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Physical Review A

Isotopic velocity-dependent effects in He+ + H2 or D2 collisions

D. H. Jaecks

Published Feb 1, 1988• 3 citations
Publisher

Abstract

Isotope shifts have been measured in the velocity-dependent total cross sections of the ${m}_{1}$=1 magnetic substate of He(3 $^{3}$P) formed in low keV ${\mathrm{He}}^{+}$+${\mathrm{H}}_{2}$ or ${\mathrm{D}}_{2}$ collisions. Similar isotope shifts have been predicted on theoretical grounds and observed in ion-atom collision experiments, where united-atom rotational coupling is the primary excitation mechanism. By extending the basic theoretical ideas to ion-molecule collisions, we can interpret our measured shifts as resulting from rotational coupling within the triatomic ${\mathrm{HeH}}_{2}^{+}$ complex.

DOI
10.1103/physreva.37.1041

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