| |
 |
UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS Guest
2024-11-22 2:18 |
 |
|
|
|
Conference: Bucharest University Faculty of Physics 2015 Meeting
Section: Theoretical Physics and Applied Mathematics
Title:
R-matrix calculation of singly ionized Carbon structure for x-ray laser modelling
Authors:
Cristian IORGA(1,2), Vasile PAIS(1), Viorica STANCALIE(1)
Affiliation:
1) NATIONAL INSTITUTE OF LASER, PLASMA AND RADIATION PHYSICS
2) BUCHAREST UNIVERSITY, FACULTY OF PHYSICS
E-mail
criiorga@gmail.com
Keywords:
close-coupling calculation, atomic structure, atomic and ionic spectroscopy
Abstract:
This study presents the results of the extensive calculations on electron scattering single ionized carbon ion in laser-plasma environment. An initial calculation has been done to obtain bound-bound and bound-free data for $C^{+}$ states from $(C^{2+} + e^{-})$ scattering problem. The $C^{2+}$ target eigenstates with $2s^{2} (^{1}S^{e}), 2s2p (^{3}P^{o}), (^{1}P^{o})$ and $2p^{2} (^{3}P^{e}), (^{1}D^{e}), (^{1}S^{e})$ plus all terms of the configuration $2s ar{3l}$ and $2par{3l}$, $l=0, 1, 2$ were constructed in terms of seven orthogonal basis orbitals [1], three 'spectroscopic'($1s$, $2s$, $2p$) and four pseudo-orbitals ($ ar{3s}, ar{3p}, ar{3d}, ar{4f}$), the later being included to allow additional correlations. The electron scattering calculations were performed via R-matrix approach while the two electron promotions out of selected
base configurations of C+ were allowed by the codes. The intermediate coupling calculations are carried out on recoupling the LS symmetries in a pair-coupling representation stage of the RMATXI[2]. The (e+core) Hamiltonian matrix is diagonalized for each resulting total angular momentum and parity.
For each autoionizing level we include all possible Auger decay channels and radiative channels leading to stabilized bound states. By using the quantum defect theory it was possible to identify the Rydberg series of resonances. The results of this work initially consist of structure calculations followed by the Rydberg series of resonances, L-shell photo-excitation and photo-ionization processes. Comparisons with available data are provided.
High intensity short pulse laser-produced carbon plasma is simulated to investigate the x-ray emission. Competing processes describing the level population distribution include auto-ionization, Auger decay and collisional ionization of the outer-shell electrons by electrons generated during photo-ionization.
References:
1) K. L. Berrington, P. G. Burke, A. E. Kingston, J. Phys. B At. Mol. Phys. 10, 3117, (1997)
2) K. A. Berrington, W. B. Eissner, P. H. Norrington, Comp. Phys. Com. 92, 290-420, (1995)
Acknowledgement:
This work is partially supported by the Institute of Atomic Physics under project no. F03. Financial support under the Romanian Space Agency coordinated program STAR Project Number 33 is also aknowledged.
|
|
|
|