We have determined experimental differential cross sections for elastic scattering and the $n=2\mathrm{}$ excitation in ${\mathrm{H}}^{+}$-on-H collisions at an impact energy of 1 keV and compared the results with previous theoretical calculations.

• Received 27 March 1972

DOI:https://doi.org/10.1103/PhysRevLett.28.1433