IAEA) has encouraged the development of new codes for processing evaluated nuclear data for applications. The main motivation has been the need for improving processing methods and avoiding a common failure mode. The NDS/IAEA has supported the development of the processing system ACEMAKER as a natural extension of the PREPRO family for nuclear data processing with the aim of producing ACE-formatted files for Monte Carlo calculations. The new ACEMAKER modules can process any energy-angle distributions and gamma-production data. The system can generate ACE- formatted files for continuous-energy neutron and photonuclear data, thermal scattering laws and dosimetry cross sections, which can be used for Monte Carlo simulations. The paper summaries the ACEMAKER key features, ongoing verification and validation process, and planned future developments
Development and Verification of Capability for Processing the Generalised Nuclear Database Structure (GNDS) in Nuclear Data Processing Code NECP-Atlas
Authors: Huang Yihan , Zu Tiejun , Cao Liangzhi , Wu Hongchun
Published: May 2023

The latest evaluated nuclear data libraries, including ENDF/B-VIII.0, TENDL2019, all have two formats, the Evaluated Nuclear Data File (ENDF-6) nuclear data format, and the Generalised Nuclear Database Structure (GNDS) format. The first official public documentation of all of the options for storing data in GNDS was released by the Working Party on International Nuclear Data Evaluation Cooperation (WPEC) of the Nuclear Energy Agency. The generalized derived class is designed to be compatible with ENDF-6 and GNDS in nuclear data processing code NECP-Atlas, and the GNDS-Toolkit is developed in NECP-Atlas to parse and convert GNDS. ACE format library and multi-group library are generated based on GNDS, and they are used in the Monte-Carlo code and deterministic based code to compare with ENDF-6. The numerical results show that GNDS libraries can be processed by NECP-Atlas competently to generate specific format library and the difference in ENDF-6 and GNDS is very small.
Assimilation of integral experiments on high-energy nuclear parameters
Authors: Vandermeersch Elias , Tamagno Pierre , De Saint Jean Cyrille
Published: May 2023

Current assimilation of integral experiments often consists in adjusting multi-group cross sections with feedbacks from critical reference benchmarks. In order to maintain the constraints coming from nuclear models, we present here a method to achieve assimilation of integral experiment on nuclear parameters, from which nuclear data are evaluated. This method, based on Bayesian inference, uses continuous energy reactivity sensitivities to nuclear parameters, throughout all the nuclear data types (cross section, angular distribution, energy distribution, fission multiplicity and spectrum). This improvement was made possible by coupling a stochastic transport code and a nuclear data evaluation code. The study of a test case – the assimilation of Jezebel ICSBEP benchmark on a plutonium-239 toy evaluation – shows that angular and energy distributions have a non-negligible impact on the assimilation process and results.
Contributions to Integral Nuclear Data in ICSBEP and IRPhEP since ND 2019
Authors: Bess John , Ivanova Tatiana , Hill Ian , Martin Julie-Fiona , Scott Lori
Published: May 2023

The status of the two neutronics international benchmark projects sanctioned by the Organisation for Economic Co-operation and Development Nuclear Energy Agency (OECD NEA), the International Criticality Safety Benchmark Evaluation Project (ICSBEP) and the International Reactor Physics Experiment Evaluation Project (IRPhEP), was last directly discussed with the international nuclear data community at the 14th International Conference on Nuclear Data for Science and Technology (ND2019) in Beijing, China. Since ND2019, the quantity of available integral benchmark experiment data has increased. The primary purpose of the ICSBEP and IRPhEP is to provide extensively peer-reviewed benchmark data to the international nuclear community in support of validation and testing of nuclear data and models. A total of 28 countries have contributed to the past and continued success of these projects as benchmark evaluations, technical reviews, and experimental data using their own time and resources: 26 to the ICSBEP and 25 to the IRPhEP. Key contributions to the handbooks over the past three years can only be highlighted within this paper. Full technical details and benchmark experiment descriptions can be located within the benchmark reports distributed within recent editions of the handbooks.
Validation of S(α, β) thermal neutron scattering libraries using pulsed-neutron die-away experiments
Authors: Wang Benjamin , Danon Yaron , Blain Ezekiel , Holmes Jesse , Fritz Dominik
Published: May 2023

