bluuebunny/crossref_metadata_2025 huggingface dataset:
Do stellar-mass and super-massive black holes have similar dining habits?
Authors: Arcodia R. , Ponti G. , Merloni A. , Nandra K.
Published: June 2020

Over the years, numerous attempts have been made to connect the phenomenology and physics of mass accretion onto stellar-mass and super-massive black holes in a scale-invariant fashion. In this paper, we explore this connection at the radiatively efficient (and non-jetted) end of accretion modes by comparing the relationship between the luminosity of the accretion disc and corona in the two source classes. Motivated by the apparently tight relationship between these two quantities in active galactic nuclei (AGNs), we analyse 458 RXTE-PCA archival observations of the X-ray binary (XRB) GX 339–4, using this object as an exemplar for the properties of XRBs in general. We focus on the soft and soft-intermediate states, which have been suggested to be analogous to radiatively efficient AGNs. The observed scatter in the logLdisc − logLcoronarelationship of GX 339–4 is high (∼0.43 dex) and significantly larger than in a representative sample of radiatively efficient, non- or weakly jetted AGNs (∼0.30 dex). At first glance, this would appear contrary to the hypothesis that the systems simply scale with mass. On the other hand, we also find that GX 339–4 and our AGN sample show different accretion rate and power-law index distributions, with the latter in particular being broader in GX 339–4 (dispersion of ∼0.16 cf. ∼0.08 for AGN). GX 339–4 also shows an overall softer slope, with a mean value of ∼2.20 as opposed to ∼2.07 for the AGN sample. Remarkably, once similarly broad Γ andṁdistributions are selected, the AGN sample overlaps nicely with GX 339–4 observations in the mass-normalised logLdisc − logLcoronaplane, with a scatter of ∼0.30 − 0.33 dex in both cases. This indicates that a mass-scaling of properties might hold after all, with our results being consistent with the disc-corona systems in AGNs and XRBs exhibiting the same physical processes, albeit under different conditions for instance in terms of temperature, optical depth and/or electron energy distribution in the corona, heating-cooling balance, coronal geometry and/or black hole spin.
The CARMENES search for exoplanets around M dwarfs
Authors: Bauer F. F. , Zechmeister M. , Kaminski A. , Rodríguez López C. , Caballero J. A. , Azzaro M. , Stahl O. , Kossakowski D. , Quirrenbach A. , Becerril Jarque S. , Rodríguez E. , Amado P. J. , Seifert W. , Reiners A. , Schäfer S. , Ribas I. , Béjar V. J. S. , Cortés-Contreras M. , Dreizler S. , Hatzes A. , Henning T. , Jeffers S. V. , Kürster M. , Lafarga M. , Montes D. , Morales J. C. , Schmitt J. H. M. M. , Schweitzer A. , Solano E.
Published: June 2020

The high-resolution, dual channel, visible and near-infrared spectrograph CARMENES offers exciting opportunities for stellar and exoplanetary research on M dwarfs. In this work we address the challenge of reaching the highest radial velocity precision possible with a complex, actively cooled, cryogenic instrument, such as the near-infrared channel. We describe the performance of the instrument and the work flow used to derive precise Doppler measurements from the spectra. The capability of both CARMENES channels to detect small exoplanets is demonstrated with the example of the nearby M5.0 V star CD Cet (GJ 1057), around which we announce a super-Earth (4.0 ± 0.4 M⊕) companion on a 2.29 d orbit.
A search for supernova-like optical counterparts to ASKAP-localised fast radio bursts
Authors: Marnoch Lachlan , Ryder Stuart D. , Bannister Keith W. , Bhandari Shivani , Day Cherie K. , Deller Adam T. , Macquart Jean-Pierre , McDermid Richard M. , Xavier Prochaska J. , Qiu Hao , Sadler Elaine M. , Shannon Ryan M. , Tejos Nicolas
Published: June 2020

Fast radio bursts (FRBs) are millisecond-scale radio pulses, which originate in distant galaxies and are produced by unknown sources. The mystery remains partially because of the typical difficulty in localising FRBs to host galaxies. Accurate localisations delivered by the Commensal Real-time ASKAP Fast Transients (CRAFT) survey now provide an opportunity to study the host galaxies and potential transient counterparts of FRBs at a large range of wavelengths. In this work, we investigate whether the first three FRBs accurately localised by CRAFT have supernova-like transient counterparts. We obtained two sets of imaging epochs with the Very Large Telescope for three host galaxies, one soon after the burst detection and one several months later. After subtracting these images no optical counterparts were identified in the associated FRB host galaxies, so we instead place limits on the brightness of any potential optical transients. A Monte Carlo approach, in which supernova light curves were modelled and their base properties randomised, was used to estimate the probability of a supernova associated with each FRB going undetected. We conclude that Type Ia and IIn supernovae are unlikely to accompany every apparently non-repeating FRB.
Computer simulation study about the dependence of amorphous silicon photonic waveguides efficiency on the material quality
Authors: Fantoni Alessandro , Costa João , Lourenço Paulo , Vieira Manuela
Published: June 2020

