Two loop partition function in (compactified) heterotic string vacua
J. Atick, A. Sen · OSTI OAI (U.S. Department of Energy Office of Scientific and Technical Information) · 1987
Two loop partition function for the heterotic string theory, compactified on any background preserving space-time supersymmetry at the string tree level, is explicitly calculated. This includes E/sub 8/ x E/sub 8/ or SO(32) heterotic string theory in ten dimensional flat space-time.