Validation of the accuracy of S(α, β) thermal scattering law (TSL) evaluations for moderator materials is an important task for the development of high-performance nuclear engineering systems. Many recent thermal neutron scattering evaluations have had limited experimental validation. Like other nuclear data, validation of TSL libraries has historically been by integral criticality benchmarks. While sufficient for general study, these benchmarks often have limited sensitivity to the tested TSLs, and compounding uncertainties from other nuclear data can make validation ambiguous. In some cases, no criticality benchmarks exist that are sensitive to the TSLs of interest. With the development of high-performance next-generation thermal nuclear reactors, alternative validation of applicable TSLs is of high importance. By performing thermal neutron measurements via pulsed-neutron die-away (PNDA) experiments, along with parallel simulations, the integral performance of various TSL evaluations can be compared to measured experimental data. An experimental testbed using a D-T neutron generator, moderator sample, and thermal neutron detector was assembled at Rensselaer Polytechnic Institute. A Thermo Scientific D211 Deuterium-Tritium Neutron generator is used to generate 10 μs neutron pulses. Various targets of different sizes and geometries are used to moderate the neutrons. Multiple detector types and configurations were tested to optimize the experiment. The room-temperature polyethylene TSL evaluation is well vetted and is similar across different evaluations. This makes it an ideal evaluation to compare with the experimental results.
Gestion de la prise en charge d’un frein lingual court du nourrisson à l’enfant
Authors: Demullier Emmanuelle , Deschaseaux Quitterie , Larger Charles
Published: May 2023

Face à l’importance que l’orthodontiste attache à la stabilité de ses traitements, il semble primordial d’étudier toutes les causes de récidives. Cet article expose comment gérer l’ankyloglossie qui entraîne une restriction de la mobilité linguale et peut être considérée comme une cause des troubles des fonctions oro-myo-faciales. Dans cette optique, une étude de la littérature a permis de regrouper les différents points de vue des professionnels de santé qui jouent un rôle essentiel dans cette prise en charge pluridisciplinaire (orthodontiste, ORL, chirurgien maxillo-facial, kinésithérapeute). Les résultats obtenus montrent qu’il n’existe que peu d’études probantes sur le sujet. En découle un manque de recommandations scientifiques concrètes pour une prise en charge efficace de ce trouble.
MIH : mise au point sur les stratégies thérapeutiques pour le meilleur traitement de nos jeunes patients
Authors: Leverd Caroline
Published: May 2023

Décrite pour la première fois en 2001 par Weerjheim, l’hypominéralisation molaire incisive (MIH) est en constante recrudescence, le diagnostic tardif confronte les chirurgiens-dentistes à plusieurs obstacles lors de la prise en charge des enfants atteints de MIH.

Elle représente un véritable défi diagnostic et thérapeutique de par la variabilité déconcertante de ses formes cliniques. Cela nécessite une constante adaptation des solutions thérapeutiques à proposer à nos patients et à leurs parents.

L’évolution de la médecine bucco-dentaire permet d’envisager des traitements efficaces et de proposer des solutions pérennes dans le temps.

Dans ce contexte, il était important de faire le point sur les connaissances actuelles afin d’améliorer le diagnostic et la prise en charge de cette pathologie.
Bereitschaft zur Umsetzung von Präventions- und
Gesundheitsförderungsmaßnahmen für Menschen in
schwierigen Lebenslagen in deprivierten Kommunen in Bayern: Eine qualitative
Analyse
Authors: Steinbeißer Kathrin E. , Wiethaler Maria , Schmid Anna Theresa , Wolff Andrea R.
Published: May 2023

Ziel der Studie Zur Verbesserung der gesundheitlichen Chancengleichheit
ist die Kommune ein zentrales Setting. Für eine bedarfsgerechte und
zielgruppenspezifische Umsetzung von Maßnahmen ist es wichtig, die
Herausforderungen und Bedarfe in den Kommunen zu verstehen. Dies gilt
v. a. für deprivierte Kommunen, die bislang kaum
Gesundheitsförderungsprogramme für Menschen in schwierigen
Lebenslagen anbieten. Die zentrale Forschungsfrage lautet: „Wie wird der
Handlungs- und Unterstützungsbedarf in Bezug auf die Umsetzung von
Maßnahmen der Prävention und Gesundheitsförderung mit
Fokus auf Menschen in schwierigen Lebenslagen in deprivierten Kommunen
wahrgenommen?“

Methodik Mittels leitfadengestützter
Expert/-innenbefragungen (n=10) wurden explorativ qualitative
Daten in fünf bayerischen Kommunen mit hohem Deprivationsgrad erhoben.
Den Grad stellt der Bayerische Index Multipler Deprivation (BIMD, 2010) dar, der
das Ausmaß des Ressourcenmangels auf Gemeindeebene zeigt. Die Daten
wurden mittels inhaltlich strukturierender Inhaltsanalyse nach Kuckartz
analysiert.

