bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resonance contribution to electron-impact excitation rate coefficients of helium-like S14+ ions
Authors: Wu Z W , Ren C , Jiang J , Xie L Y , Zhang D H , Dong C Z 
Published: June 2020

Synopsis
Electron-impact excitation rate coefficients of S14+ ions have been studied by using a relativistic flexible atomic code that can account systematically for configuration interactions. Moreover, we also considered the resonance excitation contributions to the rate coefficients. It is found that the contributions of resonance excitation on rate coefficients is very important.
Accurate electron affinity of lanthanum atom
Authors: Lu Y , Tang R , Fu X , Ning C 
Published: June 2020

Synopsis
Atomic lanthanum anion La− is the best candidate for laser cooling of any atomic anions by far. The previous theoretical studies showed that La− has very a complicated electronic structure, which cannot be well resolved by the traditional photoelectron spectroscopy. In the present work, we used the slow-electron velocity-map imaging method in combination with an ion trap to measure the electronic structure of La−. The electron affinity of La is accurately determined to be 4496.97(20) cm−1 or 0.557553(25) eV.
Ab initio investigation of the line-shape parameters for atmosphere-relevant molecular systems
Authors: Jóźwiak H , Thibault F , Cybulski H , Stolarczyk N , Gancewski M , Wcisło P 
Published: June 2020

Synopsis
We demonstrate the results of the first ab initio investigation of the line-shape parameters for two molecular systems important for atmospheric studies: CO-N2 and O2-N2. We provide the pressure broadening and shift coefficients with their speed dependencies for purely rotational lines, calculated from highly accurate potential energy surfaces with the close-coupling scheme. This is the first, fully quantum approach to the problem of determination of the spectral line shapes for the systems important for terrestrial atmospheric measurements.
Pressure manipulation of exciton dynamics in few-layered MoS2
Authors: Li Q , Sui L , Jiang Y , Chen A , Jin W , Liu H , Yuan K , Jin M 
Published: June 2020

Synopsis
Transition metal dichalcogenides have recently attracted great interest as an important class of two-dimensional semiconductors because of their distinctive electronic, optical and catalytic properties. Here we demonstrate the first experimental study on ultrafast excited state dynamics of few-layered molybdenum disulfide under high pressure by means of broadband transient absorption spectroscopy combined with diamond anvil cell devices.
Probing functional group dependence in dissociative electron attachment using negative ion momentum imaging
Authors: Gokhale S , Gope K , Tadsare V , Bain M , Raghav A , Ashfold M N R , Krishnakumar E , Prabhudesai V S 
Published: June 2020

Synopsis
Dissociative electron attachment (DEA) is the most efficient way to explore the structure and dynam-ics of excited states of molecular negative ions. More importantly, DEA has been shown to be a tool for chemical control. One crucial aspect of the chemical control using DEA is the functional group dependence present in this process. Here we present cases on the effect of delocalized electrons on DEA patterns observed in simple aromatic compounds.
Uncertainty assessment of Rydberg and doubly-excited molecular states ab initio calculations using Quantum Defect Theory scaling laws
Authors: Telmini M , Jungen Ch 
Published: June 2020

Synopsis
We discuss the accuracy of various published ab initio calculations of highly excited Born-Oppenheimer bound and doubly excited states in diatomic molecules. We show that some of these results appear questionable and in a few cases even clearly unreliable, a fact which may also affect the prediction of collision cross sections based on such data. Our analysis uses Quantum Defect Theory scaling laws and is supported by variational R-matrix calculations. Some simple recipes are discussed, which may help users of ab initio quantum chemistry packages to assess the quality of their results.
Electron emission from CH4 molecule induced by 5.5 MeV/u bare C ions
Authors: Mandal A , Bagdia C , Roychowdhury M , Monti J M , Rivarola R D , Tribedi L C 
Published: June 2020

Synopsis
We present the experimental and theoretical study of electron emission from methane (CH4) in collisions with 5.5 MeV/u bare carbon projectiles. We have measured double differential cross section of electron emission and compared the data with the prior form of the continuum distorted wave – eikonal initial state (CDW-EIS) model calculation. The CDW-EIS calculations are in very good agreement with the data.
Impact parameter sensitive study of inner-shell atomic processes in Xe54+, Xe52+ → Xe collisions
Authors: Gumberidze A , Kozhuharov C , Zhang R T , Trotsenko S , Kozhedub Y S , Du R D , Bois H , Beyer F. , Blumenhagen K-H , Brandau C , Bräuning-Demian A , Chen W , Forstner O , Gao B , Gassner T , Grisenti R E , Hagmann S , Hillenbrand P-M , Indelicato P , Kumar A , Lestinsky M , Litvinov Yu A , Petridis N , Schury D , Spillmann U , Trageser C , Trassinelli M , Tu X , Stöhlker Th 
Published: June 2020

