CROSS SECTIONS FOR CHARGE TRANSFER REACTIONS IN H + O+ AND IN H+ + O COLLISIONS BELOW 10 eV I. Krajcar Bronic1, M. Kimura2, P. C. Stancil3, J.-p. Gu4, G. Hirsch5 and R. J. Buenker4,5=20 1R. Bo=9Akovic Institute, Zagreb, Croatia, 2Yamaguchi University, Japan, 3Oa= k Ridge National Laboratory, USA, 4ITAMP, Harvard-Smithsonian Center for Astrophysics, 5University Wuppertal, Germany Charge transfer in H+ + O and its reverse process, H + O+ collisions, is investigated at low energies below 10 eV based on a fully quantum mechanical molecular orbital expansion model. The two sets of cross sections approach each other above 3 eV and become nearly identical above this energy. A series of very strong oscillatory structures is seen in the energy region between 1.5 eV and 7 eV.