Ergebnisse Die entstandenen Hauptthemen der Analyse sind (1) wahrgenommene
Zielgruppen mit Unterstützungsbedarf, (2) Aktivposten für
Prävention und Gesundheitsförderung sowie (3) Handlungsbedarfe
in Bezug auf Prävention und Gesundheitsförderung. In den
befragten Kommunen in Bayern wurden Zielgruppen mit Unterstützungsbedarf
identifiziert. Gleichzeitig zeigte sich, dass in den meisten Kommunen wenige
Ressourcen und Strukturen zur Verfügung stehen, um sich der
Prävention und Gesundheitsförderung mit diesen Zielgruppen
anzunehmen.

Schlussfolgerung Die Studie zeigt, dass deprivierte Kommunen einen Bedarf
an bedarfs- und zielgruppengerechten Maßnahmen der Prävention
und Gesundheitsförderung für Menschen in schwierigen Lebenslagen
aufweisen. Diese Kommunen haben jedoch wenig Handlungsspielräume und
sollten daher gezielt, z. B. durch Vernetzungsarbeit,
unterstützt werden.
Etiopathogenesis behind Semicircular Canal Dehiscence Syndrome: Review Article
Authors:   Surbhi
Published: May 2023

Semicircular canal dehiscence remains one of the rare and least touched chronic vestibular diseases worldwide. Even though microbial, congenital, and genetically determined, as well as mixed characteristics are known to be involved in the pathogenesis of superior semicircular canal dehiscence syndrome (SSCDS), many facets of the pathogenesis of semicircular canal dehiscence syndrome still need to be simplified. Management plan related to pathogenesis has not yet been established. The primary objective of this review is to present and evaluate the etiopathogenesis behind SSCDS. This study is a systematic narrative review. A PubMed search (1970–2022) was performed for studies on epidemiology and pathogenesis of SSCDS. All included articles were categorized according to level of evidence. Five hundred and sixty papers were identified, of which 25 were found to be relevant for this review. SSCDS is a multifactorial disease. There is still no consensus as to what the specific etiology is behind the syndrome. No convincing evidence is available for most associated factors and pathogenesis. Important objectives in research of SSCDS should be achieving consensus about the definition of SSCDS and gaining more in-depth knowledge of the pathogenesis of SSCDS, especially the role of congenital and acquired causes. There is still a need for further well-designed studies on the various etiopathogenesis and management of SSCDS.
Correlation between macroscopic and microscopic relaxation dynamics of water: Evidence for two liquid forms
Authors: Vinh Nguyen Q. , Doan Luan C. , Hoang Ngoc L. H. , Cui Jiarong R. , Sindle Ben
Published: May 2023

Water is vital for life, and without it, biomolecules and cells cannot maintain their structures and functions. The remarkable properties of water originate from its ability to form hydrogen-bonding networks and dynamics, which the connectivity constantly alters because of the orientation rotation of individual water molecules. Experimental investigation of the dynamics of water, however, has proven challenging due to the strong absorption of water at terahertz frequencies. In response, by employing a high-precision terahertz spectrometer, we have measured and characterized the terahertz dielectric response of water from supercooled liquid to near the boiling point to explore the motions. The response reveals dynamic relaxation processes corresponding to the collective orientation, single-molecule rotation, and structural rearrangements resulting from breaking and reforming hydrogen bonds in water. We have observed the direct relationship between the macroscopic and microscopic relaxation dynamics of water, and the results have provided evidence of two liquid forms in water with different transition temperatures and thermal activation energies. The results reported here thus provide an unprecedented opportunity to directly test microscopic computational models of water dynamics.
Theory of mobility of inhomogeneous-polymer-grafted particles
Authors: Tian Xiaofei , Chen Ye , Xu Xiaolei , Xu Wen-Sheng , Chen Jizhong
Published: May 2023