Synopsis
In this work, we present a pilot experiment in the experimental storage ring (ESR) at GSI devoted to impact parameter sensitive studies of inner shell atomic processes for bare and He-like xenon ions (Xe54+, Xe52+) colliding with neutral xenon gas atoms. The projectile and target x-rays have been measured at different observation angles for all impact parameters as well as for the impact parameter range of ∼35 - 70 fm.
Energetic processing of hydrocarbons molecular species by ionizing radiation towards the formation of cyclic species
Authors: Indrajith S , Kočišekt J , Domaracka A , Rousseau P , Huber B A 
Published: June 2020

Synopsis
Here we report on experimental studies of the collisions between butadiene clusters and three different ionizing radiation sources: 70 eV electrons, 270 nm photons and 3 keV Ar+ ions. New molecular species are produced by growth mechanism inside of clusters.
Energy deposit by electron excitation in CnN+ projectiles (n=1-3) colliding at in termediate velocity with He atoms : semi-empirical estimates and calculations
Authors: Mahajan T , Béroff K , Pons B , Illescas C , Chabot M , Idbarkach T , Jorge A , Aguirre N F , Diaz-Tendero S 
Published: June 2020

Synopsis
Using measured dissociation branching ratios and theoretical dissociation energies, we extracted semi-empirical estimates of the energy deposit due to electron excitation in CnN+-He collisions at v=2.2 a.u. We compared these estimates to calculations based on the IAE (Independent Atom and Electron) model where the atom(ion)-atom excitation is treated within the Classical Trajectory Monte Carlo (CTMC) approach. A good agreement has been found. This atomic approach is also able to reproduce the experimental Kinetic Energy Release (KER) in CN+ dissociation measured in 3.5 a.u CN+-He collision.
Femtosecond nonadiabatic cascade and subsequent photofragmentation of XUV excited caffeine molecule
Authors: Yamazaki K , Marciniak A , Maeda S , Reduzzi M , Despré V , Hervé M , Meziane M , Niehaus T , Loriot V , Kuleff A , Schindler B , Compagnon I , Sansone G , Lépine F 
Published: June 2020

Synopsis
We found that the XUV excited caffeine undergoes nondadabatic cascade via more than 100 shake-up states within the time constant of 40 fs by using femtosecond XUV-NIR pump-probe photo-ion spectroscopy and the SAC-CI level of ab-initio many-body theory. This nonadiabatic cascade results in the photofragmentation to specific large fragments. Furether ionization by NIR probe during the cascade increases the small fragments CH3
+, CO+
etc. This results show that both vibronic coupling and electron correlation are the keys for the femtochemistry in the highly-correlated electronic excited states.
L-changing through very-long-range interactions in high-n, n∼300, Rydberg-Rydberg collisions
Authors: Yoshida S , Burgdörfer J , Fields G , Brienza R , Dunning F B 
Published: June 2020

Synopsis
State-changing in thermal-energy collisions between strontium atoms in high-n, n∼300, n1F3 Rydberg states is studied in an atomic beam and analyzed using classical trajectory Monte Carlo simulations. The L-changing cross section is large, ∼10-4 cm2, much greater than the corresponding “hard-sphere” cross section.
Model for vibronic excitation of CH+ by resonant scattering of electron
Authors: Jiang X , Yuen C , Cortona P , Kokoouline V , Ayouz M 
Published: June 2020

Synopsis
A new model for theoretical study of vibronic (de-)excitation (including vibrational (de-)excitation) cross sections of CH+ by electron impact was developed based on the multichannel quantum defect theory (MQDT) close-channel-elimination procedure and vibrational-frame-transformation theory of Chang and Fano. The successful application of this model suggested a promising calculation method for vibronic (de-)excitation of diatomic ion core by resonant scattering of electron.
Ionization cross-sections of L-shell and L-subshells by electron impact
Authors: Patoary M A R , Shorifuddoza M , Haque A K F , Uddin M A 
Published: June 2020