Amorphous silicon PECVD photonic integrated devices are promising candidates for low cost sensing applications. This manuscript reports a simulation analysis about the impact on the overall efficiency caused by the lithography imperfections in the deposition process. The tolerance to the fabrication defects of a photonic sensor based on surface plasmonic resonance is analysed. The simulations are performed with FDTD and BPM algorithms. The device is a plasmonic interferometer composed by an a-Si:H waveguide covered by a thin gold layer. The sensing analysis is performed by equally splitting the input light into two arms, allowing the sensor to be calibrated by its reference arm. Two different 1 × 2 power splitter configurations are presented: a directional coupler and a multimode interference splitter. The waveguide sidewall roughness is considered as the major negative effect caused by deposition imperfections. The simulation results show that plasmonic effects can be excited in the interferometric waveguide structure, allowing a sensing device with enough sensitivity to support the functioning of a bio sensor for high throughput screening. In addition, the good tolerance to the waveguide wall roughness, points out the PECVD deposition technique as reliable method for the overall sensor system to be produced in a low-cost system. The large area deposition of photonics structures, allowed by the PECVD method, can be explored to design a multiplexed system for analysis of multiple biomarkers to further increase the tolerance to fabrication defects.
Ag nanoparticle-based efficiency enhancement in an inverted organic solar cell
Authors: Salem Dalila , Shalabi Manal , Souissi Fathi , Nemmar Farida , Belkaid Mohammed Said , Aamir Muhammad , Nunzi Jean-Michel
Published: June 2020

Herein, we demonstrate the improvement in performance of inverted organic solar cells fabricated with an Ag-nanoparticle (Np) modified ZnO-electron transport layer. Ag NP incorporation into the ZnO layer increases light harvesting efficiency of the solar device which untimely improves Jsc of the device. As a result, power conversion efficiency (PCE) of ZnO + Ag Np buffer layer based (ITO/ZnO:Ag NP/P3HT: PCBM/MoO3/Ag) device reaches 3.02% which is 27% higher than ITO/ZnO/P3HT: PCBM/MoO3/Ag device and 55.6% higher than the electron transfer layer(ETL) free (ITO/P3HT: PCBM/MoO3/Ag) control device.
Hysteresis and controllability of affine driftless systems: some case studies
Authors: Bagagiolo Fabio , Zoppello Marta
Published: June 2020

We investigate the controllability of some kinds of driftless affine systems where hysteresis effects are taken into account, both in the realization of the control and in the state evolution. In particular we consider two cases: the one when hysteresis is represented by the so-called play operator, and the one when it is represented by a so-called delayed relay. In the first case we prove that, under some hypotheses, whenever the corresponding non-hysteretic system is controllable, then we can also, at least approximately, control the hysteretic one. This is obtained by some suitably constructed approximations for the inputs in the hysteresis operator. In the second case we prove controllability for a generic hysteretic delayed switching system. Finally, we investigate some possible connections between the two cases.
Blood Flow Restriction – Einsatz und Nutzen in der Rehabilitation
Authors: Behrendt Tom , Bielitzki Robert , Schega Lutz
Published: June 2020

Das Primärziel muskuloskelettaler Rehabilitationsmaßnahmen orientiert auf die Wiederherstellung des prätraumatischen Leistungs- und Belastungsniveaus. Besonders infolge von orthopädischen Eingriffen oder nach Verletzungen sollte eine frühzeitige und progressive Rehabilitation erfolgen, um den Genesungsprozess optimal zu unterstützen und die körperliche Leistungsfähigkeit schnellstmöglich wiederherzustellen. In diesem Zusammenhang steht das Blood Flow Restriction-Training als vielversprechende Therapiemaßnahme im Fokus aktueller Forschung. Der vorliegende Übersichtsbeitrag stellt einen Einblick über die Funktionsweise und Wirkungsmechanismen des Blood Flow Restriction-Trainings sowie essenziellen Einsatzmöglichkeiten und Anwendungshinweise für die Praxis bereit.
Die Rolle des Dehnens in der orthopädischen Sport- und Bewegungstherapie
Authors: Schuber André Arik
Published: June 2020

Ist Dehnen im orthopädischen Therapiekontext nützlich und notwendig? Dieser Frage stehen viele Sport- und Bewegungstherapeuten wenn nicht ratlos, dann doch zumindest unsicher gegenüber. In der Tat ist kaum ein anderer Themenbereich der Sportwissenschaft so stark durch pseudowissenschaftliche Aussagen, persönliche Erfahrung und Trainingsmythen geprägt. Der vorliegende Artikel gibt deshalb einen kritischen Überblick über den aktuellen Stand der Dehnungsforschung, arbeitet die verschiedenen Anwendungsfelder heraus und liefert grundlegende Praxisempfehlungen für den Therapiealltag.
Der Semiokklusionsverband – Entwicklung des Vertrauens seitens der Patienten in die Methode während der Behandlung und des Ausmaßes der Geruchsemission
Authors: Ordosch Markus , Maucher Valentin
Published: June 2020

Ziel Die vorliegende Studie untersucht, wie sich während der Behandlung einer Weichteildefektverletzung an einem Fingerendglied das Vertrauen der Patienten in die Behandlung mit einem Semiokklusionsverband, aber auch die Geruchsbelästigung entwickelt.

Patienten und Methoden 17 Patienten mit einer Fingerkuppenamputationsverletzung wurden mit einem Semiokklusionsverband behandelt. Bei jedem Verbandswechsel wurden sie bzgl. ihres Vertrauens in die Behandlungsmethode als auch bzgl. der vorhandenen Geruchsbelästigung befragt, wobei beides mittels numerischer Analogskala mit 0 = kein Vertrauen resp. keine Geruchsbelästigung und 10 = absolutes Vertrauen resp. größte Geruchsbelästigung erfasst wurde. Nach Abheilen der Verletzung wurde die Dicke der regenerierten Fingerbeere sonographisch gemessen und mit der des unverletzten Fingers der Gegenseite verglichen.

