Application of the Second Born Approximation to Excitation of Hydrogen Atoms by Protons and Antiprotons Impact

We present and compare total cross sections for excitation in collisions of protons and antiprotons with hydrogen atoms in the 2s state. Calculations are performed in the framework of the second Born approximation, in the energy range of 5--1000keV. We apply the usual approach of the second Born approximation, which approximates the summation raised by retaining few terms, as well as another approach approximates all energies corresponding to the intermediate states to that corresponding to the initial state. The annihilation effect in the case of the antiproton collision is investigated. We compare the results with the previous theoretical calculations.