Synopsis
Vaisburd and Evdokimov proposed an empirical VE model to calculate the electron impact single ionization cross-sections of atoms and molecules. The extension of the modified VE model (MVE) has been proposed incorporating the relativistic effects. This model is applied to investigate the total L-shell as well as L1-, L2- and L3-subshells ionization cross-sections of various atomic targets with atomic numbers Z =1892 for incident energies up to 1 GeV. The results from the MVE model are compared with the available experimental data and theoretical findings.
Quantum vortex surfaces: a dizzying new effect in single ionization collisions
Authors: Navarrete F , Barrachina R O 
Published: June 2020

Synopsis
We study the appearance of quantum vortices in the transition matrix element of single ionization collisions. We relax all the usual geometrical restrictions on the momenta of the final-state, and demonstrate that previously observed vortex points and lines correspond to 2D and 3D intersections of a much more complex structure: a quantum vortex surface. Finally, we theoretically evaluate this complex structure for the single ionization of hydrogen by positron impact.
Improvement of the target continuum state in distorted wave theories: a dynamic-depending charge
Authors: Rojas M F , Monti J M , Quinto M A , Rivarola R D 
Published: June 2020

Synopsis
In order to improve the representation of the residual-target final state whilst maintaining low computational times, a dynamic-depending charge defined by the emission energy and angle of the ionized electron is considered in the residual-target continuum state.
Photoionization of low-charged silicon ions
Authors: Buhr T , Stock S O , Perry-Sassmannshausen A , Reinwardt S , Martins M , Ricz S , Müller A , Fritzsche S , Schippers S 
Published: June 2020

Synopsis
Single and multiple photoionization of Si1+, Si2+, and Si3+ ions have been investigated near the silicon K-edge using the PIPE setup at beamline P04 of the synchrotron light source PETRA III operated by DESY in Hamburg, Germany. Pronounced resonance structures are observed for all ions which are associated with excitation or ionization of a K-shell electron. The experimental cross sections are compared with results from theoretical calculations.
Coulomb explosion of polycyclic aromatic hydrocarbons induced by heavy cosmic rays: carbon chains production rates
Authors: Chabot M , Béroff K , Dartois E , Pino T 
Published: June 2020

Synopsis
The interstellar medium contains both polycyclic aromatic hydrocarbons and cosmic rays. The frontal impact of a single heavy cosmic ray strips out many electrons. The highly charged species then relax by multi-fragmentation, potentially feeding the interstellar medium with hydrocarbon chains. We model both ionization(s) and fragmentation processes and compute the fragments production rates of particular interest for astrophysical models.
Experimental alternative to investigate the radiation-induced radical chemistry at the molecular level
Authors: Beydoun A , Lecomte F , Nieuwjaer N , Desfrançois C , Manil B 
Published: June 2020

Synopsis
This project aims to develop an original approach to investigate the damage at the molecular level on biomolecules from the indirect irradiation effects. We will construct a new device to put biomolecules in the gas phase, based on the soft laser desorption from microdroplets directly into vacuum, and this source will be coupled with an irradiation platform.
Nitrogen K-shell photoionization of NO+
Authors: Gharaibeh M F , Bizau J M , Cubaynes D , Guilbaud S , El Ghazaly M O A , Al Hagan O A 
Published: June 2020

Synopsis
Photoionization measurements of NO+ at Nitrogen K-shell, performed at the SOLEIL Light Source will be presented. The main observed structure corresponds to the 1s to π* resonant transition.
Radiative and Auger cascades in Fe3+
Authors: Jonauskas V , Drabužinskis P , Kučas S , Koncevičiūtė J 
Published: June 2020

Synopsis
Radiative and Auger cascades following creation of the 2s or 2p shell vacancy in the Fe2+ ion are studied by performing calculations for energy levels and subconfigurations. Radiative and Auger spectra and charge state distribution determined by cascade are investigated. Branching ratios of the cascade are analyzed and main decay mechanisms are identified for all levels of the studied configurations.
Cascade of elementary processes in Se1+
Authors: Jonauskas V , Kučas S , Masys Š , Koncevičiūtė J 
Published: June 2020

Synopsis
Analysis of radiative and Auger cascade following creation of the K shell vacancy in the Se atom is presented. Calculations of radiative and Auger transition probabilities are performed by using Dirac-Fock-Slater approximation. Radiative and Auger spectra as well as ion yield produced by cascade are studied.
Absolute cross sections for electron capture and loss of O+ in water molecule
Authors: Oliveira V , Gomes A H A , Santos A C F , Tőkési K 
Published: June 2020

