K-shell photoionization of Be-like nitrogen from the ground state: energies and Auger widths of the high-lying double-excited states for N IV

2018 ◽  
Vol 96 (11) ◽  
pp. 1183-1191
Author(s):  
Liang Liang ◽  
Chao Zhou
Keyword(s):  
Cross Sections ◽  
Ground State ◽  
Photoionization Cross Section ◽  
Coupling Scheme ◽  
Close Coupling ◽  
Resonance Energies ◽  
Auger Spectra ◽  
Distorted Wave Method ◽  
Theoretical Results ◽  
Good Agreement

The K-shell photoionization cross section of Be-like nitrogen (N IV) from the ground state is studied with the R-matrix and distorted-wave method for photon energies from 5.7 to 41.2 Ry. The close-coupling expansion includes 34 target states of N V with the 13 configurations in the LS-coupling scheme. The resonance energies, quantum defect and widths of 18 series of autoionization are determined from QB method and agree with these by cross sections. Our theoretical resonance energies and widths are compared with the existing experiments on the Auger spectra and other theoretical results. The results show that the calculated resonance energies are in rather good agreement with the experiment on the Auger spectra. For the autoionization width of some resonance states, good agreement is also found with recent theoretical results wherever available obtained using a saddle-point complex-rotation method.

Photoionization of Al X from ground state using the relativistic R-matrix close-coupling method

2014 ◽  
Vol 92 (3) ◽  
pp. 241-245 ◽  
Author(s):  
Liang Liang ◽  
Xu-yang Liu ◽  
Chao Zhou
Keyword(s):  
Cross Sections ◽  
Ground State ◽  
Energy Levels ◽  
Resonance Energy ◽  
Photoionization Cross Section ◽  
Rydberg Series ◽  
Close Coupling ◽  
R Matrix ◽  
Target States ◽  
Distorted Wave Method

The relativistic R-matrix method is used to calculate the total photoionization cross sections from the ground state 1s22s2 1S0 of Al X for photon energies ranges from the first ionization threshold to just above the eighth threshold of the residual ion Al XI. In this work, the relativistic distorted-wave method is employed to calculate the fine-structure energy levels and radial functions. The lowest eight level target states of Al XI are used in the photoionization calculations of Al X and should provide a reasonably complete database for practical application for photoionization cross section for Al X. The resonance energy levels and widths of 18 Rydberg series have been investigated.

scholarly journals Electron Scattering from the Ground and Excited States of Barium

1999 ◽  
Vol 52 (3) ◽  
pp. 603
Author(s):  
Dmitry V. Fursa
Keyword(s):  
Excited States ◽  
Electron Scattering ◽  
Cross Sections ◽  
Differential Cross ◽  
Ground State ◽  
Differential Cross Sections ◽  
Close Coupling ◽  
Angular Correlations ◽  
Electron Photon ◽  
Good Agreement

We have used the nonrelativistic convergent close-coupling (CCC) method to investigate electron scattering from the ground (6s2)1S state and excited (6s6p)1 Po1 and (6s5d)1,3De2 states of barium. For the scattering from the barium ground state, we have found very good agreement with measurements of (6s6p)1 Po1 apparent cross sections at all energies. Similarly, good agreement is found for differential cross sections for elastic scattering and (6s6p)1 Po and (6s5d)1 De2 excitations and with the (6s6p)1 Po1 state electron{photon angular correlations. For the scattering from excited states of barium we have found good agreement with elastic (6s6p)1 Po1 scattering and the (6s5d)1De2 → (6s6p)1 Po1 transition for both differential cross sections and electron–photon angular correlations.