Ergebnisse Bereits zu Beginn der Behandlung war das Vertrauen in die Behandlungsmethode hoch (8,5 ± SD 1,1). Die Geruchsbelästigung erreichte beim 3. Verbandswechsel ihren Höhepunkt mit 5,6 ± SD 2,5. Parallel zur abnehmenden Geruchsbelästigung kam es zwischen dem 3. und 4. Verbandswechsel zum höchsten Anstieg des Vertrauens in die Behandlung. Sonographisch wurde die Dicke der Fingerbeere am verletzten Finger nach Abheilen des Defektes mit 3,0 ± 0,6 mm bestimmt, auf der unverletzten Gegenseite mit 3,4 ± 0,8 mm.

Schlussfolgerung Das Vertrauen, dass eine Fingerkuppendefektverletzung bei Behandlung mit einem Semiokklusionsverband vollständig abheilt, ist von Beginn an groß. Mit Rückgang der Geruchsbelästigung steigt sie weiter an.
Pediatric Non–Brain Stem High-Grade Glioma: A Single-Center Experience
Authors: Alimohammadi Ehsan , Bagheri Seyed Reza , Delfani Nasrin , Safari-Faramani Roya , Janatolmakan Maryam
Published: June 2020

Background Pediatric high-grade gliomas (PHGGs) consist of a heterogeneous class of central nervous system (CNS) neoplasms with a poor prognosis. We aimed to present our 10-year experience in the management of children with high-grade glioma focusing on patients’ survival and related factors.

Methods All pediatric patients with high- grade glioma (HGG) who were admitted to our center between May 2009 and May 2018 were investigated. Overall survival (OS) was calculated from the time of diagnosis until the day of death. The impact of suggested variables on survival was evaluated using the univariate and multivariate analyses.

Results There were 41 children with non–brain stem high-grade glioma (NBSHGG). The mean OS of patients was 21.24 ± 10.16 months. The extent of resection (p = 0.002, hazard ratio [HR] = 4.84), the grade of the tumor (p = 0.017, HR = 4.36), and temozolomide (TMZ) therapy (p = 0.038, HR = 3.57) were the independent predictors of OS in children with NBSHGG. Age, gender, tumor location, and size of tumor were not associated with the survival of these patients.

Conclusion HGGs are uncommon pediatric tumors with an aggressive nature and a poor prognosis. Our results revealed that in NBSHGG cases, children with maximal safe tumor resection and children that received temozolomide therapy as well as children with grade III of the tumor had higher survival.
Peak Alpha Frequency in Relation to Cognitive Performance
Authors: Rathee Sushma , Bhatia Divya , Punia Vikas , Singh Rajbir
Published: June 2020

Objective  Peak alpha frequency (PAF) is reported to be a nervous system property which is genetically endowed and reflected in individual’s cognitive functioning. Cognitive performance denotes the mental processes for effective changes in response to situations in general and mental task in particular. None of the study has till now used reading comprehension as a measure of cognitive functioning, which is considered to be a measure of higher cognitive processes. The reading comprehension task used in the study implies certain cognitive processes such as reading ability, comprehension, memory performance involving information maintenance, and retrieval. Therefore, the study was conducted to test the hypothesis of differences in cognitive reading comprehension performance between high- and low-peak alpha subjects.

Materials and Methods A group of 300 healthy participants were selected on the basis of incidental-cum-probabilistic sampling from seven districts of Indian state of Haryana. In the present study, reading comprehension task (Hindi–English; bilingual format) was used to assess the cognitive performance and multichannel electroencephalography alpha frequencies were recorded to measure PAF through power spectrum density analysis of each subject.

Results The findings revealed that individuals with high-peak alpha frequency had significantly higher score (p < 0.05) on reading comprehension task as compared with individuals with low PAF.

Conclusion The present study concluded that the reading comprehension task is effected by peak alpha frequency of an individual. PAF can be considered to be a correlate of cognitive performance.
Isolated Arthroscopic Radial Styloidectomy: The Three-Portal Approach
Authors: Herzberg Guillaume , Burnier Marion
Published: June 2020

Background The current gold-standard technique for radial styloidectomy is arthroscopic. The use of only two dorsal portals may not allow a crystal-clear view of the dorsal arthritic rim of the radius because of the dorsal capsule synovitis.

Objectives To propose a new technique for isolated arthroscopic radial styloidectomy. The addition of a volar radial portal and a sequential procedure are presented.

Patients and Methods Two trochars for alternatively viewing from volar radial or 3–4 are used. A 1–2 portal is used for instrumentation with a motorized burr. We have been using the three-portal technique in 34 cases (26 isolated).

Results This modification of the classic arthroscopic radial styloidectomy is technically easy and the view of the dorsal rim of the radius provides a clear definition and treatment of the dorso-radial arthritic pathology.

Conclusions The authors recommend this technical trick to perform an easy and comprehensive isolated palliative or curative arthroscopic radial styloidectomy.
Reaction of dication C++ with molecular hydrogen at temperature 20 K
Authors: Plašil R , Kovalenko A , Tran T D , Rednyk S , Dohnal P , Roučka Š , Glosík J
Published: June 2020

Synopsis

The reaction of dication C++ with H2 was studied at temperature 20 K using a linear 22-pole radiofrequency ion trap. The overall reaction rate coefficient was measured as 1.4 ± 0.3 × 10−10 cm3 s−1. The upper limit for formation of CH+ in this reaction was evaluated as 4 × 10−12 cm3 s−1.
Chiral Bloch oscillations of a biased bosonic ladder in an artificial gauge field
Authors: Qiao X , Zhang X B , Zhang A X , Yu Z F , Xue J K
Published: June 2020