Synopsis
Absolute cross sections for single and double electron loss and single and double electron capture for O+ projectiles colliding with water vapor have been measured. In addition, we have performed many-body clas-sical trajectory Monte Carlo calculations, where the O+ projectile was either one or more particle, depending on the model used. The water target is modeled as two virtual particles. The calculated cross sections are in agree-ment with the experimental data.
Photoemission delays in 2D model molecules
Authors: Wurmser B , Labeye M , Taïeb R , Caillat J 
Published: June 2020

Synopsis
Photoelectron spectroscopy is one of the main techniques used to probe matter since the understand-ing of the photoelectric effect. Within the last decade, a new aspect has been given to spectroscopy, revisiting it in the time domain. It allows one to resolve the electron dynamics at the attosecond (10−18 s) time scale. Achieving such resolution experimentally brought one to establish innovative set up, and theoretical background is needed to validate, predict and interpret measurements. Much progress has been made in the attoscience field, this work is a step forward in understanding the electron dynamics for molecular continuum states at the attosecond timescale.
Single electron capture cross sections for collisions of multi-charged ions with helium-like atomic system
Authors: Samaddar S , Purkait K , Purkait M 
Published: June 2020

Synopsis
A four-body distorted wave method (DW-4B) is applied to calculate the total cross section for single electron capture in the collisions of multi-charged ions with helium-like atomic system. The proper long range behavior of the Coulomb potential is introduced. The present theoretical method is satisfactory in the intermediate and high-energy regime and is quite reliable compared to other theoretical methods.
Ionization and electron capture in Li3+ + H2O collisions
Authors: Illescas C , Lombana M A , Méndez L , Rabadán I , Suárez J 
Published: June 2020

Synopsis
Total cross sections for ionization and electron capture in Li3+ + H2O collisions are calculated at energies 20 ⩽ E ⩽ 750 keV/u. Three different models are applied: the classical trajectory Monte Carlo method, an expansion in terms of asymptotic-frozen-molecular-orbitals and the numerical solution of the time dependent Schrödinger equation. One-electron transition probabilities from the three methods show general good agreement and with those from the calculation of Luna et al Phys Rev. A
93, 052705.
Cross sections for electron capture process of biological molecules by proton and α-particle impact
Authors: Purkait K , Purkait M 
Published: June 2020

Synopsis
Distorted wave model has been used to predict total cross sections (TCSs) of single electron capture process for several ion-biological molecule collisional systems in the intermediate and high energy regime. TCSs are calculated in the Independent Electron Model (IEM) In this work, we studied with water, nitrogen, oxygen, methane, adenine or cytosine targets impacted by protons and α-particles with kinetic energy ranging from 25 keV/amu to 10,000 keV/amu. It is observed that the present investigation produces results which are in good agreement with experimental observations for all cases.
Quasi-equilibrium in charge-state evolution for 1.0 and 2.0 MeV/u carbon ions after carbon foil penetration
Authors: Imai A M , Sataka M , Matsuda M , Okayasu S , Kawatsura K , Takahiro K , Komaki K , Shibata H , Nishio K 
Published: June 2020

Synopsis
After our observation of “quasi-equilibrium” in charge-state evolution for 2.0 MeV/u sulfur ions after carbon foil penetration, we have extended the initial ions to 1.0 and 2.0 MeV/u carbon ions. A significant quasi-equilibrium was observed for 1.0 MeV/u C+C collisions, where the equilibrium mean charge-state was 4.9, while for 2.0 MeV/u C+C collisions, where the equilibrium mean charge-states was 5.6, was a weak quasi-equilibrium.
Single and double electron capture associated with characteristic K-shell X-ray emission for F9+,8+,7++Ar
Authors: La Mantia D S , Kumar P N S , Tanis J A 
Published: June 2020

Synopsis
Cross sections for target Ar K-shell ionization associated with single and double electron capture, as well as the corresponding cross sections for total electron capture and the projectile F K x rays, were determined for 1.8-2.2 MeV/u F9+,8+,7+ projectiles. The Ar K x-ray coincidence cross section ratios for double to single capture are found to vary strongly with the incident charge state, with the ratios for F9+ well exceeding unity.
Production of molecular dications by electron impact investigated by (e, e+ion) measurement
Authors: Xu S , Wang Y , Ma C , Li Y , Zhou J , Ding L , Xu Z F , Dorn A , Ren X 
Published: June 2020

