Low-energy and very-low energy total cross sections for electron collisions with N2*
1 Department of Chemistry, Tokyo Institute of Technology, 152-8551 Tokyo, Japan
2 Department of Material and Life Sciences, Sophia University, 102-8554 Tokyo, Japan
Received: 31 January 2017
Received in final form: 7 April 2017
Published online: 6 June 2017
Absolute grand total cross sections for electron scattering from N2 are obtained in the energy range from 20 eV down to 5 meV with very narrow electron energy width of 9 meV using the threshold-photoelectron source. Total cross sections obtained in the present study are compared with the previous experimentally obtained results. At the very-low energy region below 50 meV, the present total cross sections are somewhat smaller than those reported by the Aarhus group [S.V. Hoffmann et al., Rev. Sci. Instrum. 73, 4157 (2002)], which has been the only experimental work that provided the total cross sections in the very-low energy region. The energy positions of the peaks in the total cross sections due to the 2Πg shape resonance are obtained with higher accuracy, due to the improved uncertainty of the energy position in the present measurement compared to the previous works. The resonance structure in the total cross sections due to the Feshbach resonances of N2 at around 11.5 eV are also observed. Analysis of the resonant structure was carried out in order to determine the values of resonance width of Feshbach resonances of N2.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2017