Measurement of High-Energy Charge-Transfer Cross Sections for Incident Protons and Atomic Hydrogen in Various Gases

Charge States and Charge-Changing Cross Sections of Fast Heavy Ions Penetrating Through Gaseous and Solid Media

“…He also notes that Eq. and atomic hydrogen in gases we give a few of the more comprehensive references: experimental results are contained in reviews by Allison (1958), Allison and Garcia-Munoz (1962), Welsh et al (1967), and in a paper by Toburen et al (1968); theoretical formulations have been presented by Bates and Carroll (1962), Bates (1962), Dalgorno (1964) , Nikolaev (1966) , and Bates and Mapleton (1967).…”

“…Non-additivity of charge changing cross sections in molecular targets It has sometimes been suggested that it may be possible to predict electron capture and loss cross sections in complex molecules simply by adding together the individual cross sections for each atom in the molecule. For example, Toburen et al (1968) and Dagnac et al (1970) have employed such a rule quite successfully for some electron capture and loss cross IV -39 sections of hydrogen projectiles passing through a variety of gases. As theoretical justification of that rule, it has been argued that at high enough velocities of the incident particle the target molecule appears as an assembly of individual atoms whereby the molecular forces are negligible.…”

On the semiclassical impulse approximation for electron capture in asymmetric ion-atom collisions

“…There has been a large number of experiments on total transfer cross sections, most of them concerning proton-hydrogen collisions (see i.e. [1,2] and references quoted therein) and later also heavier systems [3][4][5]. In order to get more insight into the transfer process, also differential cross sections have been measured [6].…”

Theoretical Models for Atomic Charge Transfer in Ion-Atom Collisions

“…3 (p 4-Ar), the impact-parameter dependence at an energy of 6 MeV is depicted in Fig. 2 191 ), x (Berkner et al 192 figure it follows that atomic perturbation models like the transverse peaked SPB in near-shell approximation 31 or the impulse approximation 30 reproduce not only the experimental total cross sections, but also the impact-parameter distribution. The ^-dependence is also well described by the simple Brinkman-Kramers approximation 27 ' 29 although it is (as discussed previously) not an adequate theory, and often overestimates total capture cross sections at the higher energies 164 .…”