Possible candidates for a supersymmetric SO(10) model with an intermediate scale

Abstract
We study the possibility of an intermediate scale existing in supersymmetric SO(10) grand unified theories. The intermediate scale is required to be around 1012 GeV so that neutrinos can obtain masses suitable for explaining the experimental data on the deficit of solar neutrinos with the Mikheyev-Smirnov-Wolfenstein solution and the existence of hot dark matter. We show that any Pati-Salam-type intermediate symmetries are excluded by requiring reasonable conditions and only SU(2)L×SU(2)R×SU(3)C×U(1)BL is likely to be realized as an intermediate symmetry.