We develop a theory for the motion of a particle grafted with inhomogeneous bead-spring Rouse chains via the generalized Langevin equation (GLE), where individual grafted polymers are allowed to take different bead friction coefficients, spring constants, and chain lengths. An exact solution of the memory kernel K(t) is obtained for the particle in the time (t) domain in the GLE, which depends only on the relaxation of the grafted chains. The t-dependent mean square displacement g(t) of the polymer-grafted particle is then derived as a function of the friction coefficient γ0 of the bare particle and K(t). Our theory offers a direct way to quantify the contributions of the grafted chain relaxation to the mobility of the particle in terms of K(t). This powerful feature enables us to clarify the effect on g(t) of dynamical coupling between the particle and grafted chains, leading to the identification of a relaxation time of fundamental importance in polymer-grafted particles, namely, the particle relaxation time. This timescale quantifies the competition between the contributions of the solvent and grafted chains to the friction of the grafted particle and separates g(t) into the particle- and chain-dominated regimes. The monomer relaxation time and the grafted chain relaxation time further divide the chain-dominated regime of g(t) into subdiffusive and diffusive regimes. Analysis of the asymptotic behaviors of K(t) and g(t) provides a clear physical picture of the mobility of the particle in different dynamical regimes, shedding light on the complex dynamics of polymer-grafted particles.
Observation of anion-stoichiometry phase separation in Fe(Te,Se) film
Authors: Horide Tomoya , Ichinose Ataru , Tanaka Masashi , Matsumoto Kaname
Published: May 2023

Nanostructure control is of fundamental and technological importance because various properties such as vortex pinning in superconductors are determined by the nanostructure. While the nanostructure in superconducting oxides is well controlled, the nanostructure control of iron-based superconductors is required. The nanostructure has not yet been well controlled even in Fe(Te,Se) with the simplest structure among Fe-based superconductors because the anion may be non-stoichiometric and anionic substitution is possible. In this study, we observed the compositional inhomogeneity originating from phase separation in Fe(Te,Se) films, which were prepared by pulsed laser deposition. The films deposited at lower temperature do not show nanoscale compositional inhomogeneity. On the other hand, the high-temperature deposited films contain an inhomogeneous anion distribution with the size of ∼8 nm due to phase separation. The spacing of the compositional inhomogeneity is ∼16 nm. This structure obtained by phase separation is expected to be an effective pinning center in high magnetic fields after further optimization. Thus, the method of nanostructure control other than nanocomposite formation in oxides is demonstrated for Fe(Te,Se).
A health justice partnership for young people: strategies for program promotion to young people and youth workers
Authors: Ollerenshaw Alison , Camilleri Margaret
Published: May 2023

Health justice partnerships (HJP) are innovative models for delivering integrated health and legal services to people experiencing complex issues. An HJP was established in regional Victoria, Australia, for young people. Promoting the program to young people and workers was essential for program uptake. There is a dearth of published information about strategies that support program promotion for young people and workers. In this practice and innovation paper, three promotional strategies were employed: a dedicated program website, secondary consultations, and legal education and information sessions. Each strategy is examined, with information presented about why and how these strategies were implemented alongside this HJP. The strengths and limitations of each strategy are explored, with some strategies appearing to engage audiences with the program more than others. The insights about each of the strategies established for this program may inform other HJPs with their planning and implementation for increased program awareness.
Gradience in iconicity
Authors: Odiegwu Nancy Chiagolum , Romero-Trillo Jesús
Published: May 2023

While it has largely been taken for granted by most linguists that the relationship between linguistic signifier
and signified is arbitrary in nature, a growing number of studies suggest otherwise. In this article, we demonstrate that
iconicity in total reduplicative constructions in Nigerian Pidgin is graded in nature, and that the degree of iconicity of any
given reduplicative is largely correlated with the word class to which its simplex form belongs, with reduplicated ideophones and
adverbials exhibiting the highest degree of iconicity, reduplicated pronouns the lowest degree of iconicity, and reduplicated
adjectives, nouns, numerals and verbs intermediate degrees of iconicity.

Our results shed light, not only on which word classes are more prototypically involved in reduplication than
others in the world’s languages, but also on typical pathways that reduplicatives follow in processes of grammaticalization,
whereby their isomorphic form-meaning relationship appears increasingly attenuated, albeit due to varying language-internal
factors that are specific to individual languages.
Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A ∗
Authors: Vagnozzi Sunny , Roy Rittick , Tsai Yu-Dai , Visinelli Luca , Afrin Misba , Allahyari Alireza , Bambhaniya Parth , Dey Dipanjan , Ghosh Sushant G , Joshi Pankaj S , Jusufi Kimet , Khodadi Mohsen , Walia Rahul Kumar , Övgün Ali , Bambi Cosimo
Published: May 2023

