Electron Capture in Collisions between Protons and Hydrogen Atoms

Cross sections are being determined for electron transfer and other processes in intermediate (keV)- energy $p$-H collisions using a double-center Sturmian basis, substantially expanding pioneering Sturmian calculations carried out thirty years ago.\footnote{R.Shakeshaft, J. Phys. B {\bf 8}, 1114 (1975); Phys. Rev. A {\bf 18}, 1930 (1978).} The computer code for arbitrary nuclear charges, recently applied to $\alpha$-H collisons, \footnote {T.G. Winter, Phys. Rev. A {\bf 76}, 062702 (2007).} is being specialized to the homonuclear case to reduce the number of distinct matrix elements and the number of coupled channels. The results may be compared with large basis, double-center Gaussian results\footnote{N. Toshima, Phys. Rev. A {\bf 59}, 1981 (1999).}; triple-center results\footnote{T. G. Winter and C.D. Lin, Phys. Rev. A {\bf 29}, 567 (1984).}; double-center, even-tempered basis results\footnote{J. Kuang and C. D. Lin, J. Phys. B {\bf 29}, 1207 (1996).}; other theoretical results; and numerous experimental results.\footnote{See T. G. Winter, Adv. At., Mol., Opt. Phys. {\bf 52}, 391 (2005).}