Theoretical studies on the radiative electron capture and subsequent radiative decay in the collision of Xe53+ ions with neutral Xe

Abstract

The radiative electron capture (REC) and subsequent radiative decay of initial hydrogen-like Xe52+ ions are studied in the collision of Xe53+ with Xe atom at a projectile energy of 197 MeV/u within the framework of the multiconfiguration Dirac-Fock method and the density matrix theory. We calculate the differential and total cross sections as well as the REC photon energies for REC to the 1snp1/2, 3/2 Jf=1 (n=2-5) levels of finally helium-like Xe53+ ions. Moreover, the transition energies and rates of the subsequent 1snp3/2 Jf=1 1s2 Jd = 0 decay as well as the angular distribution and linear polarization of the associated characteristic photons are also calculated. It is found that the REC photons are remarkably anisotropic. Through the analysis of the REC angular distribution characteristics, we find that the different configurations of the REC angular distribution are similar in quality, and they all have a peak at the 90. That is to say, the REC process can more easily occur in the direction perpendicular to the incident direction of the projectile ions. In addition, while the characteristic photons from the subsequent 1snp3/2 Jf=11s2 Jd= 0 radiative decay of Xe52+ ions exhibit an anisotropic angular distribution and strong linear polarization, their counterparts from the 1snp1/2 Jf = 1 1s2 Jd = 0 decay are almost isotropic and linearly unpolarized. The angular distribution and linear polarization of the radiation photon decay from the (1s np1/2,3/2 Jf = 0) states to the ground state（1s2 Jd = 0）both reach a maximum value at the 90, their characteristics are similar to those of the REC photons, that is to say, the deexcited process can more easily occur in the direction perpendicular to the incident direction of the projectile ions, and in this direction the decay photons have much larger polarization degree.