Proton-Impact Excitations between then=2 Fine-Structure Levels of Hydrogenic Ions

Proton impact excitation of the Na atom

“…Using these 2 orbitals, the radial Schrodinger equation is then inverted to obtain l dependent pseudo-potentials for l=0, 1. The use of pseudo-potentials prevents unphysical excitation of the s 1 , s 2 , and p 2 filled subshells during propagation of equation (1).…”

“…In laboratory plasmas proton-impact excitations are known to be important for close lying energy levels, such as those between fine-structure levels of hydrogenic atomic ions [1]. It is expected that proton-impact collisions will be important in solar flares, where very high energy and dynamic conditions exist [2].…”

Annihilation cross section of protonium by electron impact

“…But it does not hold for d and f states, since the electron mass is small, and some low-lying partial waves determine their cross sections. This is in contrast to ion impact, where, except at very low collisions, much more partial waves contribute to the cross section even for optically forbidden transitions [40]. where the calculation has been simplified [30,43] owing to the orthogonality relations of the Clebsch-Gordan coefficients, Y lm and Y J M l , appear in (A.11) and (A.12), and to the relations used for (A.10).…”

“…Quite large partial waves might have to be involved for the annihilation from p states at high energies since ns in (1) is small. For such a reason, we have used the semiclassical treatment called the common trajectory method [38][39][40], which becomes effective for higher collision energies and for larger partial waves.…”