DIFFERENTIAL CROSS-SECTIONS FOR ELASTIC-SCATTERING OF ELECTRONS FROM N-2 AT 0.55, 1.5 AND 2.2EV

Differential cross sections for vibrationally elastic scattering of electrons from N2 have been measured at three energies using the relative flow technique and normalizing to the cross sections in helium. At 1.5 eV our results generally support the recent observations of Brennan et al, who find substantially larger cross sections than previously reported by Shyn and Carignan and by Sohn et al. At 0.55 eV, our results are also larger than those of Sohn et al, but in good agreement with the calculations of Morrison et al. A measurement is also reported at the second peak of the 2pi(g) temporary negative ion state, and several difficulties in making comparisons with theory and experiment are elucidated.