Electron excitation of the Group IV elements

2002 ◽  
Vol 80 (6) ◽  
pp. 687-696 ◽  
Author(s):  
R Srivastava ◽  
R P McEachran ◽  
A D Stauffer
Keyword(s):  
Cross Sections ◽  
Ground State ◽  
Silicon Germanium ◽  
Electron Excitation ◽  
Group Iv ◽  
Coupling Scheme ◽  
Distorted Wave ◽  
J Coupling ◽  
Group Iv Elements ◽  
Distorted Wave Method

We investigated the electron excitation of the fine-structure levels of the 3P ground state and the first excited 1D state of the first four elements of Group IV: carbon, silicon, germanium, and tin. These calculations were carried out in the j–j coupling scheme using the relativistic distorted-wave method. Results are presented for the differential cross sections and spin-polarization parameters for incident electron energies of 25 and 40 eV. PACS Nos.: 34.80Dp, 34.80Nz

scholarly journals Study of sub-barrier fusion of 36S+50Ti,51V systems

2019 ◽  
Vol 223 ◽  
pp. 01013
Author(s):  
Giulia Colucci ◽  
Giovanna Montagnoli ◽  
Alberto M. Stefanini ◽  
Kouichi Hagino ◽  
Antonio Caciolli ◽  
...  
Keyword(s):  
Experimental Data ◽  
Comparative Study ◽  
Excitation Function ◽  
Ground State ◽  
Weak Coupling ◽  
Coupling Scheme ◽  
Excitation Functions ◽  
Coupled Channels ◽  
Barrier Distribution ◽  
Good Agreement

A detailed comparative study of the sub-barrier fusion of the two near-by systems 36S+50Ti,51V was performed at the National Laboratories of Legnaro (INFN). Aim of the experiment was the investigation of possible effects of the non-zero spin of the ground state of the 51V nucleus on the sub-barrier excitation function, and in particular on the shape of the barrier distribution. The results sh w that the two measured excitation functions are very similar down to the level of 20 - 30 μb. The same is observed for the two barrier distributions. Coupled-channels calculations have been performed and are in good agreement with the experimental data. This result indicates that the low-lying levels in 51V can be interpreted in the weak-coupling scheme, that is, 51V(I) = 50Ti(2+)⊗ p(1 f7/2).

1s hole excited states of Be: partial autoionization rates compared with recent experimental data

1991 ◽  
Vol 69 (5) ◽  
pp. 603-605
Author(s):  
D. Petrini ◽  
J. A. Tully
Keyword(s):  
Experimental Data ◽  
Excited States ◽  
Cross Section ◽  
Ground State ◽  
Photoionization Cross Section ◽  
Recent Experimental Data ◽  
Auger Decay ◽  
Close Coupling ◽  
University College London ◽  
The University

Auger decay following inner-shell photoexcitation of atomic beryllium is studied using the University College London close-coupling codes. We reproduce some of the features observed experimentally by Krause and co-workers. The vastly predominant decay mode of Be 1s2s2np1P° is to Be+ 1s2np rather than the ground state of Be+ and the theoretical np/2s ratio agrees with the experimental value. The peak observed in the partial photoionization cross section for formation of 1s(2s2p3P) 2P° is due to photoexcitation of 1s2s(3s3p3P) 1P° followed by autoionization. Our theoretical result reproduces this feature. Strong configuration interaction effects limit the accuracy we can achieve for the radiationless decay width.

In-Plane Vibrations of Thick Circular Rings With T or I Cross Sections

1979 ◽  
Vol 46 (2) ◽  
pp. 470-472
Author(s):  
H. Lecoanet ◽  
J. Piranda
Keyword(s):  
Experimental Data ◽  
Eigenvalue Problem ◽  
Cross Section ◽  
Cross Sections ◽  
Rectangular Cross Section ◽  
Circular Rings ◽  
Theoretical Results ◽  
Good Agreement

This paper deals with the problem of eigenfrequencies and eigenvectors for rings whose cross section may be decomposed in basic rectangular cross sections. The solution is derived from a solution of the in-plane eigenvalue problem for rectangular cross-section thick rings. A good agreement between theoretical results and experimental data is obtained.

scholarly journals Cross Section Ionization By Electron Impact Of Helium Like Ions