Synopsis
We present (e, e+ion) measurements for double ionization of nitrogen and oxygen molecules employing the reaction microscope in which the momentum vectors for final-state charged reaction products are determined experimentally. By measuring the final state electrons in coincidence with the molecular dication, the related electronic states and, thus, the production mechanisms of these dications could be identified and studied in detail.
Non-local complex potential theory of dissociative electron attachment: inclusion of two vibrational modes
Authors: Ambalampitiya H B , Fabrikant I I 
Published: June 2020

Synopsis
The nonlocal complex potential theory is developed to treat the dissociative electron attachment to molecules when more than one vibrational mode is allowed in the neutral molecule. Temperature-averaged cross sections for electron attachment to CF3Cl are obtained assuming two vibrational degrees of freedom.
Theoretical study of vibrational excitation and dissociative electron attachment of NO2 by an electron impact
Authors: Liu H , Santos S F , Yuen C , Cortona P , Kokoouline V , Ayouz M 
Published: June 2020

Synopsis
Cross sections for vibrational excitation and dissociative electron attachment (DEA) of the nitrogen dioxide (NO2) molecule in collisions with low-energy electrons are determined theoretically. The thermally-averaged rate coefficients of vibrational excitation are presented for the temperatures from 10 K to 10000 K. The obtained DEA cross section for NO2 agrees well with experimental data.
Electron elastic collisions with Pu, Am and Lr actinide atoms
Authors: Msezane A Z , Felfli Z 
Published: June 2020

Synopsis
The robust Regge-pole methodology which embeds the crucial electron correlations and the vital core-polarization interaction is used to explore negative-ion formation in the actinide atoms Pu, Am and Lr through the electron elastic total cross sections (TCSs) calculation. The TCSs are found to be characterized by ground, metastable and excited anionic formation, whence we extract the anionic binding energies and compare them with existing electron affinities. The TCSs exhibit both atomic and molecular behavior in addition to polarization-induced metastable TCSs.
Scattering of e∓ from H2O
Authors: Haque A K F , Shorifuddoza M , Patoary M A R , Uddin M A 
Published: June 2020

Synopsis
Theoretical differential, elastic, total, momentum transfer, viscosity cross sections and spin-polarization for the elastic scattering of e∓ by H2 O molecule in the energy range 10 eV-10 keV have been calculated. These calculations have been carried out within the framework the Dirac partial wave analysis. We have employed a complex optical potential and additivity rule (AR) to compute the cross sections. Present results reasonably agree with available experimental data and other theoretical findings.
Separation of electronic states for small molecular ions by the mobility measurements in cooled He gas
Authors: Yamazaki T , Mori K , Tanuma H 
Published: June 2020

Synopsis
In some cases of the ion mobility measurements in cooled He gas, we have observed the separation of electronic states for small molecular ions. Both NH+ and ND+ show the separation of X2Π and a4Σ states. The meta-stable

ND

2
+

and

NH

3
+

were observed, but these of

NH

2
+

and

ND

3
+

do not appear in the measurements. The reason of the isotope dependence in mobility measurement is discussed using the calculated potential energy curves for

NH

2
+

and

ND

2
+

.
New magnetized electron beam apparatus and measurement of total electron scattering cross section of N2O at intermediate energy region
Authors: Pyun H , Kim D C , Kim Y , Choi Y R , Park Y , Song M-Y , Kim Y-W , Yoon J-S , Cho H , Sullivan J P , Buckman S J 
Published: June 2020

Synopsis
A new electron scattering apparatus is developed based on concepts from the positron system built by Surko et al. In an electron-version of the system, the electron beam is provided by a cathode and the rest of the system is correspondingly modified to a simpler system. The system was tested with argon to verify its operation. N2O is important in atmosphere and plasma, and in the intermediate energy region, there are two previous results which are in disagreement. We present here a result for the total electron cross section of N2O.
Energy loss of laser-accelerated ions in dense ionized matter
Authors: Zhao Y , Ren J , Deng Z , Qi W , Cheng R , Wang X , Liu W , Ma B , Yin S , Chen B , Feng J , Wang S , Fan Q , Cui B , Zhou X , Zhou W , Cao L 
Published: June 2020

Synopsis
Knowledge about the energy loss of heavy ion in dense ionized matter is of great importance in fields such as inertial confinement fusion, fast ignition as well as intense heavy ion beam driven high energy density physics. The energy loss of 3.4 MeV proton in TAC foam plasma was measured on the XGIII laser facility. It was found that the measured energy loss is far above the Beth prediction.