Astrophysics and Space Science

, Volume 212, Issue 1–2, pp 139–145 | Cite as

Identification of a collapsing protostar

  • Neal J. EvansII
  • Shudong Zhou
  • Carsten Kömpe
  • C. M. Walmsley
Article

Abstract

The globular molecular cloud B335 contains a single, deeply embedded, far-infrared source. Our recent observations of H2CO and CS lines toward this source provide direct kinematic evidence for collapse. Both the intensity and detailed shape of the line profiles match those expected from inside-out collapse inside a radius of 0.036 pc. The collapse began about 1.5 × 105 years ago, similar to the onset of the outflow. The mass accretion rate is about 10 times the outflow rate, and about 0.4M should have now accumulated in the star and disk. Because B335 rotates only very slowly, any disk would still be very small (about 3 AU). The accretion luminosity should be adequate to power the observed luminosity. Consequently, we believe that B335 is indeed a collapsing protostar.

Keywords

Recent Observation Line Profile Accretion Rate H2CO Molecular Cloud 

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Copyright information

© Kluwer Academic Publishers 1994

Authors and Affiliations

  • Neal J. EvansII
    • 1
  • Shudong Zhou
    • 2
  • Carsten Kömpe
    • 3
  • C. M. Walmsley
    • 3
  1. 1.Department of AstronomyThe University of Texas at AustinAustinUSA
  2. 2.Department of AstronomyUniversity of IllinoisUrbanaUSA
  3. 3.Max-Planck-Institut für RadioastronomieBonnGermany

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