Horizon-scale images of black holes (BHs) and their shadows have opened an unprecedented window onto tests of gravity and fundamental physics in the strong-field regime. We consider a wide range of well-motivated deviations from classical general relativity (GR) BH solutions, and constrain them using the Event Horizon Telescope (EHT) observations of Sagittarius A

∗

(Sgr A

∗

), connecting the size of the bright ring of emission to that of the underlying BH shadow and exploiting high-precision measurements of Sgr A

∗

’s mass-to-distance ratio. The scenarios we consider, and whose fundamental parameters we constrain, include various regular BHs, string-inspired space-times, violations of the no-hair theorem driven by additional fields, alternative theories of gravity, novel fundamental physics frameworks, and BH mimickers including well-motivated wormhole and naked singularity space-times. We demonstrate that the EHT image of Sgr A

∗

places particularly stringent constraints on models predicting a shadow size larger than that of a Schwarzschild BH of a given mass, with the resulting limits in some cases surpassing cosmological ones. Our results are among the first tests of fundamental physics from the shadow of Sgr A

∗

and, while the latter appears to be in excellent agreement with the predictions of GR, we have shown that a number of well-motivated alternative scenarios, including BH mimickers, are far from being ruled out at present.
Recollapsing spacetimes with Λ
<
0
Authors: Fajman David , Kraft Maximilian
Published: May 2023

We show that any homogeneous initial data set with

Λ
<
0

on a product three-manifold of orthogonal form

(

S

1

×
F
,

a
0
2

d

z
2

+

b
0
2

σ
2

,

c
0

d

z
2

+

d
0

σ
)

, where

(
F
,
σ
)

is a closed two-surface of constant curvature and

a
0

,
…
,

d
0

are suitable constants, recollapses under the Einstein-flow with a negative cosmological constant and forms crushing singularities at the big bang and the big crunch, respectively. Towards certain singularities among those the Kretschmann scalar remains bounded. We then show that the presence of a massless scalar field causes the Kretschmann scalar to blow-up towards both ends of spacetime for all solutions in the corresponding class. By standard arguments this recollapsing behaviour extends to an open neighbourhood in the set of initial data sets and is in this sense generic close to the homogeneous regime.
Primordial black holes in loop quantum cosmology: the effect on the threshold
Authors: Papanikolaou Theodoros
Published: May 2023

Primordial black holes form in the early Universe and constitute one of the most viable candidates for dark matter. The study of their formation process requires the determination of a critical energy density perturbation threshold

δ

c

, which in general depends on the underlying gravity theory. Up to now, the majority of analytic and numerical techniques calculate

δ

c

within the framework of general relativity. In this work, using simple physical arguments we estimate semi-analytically the PBH formation threshold within the framework of quantum gravity, working for concreteness within loop quantum cosmology (LQC). In particular, for low mass PBHs formed close to the quantum bounce, we find a reduction in the value of

δ

c

up to

50
%

compared to the general relativistic regime quantifying for the first time to the best of our knowledge how quantum effects can influence PBH formation within a quantum gravity framework. Finally, by varying the Barbero–Immirzi parameter γ of loop quantum gravity (LQG) we show its effect on the value of

δ

c

while using the observational/phenomenological signatures associated to ultra-light PBHs, namely the ones affected by LQG effects, we propose the PBH portal as a novel probe to constrain the potential quantum nature of gravity.
Global high-order numerical schemes for the time evolution of the general relativistic radiation magneto-hydrodynamics equations
Authors: Izquierdo M R , Pareschi L , Miñano B , Massó J , Palenzuela C
Published: May 2023

Modeling correctly the transport of neutrinos is crucial in some astrophysical scenarios such as core-collapse supernovae and binary neutron star mergers. In this paper, we focus on the truncated-moment formalism, considering only the first two moments (M1 scheme) within the grey approximation, which reduces Boltzmann seven-dimensional equation to a system of

3
+
1

equations closely resembling the hydrodynamic ones. Solving the M1 scheme is still mathematically challenging, since it is necessary to model the radiation-matter interaction in regimes where the evolution equations become stiff and behave as an advection-diffusion problem. Here, we present different global, high-order time integration schemes based on Implicit-Explicit Runge-Kutta methods designed to overcome the time-step restriction caused by such behavior while allowing us to use the explicit Runge-Kutta commonly employed for the magneto-hydrodynamics and Einstein equations. Finally, we analyze their performance in several numerical tests.