Experimental observation of structures in the energy dependence of vibrational excitation in H2by electron impact in the2Σu+resonance region

The energy dependences of the excitation of the vibrational levels nu =1.6 in H 2 by electron impact in the 2 Sigma u + resonance region are reported. Structure due to vibrational motion in the anion, intuitively unexpected for this extremely short-lived resonance, was observed in the excitation of the higher vibrational levels nu =3-5. This result confirms the corresponding recent theoretical predictions of Mundel et al. (1985) based on an advanced treatment of nuclear dynamics in electron scattering.