Evidence for HCO^+ infall toward T Tauri?

Abstract

High spectral and spatial resolution observations of the HCO^+ molecule toward the T Tau binary system obtained with the Owens Valley Millimeter Array reveal a broad emission line profile (V_(LSR) = 7.2 km s^(-1), ΔV = 2.0 km s^(-1)) upon which a narrow, redshifted absorption feature (V_(LSR) = 8.5 km s^(-1), ΔV ≈ 0.5 km s^(-1)) is superposed. One possible interpretation of the absorption is that it rises from infall of molecular cloud envelope material onto the immediate circumbinary region, which would imply that large-scale dynamic accretion processes are still active well into the optically visible stages of star formation. Provided the mass is deposited at radii sufficiently close to the young stars, estimates of the accretion rates indicate that infall may add enough material to the system to account for the FU Orionis type flares recently observed in T Tau in ≾ 100 yr.

Additional Information

© 1994 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1993 December 14; accepted 1994 January 25. The authors would like to thank the JCMT, IRAM, and OVRO staff. OVRO is operated under funding from the NSF, contract 90-16404. Frank Helmich is thanked for carrying out the JCMT observations. E. vD. and H. J. vL. acknowledge support from the Netherlands Organization for Scientific Research (NWO), and G. A. B. from the David and Lucille Packard and Alfred P. Sloan Foundations, as well as NASA grant NAGW-2297.

Attached Files

Published - VanLangevelde_Astrophys1994pL45.pdf

Files

Additional details