A Brγ Probe of Disk Accretion in T Tauri Stars and Embedded Young Stellar Objects

Abstract

We report on observations of Pab and Brc for a sample of classical T Tauri stars in Taurus and nd a tight correlation between the emission-line luminosities and the accretion luminosity as measured from the hot continuum excess. We use the Brc luminosity correlation to calculate accretion luminosities in highly reddened young stars with existing line measurements. The distribution of accretion luminosities is similar in Taurus and Ophiuchus Class II sources. For the deeply embedded Class I objects, the accretion luminosities are in general less than the bolometric luminosities, which implies that the disk accretion rates are signicantly lower than the envelope infall rates. We nd that the central sources of many Class I objects are quite similar to their Class II counterparts.