  Based on the Solar Standard Model SSM of Bahcall and Pinsonneault
(SSM-BP2000) we developed a solar model in hydrostatic equilibrium using three
polytropes, each one associated to the nuclear, the radiative and the
convective regions of the solar interior. Then, we apply small periodic and
adiabatic perturbations on this tri-polytropic model in order to obtain proper
frequencies and proper functions which are in the p-modes range of low order
0<l<5; for l=2,3 and 4 these values agrees with GOLF observational data within
a few percent.
