A study of resonance structures in elastic electron scattering by carbon monoxide and molecular nitrogen in the backward direction

Resonance structures corresponding to the (3s sigma)(2 2)Sigma(+) state in carbon monoxide at 10.044 eV and the (3s sigma(g))(2 2)Sigma(g)(+) state in nitrogen at 11.499 eV have been studied in elastic electron scattering ove r the range of scattering angle from 95 degrees to 180 degrees. A new magne tic angle-changing technique has been used in the measurements, which has e nabled the first observation of these resonance structures at and close to 180 degrees. The width of the (2)Sigma(+) resonance in carbon monoxide has been determined to be 42 +/- 3 meV. (C) 1999 Elsevier Science B.V. All righ ts reserved.