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arXiv · 2603.03905

Angular distribution of K{\alpha} x rays following nonradiative double electron capture in relativistic collisions of Xe54+ ions with Kr and Xe atoms

Abstract

We present experimental study of nonradiative double electron capture processes in collisions of 95 and 146 MeV/u bare xenon ions with krypton and xenon gaseous atoms at the HIRFL-CSR storage ring. Angular distributions of the characteristic K{\alpha} radiation of the down-charged projectile ions Xe52+* are measured, which are closely related to the magnetic sublevel population of the excited 1s2l_j states of Xe52+*. It was found that the K{\alpha}1 radiation shows pronounced anisotropic and is sensitive to the collision energies and the target atoms, whereas the K{\alpha}2 radiation gives rise to isotropic. Moreover, obviously difference in the anisotropy parameters of Lyman-{\alpha}1 of Xe53+* ions and K{\alpha} transitions of Xe52+* ions separately following nonradiative single and double electron capture into the L-shell levels of projectiles is obtained and discussed.

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Bian Yang, Deyang Yu, Konstantin N. Lyashchenko, Caojie Shao, Zhongwen Wu, Mingwu Zhang, Oleg Yu. Andreev, Junliang Liu, Zhangyong Song, Yingli Xue, Wei Wang, Fangfang Ruan, Yehong Wu, Rongchun Lu, Chenzhong Dong, Xiaohong Cai. 2026-03-04. Angular distribution of K{\alpha} x rays following nonradiative double electron capture in relativistic collisions of Xe54+ ions with Kr and Xe atoms. https://arxiv.org/abs/2603.03905

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