Electron Correlations in Sequential Two-Photon Double Ionization of an Ar Atom

Dades bibliogràfiques
Parent link:Atoms
Vol. 10, iss. 4.— 2022.— [139, 12 p.]
Autor corporatiu: Национальный исследовательский Томский политехнический университет Школа базовой инженерной подготовки Отделение математики и информатики
Altres autors: Lagutin B. M. Boris Mikhaylovich, Petrov I. D. Ivan Dmitrievich, Sukhorukov V. L. Viktor Lvovich, Kilin V. A. Viktor Andreevich, Novikovsky N. M. Nikolay Mikhaylovich, Demekhin F. V. Filipp Vladimirovich, Ehresmann A. Arno
Sumari:Title screen
Sequential two-photon ionization is a process that is experimentally accessible due to the use of new free-electron laser sources for excitation. For the prototypical rare Ar gas atoms, a photoelectron spectrum (PES) corresponding to the second step of the sequential two-photon double ionization (2PDIII) at a photon excitation energy of 65.3 eV was studied theoretically with a focus on the consequences of electron correlations in the considered process. The calculation predicts many intense lines at low photoelectron energies, which cannot be explained on the basis of a one-electron approximation. The processes that lead to the appearance of these lines include many-electron correlations, either in the first or second step of photoionization. A significant fraction of the intensity of the low-energy part of PES is associated with the Auger decay of the excited states formed at the second step of 2PDI. The shape of the low-energy part of the 2PDIII PES is expected to be dependent on both the energy of photon excitations and the flux of the exciting beam.
Idioma:anglès
Publicat: 2022
Matèries:
Accés en línia:https://doi.org/10.3390/atoms10040139
Format: Electrònic Capítol de llibre
KOHA link:https://koha.lib.tpu.ru/cgi-bin/koha/opac-detail.pl?biblionumber=669369
Descripció
Sumari:Title screen
Sequential two-photon ionization is a process that is experimentally accessible due to the use of new free-electron laser sources for excitation. For the prototypical rare Ar gas atoms, a photoelectron spectrum (PES) corresponding to the second step of the sequential two-photon double ionization (2PDIII) at a photon excitation energy of 65.3 eV was studied theoretically with a focus on the consequences of electron correlations in the considered process. The calculation predicts many intense lines at low photoelectron energies, which cannot be explained on the basis of a one-electron approximation. The processes that lead to the appearance of these lines include many-electron correlations, either in the first or second step of photoionization. A significant fraction of the intensity of the low-energy part of PES is associated with the Auger decay of the excited states formed at the second step of 2PDI. The shape of the low-energy part of the 2PDIII PES is expected to be dependent on both the energy of photon excitations and the flux of the exciting beam.
DOI:10.3390/atoms10040139