CROSS-SECTIONS FOR L-SELECTIVE ELECTRON-CAPTURE INTO THE HE+(N = 4) SHELL IN INTERMEDIATE ENERGY COLLISIONS OF HE2+ WITH H AND H2

This paper shows the extensions of our previous work on absolute cross sections for electron capture into He+(4l) states, produced in collisions of He2+ with atomic and molecular hydrogen, to higher impact energies (27-132 keV amu-1) than used before (2-13 keV amu-1). The cross sections have been deduced from photon emission profile measurements along the ion beam axis, detecting the He II(n = 4 --> n = 3) radiation at a wavelength of 4686 angstrom. The results for collisions with atomic hydrogen generally show reasonable agreement with the atomic orbital calculations of Fritsch below 50 keV amu-1 and at the highest impact energies used (E greater-than-or-equal-to 100 keV amu-1) approach the data of the distorted wave approximation by Belkic et al.