Study On The Single And Double K-shell Vacancies Production In Atom In The Collision Between Hydrogenlike Cesium Ion And Gas Target

The research on the production of vacancies in the inner shell of atoms caused by ion beam collisions is an important direction in the field of atomic physics,and it also has important scientific significance in the fields of astrophysics and plasma physics.The measurement of the cross-section of the inner-shell vacancies production is very important to test the existing collision theory and establish a new theoretical system.The phenomenon of atomic inner shell ionization caused by low-energy and low-charge state ions has been widely studied,but limited by the popularity of large-scale heavy ion accelerators,the research on atomic inner-shell ionization caused by high-energy and high-charge state ions is still seldom touched.This work is based on the heavy ion accelerator cooling storage ring and its gas inner target device.By measuring the X-rays emitted during the collision of 66.3 Me V/u Cs⁵⁴⁺ions with gas Kr targets and Ar targets,the production cross-sections of the K-shell single and double holes of the Kr target are 3.163×10⁵ barn and 7.630×10⁴ barn respectively,and the Ar target K-shell single,The production cross sections of double holes are 1.134×10⁶ barn and 3.521×10⁵ barn,respectively.Theoretically,the ionization cross-sections and electron capture cross-sections K-shell of target K-shell calculated by the continuum distorted-wave-eikonal initial state approximation method（CDW-EIS）and relativistic eikonal approximation method（CEIK）,respectively.Furthermore,the cross section of target atom K-shell hole production is obtained.The research results show that the Kαsatellites and hypersatellites emitted by Kr and Ar atoms are all isotropic,and the resulting K-shell hole production cross-sections are consistent with the theoretical values.This result shows that CDW-EIS and CEIK theory can describe the production of K-shell holes of target atoms under the current collision system.The electron transfer process is dominant in the K-shell hole production mechanism of the Kr target,while the direct ionization process is dominant in the Ar target.In order to study the characteristics of L-shell bystander holes producted by K-shell holes,we obtained the average number of L-shell bystander holes,n _L.The results show that n _L is basically consistent with the scale relationship given by Horvat et al.,and both are smaller than the prediction results of the geometric model.The absolute cross-section measurement experiment of atomic inner shell holes producted by heavy ion collisions on the inner target terminal of the cooling storage ring of HIRFL has laid a foundation for the future research on hollow atoms on the new production of high-current heavy ion accelerator HIAF.