2021 ◽  
Author(s):  
Manel Hariz Belgacem ◽  
Elhabib Guedda ◽  
Haikel Jelassi
Keyword(s):  
Electron Impact ◽  
Cross Section ◽  
Cross Sections ◽  
Ground State ◽  
The Cross ◽  
State 1 ◽  
Unstable States ◽  
Good Agreement

<sub></sub> In this paper we present our calculation of the cross section ionization by electron impact of C V, N VI and O VII. Using the Flexible Atomic Code (FAC), we obtain the cross sections for the ionization of these ions from the ground state 1<sup>1</sup>S, and from the unstable states 2<sup>1</sup>S and 2<sup>3</sup>S. Our results are in good agreement with those based on the Coulomb Born (CB) approximation and the available measurements.

scholarly journals The Dynamics of the S(1D)+H2/D2 Reactions at Low Temperature via Statistical Simulations

2020 ◽  
Vol 3 (1) ◽  
pp. 9-16
Author(s):  
Tomas Gonzalez-Lezana ◽  
Pascal Larrégaray ◽  
Laurent Bonnet
Keyword(s):  
Cross Sections ◽  
Quantum Model ◽  
Space Theory ◽  
Collisional Energy ◽  
Energy Regime ◽  
Phase Space Theory ◽  
The Mean ◽  
Statistical Approaches ◽  
Theoretical Results ◽  
Good Agreement

Two different statistical approaches, the statistical quantum model (SQM) and the mean potential phase space theory (MPPST), have been employed to calculate the integral cross sections for the reactive collisions between S(1D) and H2/ D2  in the low energy regime (below 0.3 eV collisional energy). The rate constant for the S(1D) + H2 → SH + H reaction has been also obtained and compared with previously reported experimental and theoretical results. The good agreement shows the capability of these two methods to study the dynamics of these complex-forming atom-diatom processes in the present energy regime.

scholarly journals Rotational quenching of HD induced by collisions with H2 molecules

2019 ◽  
Vol 488 (1) ◽  
pp. 381-386
Author(s):  
Yier Wan ◽  
N Balakrishnan ◽  
B H Yang ◽  
R C Forrey ◽  
P C Stancil
Keyword(s):  
Potential Energy ◽  
Potential Energy Surface ◽  
Cross Sections ◽  
Energy Surface ◽  
Rate Coefficients ◽  
Quantum Mechanical ◽  
Cooling Efficiency ◽  
Close Coupling ◽  
Rotational Transitions ◽  
Good Agreement

ABSTRACT Rate coefficients for rotational transitions in HD induced by H2 impact for rotational levels of HD j ≤ 8 and temperatures 10 K ≤ T ≤ 5000 K are reported. The quantum mechanical close-coupling (CC) method and the coupled-states (CS) decoupling approximation are used to obtain the cross-sections employing the most recent highly accurate H2–H2 potential energy surface (PES). Our results are in good agreement with previous calculations for low-lying rotational transitions The cooling efficiency of HD compared with H2 and astrophysical applications are briefly discussed.

On the computation of dipole transitions in the HD molecule. Part II

1976 ◽  
Vol 54 (6) ◽  
pp. 672-679 ◽  
Author(s):  
L. Wolniewicz
Keyword(s):  
Ground State ◽  
Wave Functions ◽  
Nonadiabatic Coupling ◽  
Transition Moments ◽  
The Mean ◽  
Variational Wave Functions ◽  
Theoretical Results ◽  
Variational Wave ◽  
Electronic Ground ◽  
Good Agreement

The nonadiabatic coupling with Πu states in the electronic ground state of the HD molecule is discussed. Formulas are given that facilitate the evaluation of Πu contributions to the energies and transition moments. Numerical computations are performed for all ν ≤ 4 vibrational and J ≤ 4 rotational levels yielding the Πu and Σu nonadiabatic corrections. The variational wave functions are employed to compute the transition moments for the 0–ν bands with ν ≤ 4. The results are in good agreement with experimental data except in the case of the 0–ν band where the theoretical results are larger than the mean experimental moment by a factor of about 1.4.

Sign in / Sign up

Export Citation Format

Share Document