This proposed research is a continuation of the previous investigations on excitation cross section measurement of molecular oxygen by electron impact for Pseudo-continuum region (4 - 7 eV energy loss) and an extensive data analysis of Schumann-Runge region ( 7 - 10 eV energy -loss). This experimental and theoretical joint research program will determine absolute electron impact cross sections for all the important electronic transitions of molecular oxygen in the 4 - 10 eV energy loss region. Differential cross sections of identifiabled electronic states and vibrational excitations of electronic states will be measured by a crossed-beam method over angles ranging from 12 to 160o with impact energies ranging from near threshold to 200 eV. From the observed electron impact process, the dissociation products will be identified by a detailed analysis of the combined photoabsorption and electron energy-loss data for the dissociation of O2 into ground and excited stated atomic fragments ( O(1D), O(1S)). These results will be analyzed by an extensive configuration interaction calculation, performed at Los Alamos National Laboratory in order to obtain potential energy curves and dipole electronic transition moments from the ground state to the excited states.