Synopsis

Rich chiral Bloch oscillations are predicted to distinguish the Meissner phase, Vortex phase and two new Plane Wave phases of the biased non-interacting bosonic ladder in an artificial gauge field.
Design and simulation of a novel magneto-optic trap
Authors: Mootheril D M , Kurz N , Mezinska S , Pfeifer T , Dorn A
Published: June 2020

Synopsis

In order to study ultracold gases by photoionization within a Reaction Microscope (ReMi), we investigate a new magneto-optical trap (MOT) configuration for cooling and trapping the atoms. Here we present the simulation results. In comparison with the conventional MOT, the new MOT has four laser beam axes. Two radial laser beam axes along x and y directions and two laser beam axes inclined ± 450 to the MOT/Feshbach coil axis (z axis).
Entropic uncertainty as a predictor of avoided crossing for confined system
Authors: Saha S , Jose J , Deshmukh P C
Published: June 2020

Synopsis

Avoided Crossings are one of the unique spectroscopic features of confined atomic system. Shannon’s information entropy as a predictor of these phenomena by varying the perturbation (confinement strength) on ground state and some of excited states of H atom is studied in this work. In addition to the energy level repulsion at avoided crossing, it is observed that Shannon’s entropy also assures the exchange of information of involved states, and also validates entopic uncertainty.
Observation of indirect ionization of W7+ in EBIT plasma
Authors: Lu Q , He J , Tian H , Li M , Yang Y , Yao K , Chen C , Xiao J , Li J G , Tu B , Zou Y
Published: June 2020

Synopsis

In this work, visible and EUV spectra of W7+ have been measured using the high-temperature super-conducting electron-beam ion trap at the Shanghai EBIT laboratory under extremely low-energy conditions. The relevant atomic structure has been calculated by using the flexible atomic code package and the GRASP2K code. A hypothesis for the charge-state evolution of W7+ is proposed based on our results. The occurrence of W7+ ions results from indirect ionization caused by stepwise excitation between some metastable states of lower-charge-state W ions, at the nominal electron beam energy of 59 eV.
A new F-wave resonant state in the e+-He+ system
Authors: Yan Z-C , Ho Y K
Published: June 2020

Synopsis

Using the complex scaling method, together with employing highly correlated Hylleraas wave functions in which all the interparticle coordinates are included, we have calculated for the first time a F-wave resonance state in the positron-helium positive ion system near the postronium (ground state) formation threshold.
Theoretical studies of energy spectra and E1 transitions of Ni II ion
Authors: Rynkun P , Gaigalas G , Jönsson P
Published: June 2020

Synopsis

Accurate atomic data of the iron group elements are of major importance in astrophysics. In the present work energy spectrum calculations are performed for 332 lowest states for Ni II ion. Energy levels are compared with NIST database recommended values. All computations were done using the general-purpose relativistic atomic structure package GRASP2018.
Generalized oscillator strengths of the valence-shell excitations of sulphur dioxide studied by fast electron impact
Authors: Du X -J , Xu Y -C , Liu Y -W , Zhu L -F
Published: June 2020

Synopsis

Generalized oscillator strengths (GOSs) of the valence-shell excitation of sulphur dioxide are of great importance for modeling the planet’s atmospheric phenomena and astronomical observations, which are determined at an incident electron energy of 1.5keV in this work. The present GOSs are helpful to assign the experimental spectra and explore excitation dynamics.
Rayleigh scattering formalism for the tune-out wavelength: Application to the 2 3
S state of helium
Authors: Drake G W F , Manalo J G , Zhang P-P , Henson B M , Baldwin K G H
Published: June 2020

Synopsis

The tune-out wavelength for an atom interacting with an incident laser beam is reformulated as a zero in the Rayleigh scattering cross section instead of the dynamic polarizability (or AC Stark shift). The two pictures are equivalent in lowest order, but not when higher-order retardation effects are taken into account. Detailed high-precision calculations in Hylleraas coordinates will be presented for the tune-out wavelength of helium at 413 nm near the 2 3
S – 33 P optical transition, including D-wave retardation corrections, and compared with recent high-precision measurements.
B-spline basis implementation of the Hartree-Fock method for arbitrary central potentials
Authors: Waide D T , Green D G , Gribakin G F
Published: June 2020

Synopsis

The Hartree-Fock equations are solved using B-splines. Convergence of self-consistency iterations is achieved by turning on the electron interaction gradually. We test the ground and excited-state sets for atoms and an electron gas confined in a harmonic potential and the jellium model of alkali-metal clusters. Comparisons are made with the Thomas-Fermi approximation and dipole polarizabilities are found and compared with experiment.
Relativistic configuration interaction with core polarization method for the divalent systems
Authors: Wang X , Jiang J , Wu Z W , Xie L Y , Zhang D H , Dong C Z
Published: June 2020

Synopsis

The relativistic configuration interaction with core polarization method and program for the divalent systems have been developed. Based on this new program, the energy levels, transition matrix elements, static and dynamic dipole polarizabilities of He, Be, and Mg atoms have been calculated systematically.
Molecular-frame angular distributions of spectator resonant interatomic coulombic decay electrons in neon dimers
Authors: Mhamdi A , Rist J , Aslitürk D , Weller M , Melzer N , Trabert D , Kircher M , Vela-Pérez I , Siebert J , Eckart S , Grundmann S , Kastirke G , Waitz M , Khan A , Schöffler M S , Trinter F , Dörner R , Jahnke T , Demekhin Ph V
Published: June 2020

Synopsis

The spectator resonant interatomic Coulombic decay (SRICD) following the 2s →5p excitation of Ne dimers has been examined experimentally and theoretically. The molecular frame angular distributions (MFADs) of the SRICD electrons depend strongly on the direction of the polarization vector of the exciting photon with respect to the molecular axis. We demonstrate that this effect is caused by the scattering of the low-energy SRICD electron on the density of the spectator electron.
Bidimensional Sturmian basis for bound states and collision problems
Authors: Randazzo J M , Ancarani L U
Published: June 2020

