Electron capture, loss and collisional destruction of 5-26 keV metastable and ground-state hydrogen atoms in collisions with atomic and molecular hydrogen

A tungsten-tube furnace containing highly dissociated hydrogen has been used, in conjunction with a previously used technique, to determine cross sections for collisional destruction, electron loss and electron capture by fast hydrogen metastable atoms in atomic hydrogen. Cross sections are not more than about 65% of the corresponding cross sections in H2. While electron loss cross sections for H(2s) atoms are found to be considerably greater than those for H(1s) atoms, corresponding electron capture cross sections are not greatly different. Theoretical estimates of cross sections for collisional destruction and electron loss by H(2s) atoms in H are in poor accord with the present measurements. (author)