Electron impact excitation of the low-lying 4s [3/2]1 and 4s'[1/2]1 levels in Ar atom

We report measurements on differential cross sections (DCSs) for electron impact excitation of the low-lying levels, 4s[3/2]1 and 4s'[1/2]1, of the optically-allowed transitions in Ar atom in the electron energy range of 15 – 300 eV. Integral cross sections (ICSs) for these transitions obtained from the measured DCSs are compared with the BEf-scaled Born ICS.