Near Infrared Lines as Diagnostics of Accretion in T Tauri Stars
Source: Astrophysics and Space Science, Volume 261, Number 1-4, 1998 , pp. 147-150(4)
Abstract:We present results from a spectroscopic survey of Pa & Br emission in a sample of T Tauri stars, mostly in the Taurus-Auriga complex. Velocity resolved spectra (Δv ∼ 15 km s^-1) show that, of the 41 stars observed in Pa emission, 34% display IPC redshifted absorptions, while, of the 29 stars observed in Br emission, 21% display IPC redshifted absorptions. The lines are broad (FWHM ∼ 200 km s^-1) and lack blueshifted absorptions. These observations are consistent with the near infrared hydrogen lines forming predominantly in infalling material, as suggested by magnetospheric accretion column models. Radiative transfer calculations of the Pa and Br line profiles in a very simplified, spherically symmetric situation are discussed.
Document Type: Regular Paper
Affiliations: 1: Physics Department, Queen Mary & Westfield College London E1 4NS, United Kingdom Centro de Astrofísica da Universidade do Porto Rua do Campo Alegre, 823, 4150 Porto, Portugal 2: Physics Department, Queen Mary & Westfield College London E1 4NS, United Kingdom
Publication date: 1998-01-01