English
Related papers

Related papers: Accurate photoionisation cross section for He at n…

200 papers

In a joint experimental and theoretical endeavour, photoionization of metastable C4+(1s 2s 3S1) ions via intermediate levels with hollow, double-K-vacancy configurations 2s2p, 2s3p, 2p3s, 2p3d, 2s4p, 2p4s and 2p4d has been investigated.…

We report the total integrated cross-section (TICS) of two-photon double ionization of helium in the photon energy range from 42 to 50 eV. Our computational procedure relies on a numerical solution of the time-dependent Schr\"odinger…

Atomic and Molecular Clusters · Physics 2026-03-03 I. A. Ivanov , A. S. Kheifets

Accurate photodissociation cross sections have been obtained for the A-X electronic transition of HeH+ using ab initio potential curves and dipole transition moments. Partial cross sections have been evaluated for all rotational transitions…

Astrophysics of Galaxies · Physics 2015-05-28 S. Miyake , C. D. Gay , P. C. Stancil

We present a complete set of analytic fits to the non-relativistic photoionization cross sections for the ground states of atoms and ions of elements from H through Si, and S, Ar, Ca, and Fe. Near the ionization thresholds, the fits are…

Astrophysics · Physics 2008-11-26 D. A. Verner , G. J. Ferland , K. T. Korista , D. G. Yakovlev

Theoretically self-consistent calculations for photoionization and (e + ion) recombination are described. An identical eigenfunction expansion for the ion is employed in coupled channel calculations for both processes, thus ensuring…

Astrophysics · Physics 2007-05-23 Sultana N. Nahar

Absolute cross sections for m-fold photoionization (m=1,...,6) of Fe+ by a single photon were measured employing the photon-ion merged-beams setup PIPE at the PETRA III synchrotron light source, operated by DESY in Hamburg, Germany. Photon…

We present ground state photoionization cross sections of atoms and ions averaged over resonance structures for photoionization modeling of astrophysical sources. The detailed cross sections calculated in the close-coupling approximation…

Astrophysics · Physics 2009-10-30 M. A. Bautista , P. Romano , A. K. Pradhan

We study the ionization process involving antiproton and hydrogen in the energy range between 0.1 keV to 500 keV, using single center close coupling approximation. We construct the scattering wave function using B-spline bases. The results…

Atomic Physics · Physics 2007-05-23 S Sahoo , S C Mukherjee , H R J Walters

We study the total photodetachment cross section of H$^-$ near a repulsive center. An analytical formula for the photodetachment cross section is obtained using the standard closed-orbit theory and extending it to the energy range below the…

Atomic Physics · Physics 2013-08-19 B. C. Yang , J. B. Delos , M. L. Du

Using the photon-ion merged-beams technique at the PETRA\,III synchrotron light source, we have measured cross sections for double and up to tenfold photoionization of La$^{+}$ ions by a single photon in the energy range 820--1400~eV, where…

We present a theoretical method for calculating multiphoton ionization amplitudes and cross sections of few-electron atoms. The present approach is based on an extraction of partial wave amplitudes from a scattering wave function, which is…

Atomic Physics · Physics 2021-04-21 Andrej Mihelic , Martin Horvat

We calculate the distributions in recoil momenta and their energy distributions for the high energy non-relativistic double photoionization of helium caused by the quasifree mechanism of the process. The distributions obtain local maxima at…

Atomic Physics · Physics 2013-03-06 M. Ya. Amusia , E. G. Drukarev , E. Z. Liverts , A. I. Mikhailov

We theoretically investigate the single and double ionization of the He atom by antiproton impact for projectile energies ranging from $3$~keV up to $1000$~keV. We obtain accurate total cross sections by directly solving the fully…

Atomic Physics · Physics 2015-03-06 S. Borbély , J. Feist , S. Nagele , K. Tőkési , L. Nagy , J. Burgdörfer

We have measured the differential cross section for the $\gamma$$^3$He$\rightarrow \pi^+ t$ reaction. This reaction was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Real photons produced with the Hall-B…

Nuclear Experiment · Physics 2011-03-22 Rakhsha Nasseripour , Barry Berman , the CLAS Collaboration

We describe a method for the calculation of photoionization cross-sections using square-integrable amplitudes obtained from the diagonalization of finite-basis set representations of the electronic Hamiltonian. Three examples are…

Atomic Physics · Physics 2017-02-01 Alex Kozlov , Saumitra Saha , Harry Quiney

Total ionization cross sections of H, He, Li, Be, B, C, N, O, F, Ne, P, S and Ar neutral atoms by impact of antiprotons, H^{+}, He^{2+}, Be^{4+}, % C^{6+} and O^{8+}. were calculated using the CDWEIS (continuum distorted wave -Eikonal…

Atomic Physics · Physics 2020-11-13 Jorge E. Miraglia

Experimental and theoretical results are reported for photoionization of Ta-like (W$^{+}$) tungsten ions. Absolute cross sections were measured in the energy range 16 to 245 eV employing the photon-ion merged-beam setup at the Advanced…

The non-relativistic cross section from Rayleigh scattering by hydrogen atoms in the ground state is calculated over a wide range of photon energies ($< 0.8$ keV). Evaluations are performed in terms of the real and imaginary components of…

Atomic Physics · Physics 2022-11-02 René D. Rohrmann , Matías Vera Rueda

A comprehensive study of high-accuracy photoionization cross sections is carried out using the relativistic Breit-Pauli R-matrix (BPRM) method for (hnu + Fe XVII --> Fe XVIII + e). Owing to its importance in high-temperature plasmas the…

Solar and Stellar Astrophysics · Physics 2015-05-27 Sultana N. Nahar , Anil K. Pradhan , Guo-Xin Chen , Werner Eissner

We present calculations of the electron angular distributions in the single ionization of helium by 1-MeV proton impact at momentum transfer of 0.75 a.u. and ejected-electron energy of 6.5 eV. The results using the first and second Born…

Atomic Physics · Physics 2017-11-02 O. Chuluunbaatar , S. A. Zaytsev , K. A. Kouzakov , A. Galstyan , V. L. Shablov , Yu. V. Popov