Synopsis

We present a novel spectral approach to deal both with bound states and with stationary continuum waves associated to collision problems. It is based on the definition of a two dimensional radial basis which replaces the combination of single particle basis sets as employed in most of the usual spectral methods. The new basis elements are externally defined as solutions of a generalized Sturmian eigenvalue equation containing the main properties of the physical problem under consideration.
On unified contribution of pair Coulomb excitations in three-body reactions
Authors: Levin S , Budylin A , Koptelov Y
Published: June 2020

Synopsis

In the present work we obtain the unified contribution of pair excited states to the asymptotics (at infinity in configuration space) of the three-body absolutely continuous spectrum eigenfunctions. Note that it is the case that is most interesting and rich from the physical point of view, as it is connected in particular with re-clustering of charged quantum complexes.
Electron-impact excitation of forbidden and allowed transitions in Cr II
Authors: Tayal S S , Zatsarinny O
Published: June 2020

Synopsis

The B-spline R-matrix method is used to investigate the electron-impact excitation of Cr II. The close-coupling expansion contains 512 fine-structure levels of Cr II and includes all levels of the 3d5, 3d44s, 3d34s2, 3d44p and 3d34s4p configurations. The present results considerably expand the existing data sets for Cr II, allowing a more detailed treatment of the available measured spectra from different space observatories.
Electron impact excitation of the 4 1S0-4
1P1
state of Zn atom
Authors: Xie L Y , Cheng X S , Zhang D H , Jiang J , Wu Z W , Dong C Z
Published: June 2020

Synopsis

The electron impact excitation total and differential cross sections, Stokes parameters, and coherence pa-rameters of Zn atom from the ground state 41S0 to the excited state 41P1 were systematically calculated using the fully relativistic distorted wave method. The calculated results are compared with the experimental data and other theoretical results, good agreement is obtained.
Post-collision interaction in sequential double-ionization of helium
Authors: Artemyev A N , Streltsov A I , Demekhin Ph V
Published: June 2020

Synopsis

We investigate the post-collision interaction between a slow electron released by a pump pulse from the neutral helium atom and a fast electron released by a time-delayed probe pulse from the created ion. To this end, we numerically solve the time-dependent Schrödinger equation in the basis of the essential eigenstates of the unperturbed Hamiltonian. We demonstrate that the energy exchange between the slow and the fast electrons and the recapture of slow photoelectrons can be controlled by the properties of the pulse-sequence.
Spectroscopy and photoionization of C+ ions by the relativistic eigenchannel R-matrix method
Authors: Yue X F , Jin R , Feng H R , Jiao M C , Gao X , Li J M
Published: June 2020

Synopsis

The scattering matrices of C+ are calculated by using our relativistic eigenchannel R-matrix method. With the merits of the analytical continuation properties of the scattering matrices, lots of atomic dynamical data with accuracy are obtained. Much physical quantities are acquired by applying the multichannel quantum defect theory (MQDT) procedure. The present calculated results are in good agreement with the available experimental data, which has been shown by the newly proposed projected high dimensional quantum defect graph (symmetrized), namely JHANGZ plot.
Experimental and theoretical study of singly ionizing 1-MeV p+He collisions at different energy and momentum transfer values
Authors: Chuluunbaatar O , Kouzakov K A , Zaytsev S A , Zaytsev A S , Shablov V L , Popov Yu V , Gassert H , Waitz M , Kim H-K , Bauer T , Laucke A , Müller Ch , Voigtsberger J , Weller M , Rist J , Pahl K , Honig M , Pitzer M , Zeller S , Jahnke T , Ph L , Schmidt H , Schmidt-Böcking H , Dörner R , Schöffler M S
Published: June 2020

Synopsis

We present ultra-high-resolution COLTRIMS data on single ionization of helium induced by 1 MeV proton impact and compare it with theoretical calculations. Our analysis clearly shows the limitations of the first Born approximation.
General formula of shakeup and shakeoff probabilities for arbitrary shells
Authors: Mukoyama T
Published: June 2020

Synopsis

General expressions for the shakeup and shakeoff probabilities following sudden change in central potential have been obtained for arbitrary atomic shells by the use of nonrelativistic hydrogenic wave functions. The final formulae are given in terms of Gauss-type hypergeometric functions. The obtained results are used to calculate the shakeup and shakeoff probabilities for outer-shell electrons following β−decay.
Robust transverse structures in rescattered photoelectron wavepackets and their consequences
Authors: Bredtmann T , Patchkovskii S
Published: June 2020

Synopsis

Initial-state symmetry has been under-appreciated in strong-field spectroscopies, where laser fields dominate the dynamics. We demonstrate numerically that the transverse photoelectron phase structure, arising from the initial-state symmetry, is robust in strong-field rescattering, and has pronounced effects on strong-field photoelectron spectra. Interpretation of rescattering experiments need to take these symmetry effects into account. In turn, robust transverse photoelectron phase structures may enable attosecond sub-Ångström super-resolution imaging with structured electron beams.
Proton scattering from ground and excited states of atomic hydrogen
Authors: Abdurakhmanov I B , Erkilic O , Alladustov Sh U. , Kadyrov A S , Bray I
Published: June 2020

