Electron capture to the continuum from atomic hydrogen

The differential cross section measurement for electron capture to the continuum (ECC) by 12 MeV C⁶⁺ ion incident on atomic hydrogen 2 ~ 19 cm has been obtained. A value of (4.48+3.2)x10^-19 cm²/sr-atom was found for the differential cross section for an experimental acceptance angle of 2°. The ratio of the ECC differential cross sections for molecular and atomic hydrogen was found to be ~1.25.

The atomic hydrogen target was produced by a high temperature oven which dissociates molecules into H₂ atoms. At a temperature of 2350K, dissociation fractions of >90% were obtained for pressures >3 mTorr in the oven. The oven is electron impact heated by a beam of electrons produced by an electron gun with a Pierce lens system. Design, construction, and operating characteristics of the oven are presented.