Low Energy Phenomena in a Model With Symmetry Group SUSY SO(10) X Delta (48) X U(1)

Fermion masses and mixing angles including that of neutrinos are studied in a model with symmetry group SUSY $SO(10)\times \Delta (48) \times U(1)$. Universality of Yukawa coupling of superfields is assumed. The resulting texture of mass matrices in the low energy region depends only on a single coupling constant and VEVs caused by necessary symmetry breaking. 13 parameters involving masses and mixing angles in the quark and charged lepton sector are successfully described by only five parameters with two of them determined by the scales of U(1), SO(10) and SU(5) symmetry breaking compatible with the requirement of grand unification and proton decay. The neutrino masses and mixing angles in the leptonic sector are also determined with the addition of a Majorana coupling term. It is found that LSND $\bar{\nu}_{\mu}\rightarrow \bar{\nu}_{e}$ events, atmospheric neutrino deficit and the mass limit put by hot dark matter can be naturally explained. Solar neutrino puzzle can be solved only by introducing sterile neutrino with one additional parameter. More precise measurements of $\alpha_{s}(M_{Z})$, $V_{cb}$, $V_{ub}/V_{cb}$, $m_{b}$, $m_{t}$, as well as various CP violation and neutrino oscillation experiments will provide crucial tests of the present model.