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Photoionization of aligned excited states in neon by attosecond laser pulses

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 نشر من قبل Juan Jos\\'e Omiste
 تاريخ النشر 2020
  مجال البحث فيزياء
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We describe numerically the ionization process induced by linearly and circularly polarized XUV attosecond laser pulses on an aligned atomic target, specifically, the excited state Ne$^*(1s^22s^22p^5[{}^2text{P}^text{o}_{1/2}]3s[^1text{P}^o])$. We compute the excited atomic state by applying the time-dependent restricted-active-space self-consistent field (TD-RASSCF) method to fully account for the electronic correlation. We find that correlation-assisted ionization channels can dominate over channels accessible without correlation. We also observe that the rotation of the photoelectron momentum distribution by circularly polarized laser pulses compared to the case of linear polarization can be explained in terms of differences in accessible ionization channels. This study shows that it is essential to include electron correlation effects to obtain an accurate description of the photoelectron emission dynamics from aligned excited states.



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