Synopsis

The semiclassical two-centre convergent close-coupling approach is applied to study total ionisation, Balmer emission as well as various excitation and electron-capture transitions in proton collisions with the ground and n = 2 states of atomic hydrogen, where n is the principal quantum number. The results for polarisation fraction of the Balmer-α emission induced in p-H(1s) collisions are in good agreement with experiment at intermediate energies, but surprisingly not at higher energies.
Fully differential study of ionization of H2 by p impact near velocity matching
Authors: Dhital M , Bastola S , Silvus A , Hasan A , Lamichhane B R , Ali E , Ciappina M F , Lomsadze R A , Cikota D , Boggs B , Madison D H , Schulz M
Published: June 2020

Synopsis

Fully differential cross sections (FDCS) for ionization in p + H2 collisions in the region of the electron-projectile velocity matching were measured and calculated. The FDCS were found to be very sensitive to the details of the few-body dynamics underlying the reaction.
A look into the photoionization of medium-sized molecular systems from an XCHEM perspective
Authors: Fernández-Milán P , Klinker M , González-Vázquez J , Martín F
Published: June 2020

Synopsis

In recent years, the XCHEM methodology has been successfully applied to describe photoionization of many-electron atoms and diatomic molecules. In this communication we present the first application of XCHEM to describe photoionization of medium-sized halomethanes and pyrazine.
N-NO & NN-O bond cleavage dynamics in the N2O2+
Authors: Gope K , Luzon I , Strasser D
Published: June 2020

Synopsis

N2O Coulomb explosion is initiated by single-photon double ionization with an ultrafast EUV pulse and is probed by delayed near-IR pulses. The competing two- and three-body dissociation dynamics are reflected in the time resolved branching ratios and in the three-body momentum correlation spectra. Channel resolved kinetic energy release spectra exhibit up to a 0.9 eV shift as a function of time delay – interpreted in terms of the long-bond distance difference between the potentials of a Rydberg ion state and its dication core.
Photoionization of H2 using the molecular R-matrix with time approach
Authors: Benda J , Mašin Z , Armstrong G S J , Clarke D D A , Brown A C , Gorfinkiel J D , van der Hart H
Published: June 2020

Synopsis

We present results of the first calculations using the variational ab initio molecular R-matrix with time approach. We have calculated two and four-photon ionization cross sections for H2 and studied the effects of electron correlation and choice of the Gaussian atomic basis sets. Our results are compared with earlier calculations.
Electron impact ionization of pyrimidine: differential and total cross sections
Authors: Mouawad L , Hervieuxt P-A , Dal Cappello C , Pansanel J , Robert V , El Bitar Z
Published: June 2020

Synopsis

We provide theoretical cross sections for the ionization of pyrimidine by electron impact. The theoretical framework is based on a quantum approach making use of particular tools to overcome the computing challenges. The developed methodology allows to determine not only the total but also the triple, double and simple differential cross sections. This approach was previously used to calculate the triple differential cross sections of many molecules. Here, we demonstrate that it can be used to calculate more integrated cross sections of a molecule of biological interest: pyrimidine.
A quantum approach to calculate differential and total cross sections for electron impact ionization of molecular targets
Authors: Mouawad L , Hervieux P-A , Dal Cappello C , Pansanel J , Robert V , El Bitar Z
Published: June 2020

Synopsis

We present a theoretical approach to calculate the cross sections for the ionization of molecules by single electron impact. It is based on the First Born approximation (FBA), describing the ejected electron by a distorted wave (DW). The cross sections are calculated for an average molecular orientation with the proper average method. Single-center molecular wave functions are generated using Gaussian making this method easily applicable to any molecule. We show the calculated cross sections of some molecular targets of varying complexity.
Channel-resolved molecular Auger spectroscopy
Authors: Ablikim U , Forbes R , Bomme C , Osipov T , Xiong H , Bilodeau R , Kilcoyne D , Rudenko A , Holland D M P , Berrah N , Rolles D
Published: June 2020

Synopsis

Molecular Auger spectra typically consist of many overlapping lines that are hard or impossible to resolve experimentally even with highest-resolution electron spectroscopy techniques. Since molecular Auger energies depend on non-adibatatic dynamics, they can also be difficult to calculate precisely, such that the assignment of molecular Auger transitions is often ambiguous. Here we show that by measuring Auger-electron multi-ion coincidences, we can disentangle the spectra into the contributions from specific ionic final states, which helps significantly with their interpretation and assignment.
Fitting continuum wave functions with complex Gaussians
Authors: Ammar A , Leclerc A , Ancarani L U
Published: June 2020

Synopsis

One particle atomic and molecular bound functions can be easily fitted with a set of real Gaussian type orbitals (r-GTOs). Here we explore how continuum wave functions such as Bessel, Coulomb or generalized Sturmian functions can be represented by a set of real or complex Gaussian type orbitals (c-GTOs) that can, ultimately, enter a molecular scattering calculation.
Geometrically reconstructing laser Coulomb-exploded molecules
Authors: Singh M D , Ramadhan A , Tian K , Sanderson J , Wales B , Karimi R , Beaulieu S , Liu W K , Kieffer J C , Légaré F
Published: June 2020

Synopsis

Geometrical reconstructions are performed for Carbonyl Sulfide (OCS) through Coulomb Explosion Imaging (CEI) employing intense femtosecond laser ionization with pulse durations 7 fs, 30 fs, 60 fs, 100 fs, and 200 fs, using two methods that significantly differ in approach. Firstly, a look up table is employed to reconstruct OCS (2, 2, 2) channel and highlight the presence of degenerate regions. Following this a more sophisticated constrained nonlinear optimization approach improves on precision and gives an indication of uncertainty. Results are compared with equilibrium geometry.
Triple Differential Cross Sections for electron impact ionization of methane at intermediate energy
Authors: Granados C , Ali E , Sakaamini A , Harvey M , Ancarani L U , Murray A J , Dogan M , Ning C , Colgan J , Madison D
Published: June 2020

