The middle-high degree adiabatic p-mode eigenfrequencies of the solar envelope models

Abstract

In this paper, the adiabatic p-mode eigenfrequencies for five solar convective envelope models are calculated, using Xiong's nonlocal convection theory. At the precision level of one percent, they are well consistent with observation. From the plotting of Δν(= ν obs − ν cal) vs. ν, it is obvious for the models with smaller convection parameter c 1 (the models I and II), that the frequency differences fall into two distinct groups. For the modes with l > 60, the differencies decrease as the frequency increases, distributing in an inclined narrow strip. This indicates that the main error source is located in the out- ermost 5% R ⊙ region of the models, possibly due to the nonadiabatic effects and the uncertainty in the equation of state. For the modes with l ⩽ 60, the theoretical eigenfrequencies are systematically smaller than the observed ones, implying that another error source locates at the bottom of the solar convection zone and the overshooting region below. It may be most likely interpreted by the existence of a magnetic field of 10 3– 10 4 gauss in the lower part of the solar convection zone.