Anisotropy of characteristicK-shell x rays from heavy-ion—atom collisions

Inner-shell ionization created by fluorine ions in nearly symmetric collisions

“…The cross sections were obtained from measurements at 135 ~ assuming isotropic X-ray emission. The observed polarization of F K X-rays in F 9 § +Ar collisions at 33MeV [22] would change the given cross section by about 10 %. The measured X-ray cross sections, however, show a variation with the bombarding energy, that is by almost one order of magnitude larger than the corresponding variation of ionization cross sections from statistical model calculations.…”

Magnetic-sublevel population and alignment for the excitation of H- and He-like uranium in relativistic collisions

“…As an example, for radiative electron capture (REC) into high-Z ions, former investigations of angular differential photon emission and alignment of the associated excited states gave access to many subtle details of relativistic atomic collision dynamics as well as of the electronic structure of high-Z ions [21][22][23]. In addition, we like to note that the alignment and polarization phenomena in ion-atom collisions have been studied in several earlier investigations, in particular for low-Z ions (see, for example [24][25][26][27]). The K-shell x-ray radiation produced by electron capture (and in a few cases via excitation) in few-electron ions from target atoms has been found to be anisotropic and the corresponding orientation and alignment parameters have been obtained by measuring the x-ray polarization or angular differential cross sections [24][25][26][27].…”

Oxygen inducedK-shell ionization of selected elements from sulphur to bromine

“…Total cross sections are easily obtained if X-ray emission can be assumed to be isotropic. This has been shown to be correct within a few percent for X-rays induced by proton and e-particle bombardment [22, 231 and recently for bombardment of ar- gon with 33 MeV 19F projectiles [24]. We have assumed isotropic X-ray emission and deduced total X-ray cross sections according to:…”

“…The purpose of this work has been to undertake systematic studies of target K-shell ionization induced by oxygen projectiles (160 and 1sO) on 16S, 19 K, 22Ti, 23 v, 24Cr, 25Mn, 26Fe, 27 CO, 28Ni, 29 Cu, 3oZn, 3zGe and 3sBr. The projectile energy range (7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24) and the range of target elements studied, are in the intermediate region between the strict validity region of Coulomb ionization theories and that of the electron promotion model [2]. Apart from ionization cross sections we report also Ko]K p intensity ratios and K~-and KFline shifts as function of target atomic number and incident projectile energy.…”