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arXiv · 2110.15690

Twisted electron impact single ionization coincidence cross-sections for noble gas atoms

Abstract

We present the angular profiles of the triple differential cross-section (TDCS) for the (e,2e) process on the noble gas atoms, namely He (1s), Ne (2s and 2p), and Ar (3p) for the plane wave and the twisted electron impact. We develop the theoretical formalism in the first-born approximation. The present study compares the TDCS for different values of orbital angular momentum number $m$ and opening angles $\theta_p$ of the twisted electron beam with that of the plane wave beam. In addition, we also investigate the TDCS for macroscopic atomic targets to explore the influence of opening angle $\theta_p$ of the twisted electron beam on the TDCS. Our results show that the peaks in binary and recoil region shift from the momentum transfer direction. The results also show that for larger opening angles the peaks for $p$-type orbitals split into double-peak structures which are not observed in the plane wave results for the given kinematics. The angular profiles for averaged cross-section show the dependence of TDCS on the opening angles which are significantly different from the plane wave TDCS.

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Nikita Dhankhar, Soham Banerjee, Rakesh Choubisa. 2021-10-29. Twisted electron impact single ionization coincidence cross-sections for noble gas atoms. https://doi.org/10.1088/1361-6455%2Fac7d80

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