Emission-line widths and stellar-wind flows in T Tauri stars

Abstract

We report on spectra of T Tauri stars taken with the IPCS on the Isaac Newton Telescope at the Observatorio del Roque de los Muchachos at a dispersion of 17 Å mm−1. These were taken in order to determine emission-line widths and hence flow velocities in the winds of these stars following the successful modelling of the wind from RU Lupi using such data. Line widths in RW Aur suggest a similar pattern to the wind flow as in RU Lupi with velocities rising in the inner chromosphere of the star and then entering a ‘ballistic’ zone. The wind from DF Tau is also similar but velocities are generally much lower and the lines sharper. The pattern may also be the same in V380 Ori but in DI Cep, on the other hand, the wind also accelerates in the outer chromosphere with He Iλ5876 Å being the broadest line.