Charge Exchange Cross Sections of Hydrogen Particles in Gases at High Energies

Abstract

Measurements are reported of the cross section for electron loss (o-0 i) and electron capture (010) for hydrogen atoms and ions traversing gases of hydrogen, helium, nitrogen, and argon. The kinetic energy of the particles was from 250 kev-1 Mev. Cross sections for electron loss were determined by measuring the attenuation of a neutral monatomic hydrogen beam in a gas cell in which a transverse electric field was present. The cross section for electron capture was measured by determining the fraction of the beam in each charge state after passing through a "thick" gas target. The fraction of the neutral component to the charge-one component is equal to the ratio of the cross sections for electron capture to electron loss. The velocity dependence of the cross section does not follow a strict power law. In hydrogen the cross section decreases approximately as v~1 0 , while for heavier target gases the velocity dependence is smaller, being v~3 J for argon at energies greater than 500 kev. The electron loss cross section has a 1/v 2 dependence for gases of hydrogen and helium and a 1/v dependence for nitrogen and argon target gases.

Distorted-wave models for single-electron capture from molecular targets by the impact of bare ions

“…7 Figure 7 also shows twice the total cross section for the atomic reaction H++H( ls) -+H(ls)+H+ in B1B model and it is seen from the figure, by comparison with the molecular 818 results, that the molecular cross section is not just equal to twice the atomic cross section [2,11]. The experimental data are from Barnett and Reynolds [13], Toburen, Nakai, and Langley [14], and Sehryber [15]. The distorted-wave approximations here introduced may be a good starting point to analyze experimental data for heavier projectiles [1].…”

A theoretical model for electron transfer in ion–atom collisions: Calculations for the collision of a proton with an argon atom

“…As a nontrivial application of our method, the electron transfer Experiments: (♦) from [47], ( ) from [52], (•) from [53], ( ) from [54], ( ) from [55], (+) from [56], (×) from [57]. Theory: (•) present results, (lines) from [48] and [50].…”

Observation of the 3He(n,tp) reaction by detection of far-ultraviolet radiation

“…The time spent in a singly ionized state can be obtained simply by interchanging σ 01 ( E ) and σ 10 ( E ). The charge changing cross sections for helium have been measured [15,16] and are given in [13]. The stopping power for protons in helium is well known [17] and the stopping power for tritons can be inferred from the proton data.…”