Synopsis

In a joint experimental and theoretical collaboration, triple differential cross sections are presented for electron-impact single ionization of the 1t2
and 2a1
states of CH4 at an incident electron energy of 250 eV. Experimental data from two different laboratories are compared with molecular 3-body distorted wave (M3DW) and generalized Sturmian function (GSF) calculations. Overall, we find a good experiment-experiment, and also a relatively good experiment-theories, agreement. We observe that for the 1t2
state, similarly to ionization of atomic p-states, the peak is sometimes doubled.
New structures in fully differential cross sections for ionization of He by proton impact
Authors: Dhital M , Bastola S , Silvus A , Hasan A , Lamichhane B R , Ali E , Ciappina M F , Lomsadze R A , Madison D H , Schulz M
Published: June 2020

Synopsis

Fully differential cross sections (FDCS) for ionization in p + He collisions were measured and calcu-lated for several projectile energy losses. The electron angular dependence of the FDCS reveals structures not seen in previous studies.
Photoionization of water: influence of the initial state representations
Authors: Martini L , Boll Dir , Fojon O A
Published: June 2020

Synopsis

We study theoretically the photoionization of water molecules by monochromatic linearly polar-ized photons. We elaborated a model in which the final state wavefunctions are given by Coulomb continuum wavefunctions with distorted charges and the bound states are represented by using different wavefunctions. We contrast our calculations for photon energies between 20 and 300 eV with more elaborated theories and experimental results. We achieve a very good agreement with experiments, especially at enough high energies where elaborated results are not available.
Development of pulse selectors for the synchrotron radiation pulses from the Photon Factory 2.5 GeV ring to study multiple photoionization
Authors: Adachi J , Tanaka H , Kosuge T , Ishii H , Suzuki I H , Kaneyasu T , Taniguchi T , Odagiri T , Ohtaki S , Tsuji Y , Soejima K , Lablanquie P , Hikosaka Y
Published: June 2020

Synopsis

We have developed three pulse selectors to obtain soft x-ray pulses with repetition rates suitable for electron coincidence measurements. The devices enable us to pick out the light pulse from the solo bunch located in the center of the 364-ns dark gap of the hybrid-filling operation. We report the development status and show some typical results of the coincidence measurements with the pulse selectors.
Electron emission from fluorene molecule in collisions with 3.5 MeV/u Si8+ ions
Authors: Bagdia C , Roychowdhury M , Mandal A , Champion C , Tribedi L C
Published: June 2020

Synopsis

We present measured absolute double differential cross section (DDCS) of electron emission from fluorene (C13H10) molecule upon 3.5 MeV/u Si8+ ion impact. We have compared the energy and angular distributions of the DDCS with CB1 (Ist Born with correct boundary conditions) calculations. The e-DDCS shows an indication of collective excitation peak in low energy part of the spectrum at a few backward angles. The shape of the distribution has also been compared with that for a smaller molecule i.e. CH4.
Photoionization microscopy: linear polarization rotation effects
Authors: Kalaitzis P , Danakas S , Lépine F , Bordas C , Cohen S
Published: June 2020

Synopsis

Photoionization microscopy (PM) aims at imaging the flux of slow (meV) electrons released by atomic photoionization in the presence of a static electric field. We discuss the rotation of the linear light polari-zation with respect to the electric field direction. Two-photon ionization out of an m=0 initial state allows for the population of |m|=0,1,2 Stark states. The resulting |m|-beating effects in the PM images are demonstrated theoretically (in hydrogen atom) and experimentally (in Mg atom). Implications on the applicability of tomographic techniques for slow electrons are also discussed.
Cross section scaling for the ionization of H2O by highly charged ions
Authors: Bachi N , Otranto S , Olson R E
Published: June 2020

Synopsis

A classical trajectory Monte Carlo model that explicitly considers the ten electrons of the H2O molecule is used to study electron production in collisions involving bare ions. Present results are contrasted to the reported experimental data and to other theoretical results obtained by means of distorted wave models. Focus is made on the energy range 100 (keV/amu)/ZP-1000 (keV/amu)/ZP along which a simple scaling for the net cross section is introduced.
Electron correlation in simultaneous electron transfer and excitation: results of new 2eAOCC calculations and comparison to experiment in 50-500 keV He+ + H/H2 collisions
Authors: Dubois A , Zouros T J M
Published: June 2020

Synopsis

New two-electron semiclassical atomic orbital coupled channel calculations (2eAOCC) are compared to experiment and to older coupled channel calculations. Progress in these type of calculations is assessed in an effort to investigate the effect of electron correlations in this fundamental collision system.
Electron capture by low velocity highly charged ions A tribute to Michel Barat
Authors: Roncin P , Guillemot L
Published: June 2020

Synopsis

Michel Barat passed away last November at the age of 80. We briefly review the contributions under his supervision where we revisited atomic collisions in the blooming context of highly charged ions.
Dissociative Electron Attachment to MgCN
Authors: Orel A , Larson Å
Published: June 2020

Synopsis

Dissociative electron attachment (DEA) to the molecule MgCN and its isomer MgNC have been proposed as possible sources of CN− in the interstellar media. We have carried out electron scattering calculations using the Complex Kohn Variational Method as a function of the internal degrees of freedom to obtain the resonance energy surfaces and autoionization widths. We use this data as input to form the Hamiltonian relevant to the nuclear dynamics. The multidimensional wave equation is solved using the MultiConfiguration Time-Dependent Hartree (MCTDH) approach. We compute the DEA cross sections.
Low-energy electron scattering from methylene radicals: multichannel-coupling effects
Authors: Wang K D , Zhang H X
Published: June 2020

