ELECTROMAGNETIC INDUCTION-HEATING OF METEORITE PARENT BODIES BY THE PRIMORDIAL SOLAR-WIND

We consider the electromagnetic induction heating of meteorite parent bodies in the strong solar wind in the T Tauri phase of the Sun including the effect of the Alfven wing generated by the interaction between a steady uniformly flowing magnetized plasma and a conductor. The characteristics of the electric current induced in the conductor are determined by the shortest of the three characteristic times: time for the Alfven wave to propagate from one boundary of the conductor to the other (Alfven travel time), time for the flow to cross the conductor, and time for the conductor to diffuse the magnetic field. The limit for which the Alfven travel time is the shortest is applied to the interaction between a meteorite parent body and the solar wind in the T Tauri phase. In this limit the increase of the temperature of meteorite parent bodies is independent of the magnetic field, and inversely proportional to the electrical conductivity of meteorite parent bodies. Numerical calculations are carried out in the case where the electrical conductivity depends on the temperature. The result shows that the region of the high heating rate is confined to the surface. Since the conductivity has a strong positive dependence on the temperature, negative feedback on the heating process tends to suppress the temperature increase. The result also indicates that the lower the surface temperature, the higher the heating rate, since the conductivity is kept low.