Electron transfer in collisions of keV hydrogen atoms and ions with methane

Absolute differential cross sections are reported for electron capture and loss by 1-5 keV H atoms incident on CH4 for laboratory scattering angles up to 1.62 degrees, and for charge transfer of 0.5-5 keV H+ with CH4 for scattering angles up to 2.09 degrees. Electron-loss collisions are seen to result in comparatively large scattering angles and a very clear similarity exists between the present differential cross sections and those reported for other molecular targets. The present charge-transfer differential cross sections are consistent with that of Gao et al (1990 Phys. Rev. A 41 5929-33) but not with the calculations of Kimura et al (1995 Phys. Rev. A 52 1196-205). Prior experimental studies of electron-loss and charge-transfer are generally in good accord with the integral values reported here as are the calculations of Kusakabe et al.