Synopsis

We reported elastic and excitation cross sections for electron collisions with methylene radical using R-matrix method for electron energies ranging from 0.01 to 15 eV in close-coupling (CC) approximation. We discuss the multi-channel-coupling effects on the calculated cross sections and resonances, and how the number of excited states included in the target state impacts the convergence of the elastic and the X3B1 → 11A1 and X3B1 → 11B1 excitation cross sections, especially at higher impact energy. Finally, we estimate the accuracy of the 11A1and 11B1 excitation cross sections.
Integral cross sections for elastic electron scattering by methane molecule
Authors: Maljković J B , Vuković J , Tökési K , Predojević B , Marinković B P
Published: June 2020

Synopsis

We have performed a combined experimental and theoretical study of electron elastic differential and integral cross sections from methane molecule (CH4) in the intermediate energy range. Data have been compared with available data sets in the literature as well as with recommended data set [Song et al J. Phys. Chem. Ref.Data
44 023101 (2015)].
Dissociation of furan-2-carboxylic acid by low energy electrons
Authors: Zawadzki M , Kočišek J , Fedor J
Published: June 2020

Synopsis

Electron attachment to molecular target can lead to a variety of negative fragment ions. We experimentally probe the main dissociative electron attachment channels in furan-2-carboxylic acid (C3H3O2 – COOH) - a molecular target composed of two important structural units: a furan ring and a carboxylic group. In our studies we utilise nearly mono-energetic electrons at electron energies from 0 eV up to 15 eV. Our detection setup is based on extraction lens system and quadrupole mass spectrometer, that enables measurement of the energy dependent mass-selected yields of newly formed stable anions.
Investigation of electron scattering asymmetries in halocamphors
Authors: Ruivo J C , Kossoski F , Varella M T do N
Published: June 2020

Synopsis

We present a study on the electron transmission and dissociative electron attachment asymmetries in halocamphor species. Our results consist in their anion state spectra, applied in a model for the spin-polarized electron scattering problem under the influence of a low energy resonance.
Spectroscopic investigations of YAG-laser-driven microdroplet-tin plasma sources of extreme ultraviolet radiation for nanolithography
Authors: Versolato O , Bayerle A , Bayraktar M , Behnke L , Bekker H , Bouza Z , Colgan J , Crespo López-Urrutia J R , Deuzeman M J , Hoekstra R , Kurilovich D , Liu B , Meijer R , Neukirch A , Poirier L , Rai S , Ryabtsev A , Scheers J , Schupp R , Sheil J , Torretti F , Ubachs W , Witte S
Published: June 2020

Synopsis

Highly charged tin ions are the sources of extreme ultraviolet (EUV) light at 13.5-nm wavelength in laser-produced transient plasmas for next-generation nanolithography. Generating this EUV light at the required power, reliability, and stability however presents a formidable task that combines industrial innovations with challenging scientific questions. We will present work on the spectroscopy of tin ions in and out of YAG-laser-driven plasma and present a surprising answer to the key question: what makes that light?
Base damages induced in DNA by 10 eV electrons: contribution to the radiosensitization mechanism of platinum chemotherapeutic drugs
Authors: Liu W , Gao Y , Lemelin V , Zheng Y , Sanche L
Published: June 2020

Synopsis

Binding of Pt-drugs to DNA significantly enhaces base damages, crosslinks, double strand breaks (DSBs) and non-DSB cluster lesions induced by 10 eV electrons. This enhancement of potentially lethal lesions is due to a modification of electron-DNA interactions, which contributes to the synergy between chemo- and radio-therapy, when these modalities are administered in concomitance during cancer treatments.
Solar wind sputtering of lunar analogue material
Authors: Szabo P S , Biber H , Weichselbaum D , Brenner M , Stadlmayr R , Mayer D , Mutzke A , Nenning A , Doppler M , Sauer M , Jäggi N , Galli A , Fleig J , Foelske-Schmitz A , Lammer H , Mezger K , Wurz P , Aumayr F
Published: June 2020

Synopsis

Sputtering by solar wind ions is investigated on thin films of the mineral wollastonite (CaSiO3) as an analogue material for the lunar surface. Sputtering yields are measured with a Quartz Crystal Microbalance (QCM) using H and He ions as well as multiply charged Ar ions at different incidence angles. The results of these irradiations show that kinetic sputtering can be very well reproduced using SDTrimSP, while potential sputtering significantly increases the expected erosion of airless bodies in the solar system.
The role of contaminations on the interaction of highly charged ions with 2D materials
Authors: Niggas A , Schwestka J , Creutzburg S , Aumayr F , Wilhelm R A
Published: June 2020

Synopsis

Contaminations on two dimensional materials can influence electronic, optical or mechanical material properties or even dominate them. We perform ion beam spectroscopy with highly charged ions as projectiles transmitted through freestanding 2D materials to study fundamental charge exchange processes between the ion and the samples under extreme conditions. Various in situ cleaning techniques to remove contaminations such as laser annealing and sample heating are employed. Their influence on our spectroscopy results is discussed here.
Influence of surface plasmon polaritons on heating of gold
Authors: Terekhin P N , Ndione P D , Weber S T , Rethfeld B
Published: June 2020

Synopsis

We present a detailed investigation of periodic heating of gold and periodic structures formation on a surface induced by surface plasmon polaritons (SPP) after irradiation with ultrashort laser pulses. Conditions of the SPP excitation and influence of the angle of incidence and wavelength of the laser field on the resulting structured heating are analysed in detail.