An infall model for the T Tauri phenomenon

Abstract

An infall model which produces P Cygni type II emission lines is presented. The blueshifted apparent absorption feature in these emission lines is interpreted in this model as the overlap region between a strong emission line centered near the rest velocity of the star and a weaker emission line at a velocity near -150 km/s. According to this model the energy source for the continuum and line-emission features observed in T Tauri stars is the kinetic energy of the infalling matter. A weak flux of soft X-rays is produced in the high-temperature postshock gas. These X-rays may be responsible for producing the nebulae observed near some T Tauri stars.