Published November 20, 2011 | Version v1
Journal article

KINEMATICS AND PHYSICAL CONDITIONS OF THE INNERMOST ENVELOPE IN B335

  • 1. Institute of Astrophysics, National Taiwan University, Taipei 10617, Taiwan (China)
  • 2. Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China)

Description

We made C18O (2-1) and CS (7-6) images of the protostellar envelope around B335 with a high spatial dynamic range from ∼10,000 to ∼400 AU by combining the Submillimeter Array and single-dish data. The C18O emission shows an extended (∼10,000 AU) structure as well as a compact (∼1500 AU) component concentrated at the protostellar position. The CS emission shows a compact (∼900 AU) component surrounding the protostar, plus a halo-like (∼3000 AU) structure elongated along the east-west direction. At higher velocities (|ΔV| ∼> 0.3 km s–1), the CS emission is stronger and more extended than the C18O emission. Physical conditions of the envelope were examined through a Large Velocity Gradient model. At |ΔV| ∼> 0.3 km s–1, the gas temperature is higher (>40 K) than that at |ΔV| ∼< 0.3 km s–1, whereas the gas density is lower (<106 cm–3). We consider that the higher temperature and lower density gas at |ΔV| ∼> 0.3 km s–1 is related to the associated outflow, while the lower temperature and higher density gas at |ΔV| ∼< 0.3 km s–1 is the envelope component. From the inspection of the positional offsets in the velocity channel maps, the radial profile of the specific angular momentum of the envelope rotation in B335 was revealed at radii from ∼104 down to ∼102 AU. The specific angular momentum decreases down to a radius of ∼370 AU, and then appears to be conserved within that radius. A possible scenario of the evolution of envelope rotation is discussed.

Availability note (English)

Available from http://dx.doi.org/10.1088/0004-637X/742/1/57

Additional details

Identifiers

Publishing Information

Journal Title
Astrophysical Journal
Journal Volume
742
Journal Issue
1
Journal Page Range
[17 p.]
ISSN
0004-637X
CODEN
ASJOAB

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
43091284
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Descriptors DEI
ANGULAR MOMENTUM; IMAGES; ROTATION; STAR EVOLUTION; STARS
Descriptors DEC
EVOLUTION; MOTION