Semi-empirical cross sections for excitation of hydrogen atoms by protons

Results obtained by quantal, semiclassical and classical theories are combined with results of experiment to obtain estimates of averaged n to n' excitation cross sections for all initial and final energy levels n and n' and for non-relativistic incident proton energies E greater than 30 keV or (100/n 2 ) keV, whichever is the less. A semi-empirical cross section which is an analytic function of E, n, n' has estimated errors normally of the order of 20% or better.