Small-x behaviour of the polarized photon structure function $F_3^\gamma(x,Q^2)$

Abstract

We have studied the formation of ions in collisions of Na(3 d ,5 s ,4 d ) atoms with vibrationally excited Na 2 ( v ”) molecules in their electronic ground state in a supersonic beam. The cross-section of the Na associative ionization is found to be about six times larger than that of the corresponding atomic reaction Na . Associative ionization in collisions of Na(3 d ) with Na 2 ( v ”) is observed only with vibrationally excited Na2 molecules. The cross-section of this reaction increases only slightly with v ” for low vibrational excitation, while a strong increase with v ” is observed for . The latter observation suggests the opening of the channel leading to the formation of ions in the first electronically excited state for .