DIFFERENTIAL ELECTRON-SCATTERING FROM ACETYLENE ELASTIC-SCATTERING AND VIBRATIONAL-EXCITATION

Absolute differential cross sections for elastic scattering of electro ns from acetylene are reported. The relative flow method was applied t o normalize these cross sections, using helium as a standard. The meas urements were made at the incident electron energies of 5 eV, 10 eV, 1 5 eV, 20 eV, 30 eV, 50 eV and 100 eV for electron scattering angles in the range of 10 degrees to 125 degrees. In addition, we report differ ential cross sections for excitation of the upsilon(1)/upsilon(3) (unr esolved); upsilon(2), upsilon(4)/upsilon(5) (unresolved) and upsilon(4 ) + upsilon(5) vibrational modes of acetylene at 5 eV and 10 eV incide nt electron energies for scattering angles in the range of 20 degrees to 120 degrees. From these results integral cross sections are derived and the present results are compared with other available experimenta l and theoretical cross sections.