The structure of the NGC1333-IRAS2 protostellar system on 500 AU scales: an infalling envelope, a circumstellar disk, multiple outflows, and chemistry

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

16 pages including figures. Accepted for publication in A&A

Scientific paper

10.1051/0004-6361:20031550

This paper investigates small-scale structures of dense gas and dust around the low-mass protostellar binary NGC1333-IRAS2 using millimeter-wavelength aperture-synthesis observations from the OVRO and BIMA interferometers. The detected 3 mm continuum emission is consistent with models of the envelope around IRAS2A, based on previously reported submillimeter continuum images, down to the 3", or 500 AU, resolution of the interferometer data. Our data constrain the contribution of an unresolved point source to 22 mJy. Within the accuracy of the parameters describing the envelope model, the point source flux has an uncertainty by up to 25%. We interpret this point source as a cold disk of mass \gtrsim 0.3 M_\odot. The same envelope model also reproduces aperture-synthesis line observations of the optically thin isotopic species C34S and H13CO+. The more optically thick main isotope lines show a variety of components in the protostellar environment: N2H+ is closely correlated with dust concentrations as seen at submillimeter wavelengths and is particularly strong toward the starless core IRAS2C. We hypothesize that N2H+ is destroyed through reactions with CO that is released from icy grains near the protostellar sources IRAS2A and B. CS, HCO+, and HCN have complex line shapes apparently affected by both outflow and infall. In addition to the east-west jet from IRAS2A, a north-south velocity gradient near this source indicates a second, perpendicular outflow. This suggests the presence of a binary companion within 0.3" (65 AU) from IRAS2A as driving source of this outflow. Alternative explanations of the velocity gradient such as rotation in a circumstellar envelope or a single, wide-angle outflow are less likely.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The structure of the NGC1333-IRAS2 protostellar system on 500 AU scales: an infalling envelope, a circumstellar disk, multiple outflows, and chemistry does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The structure of the NGC1333-IRAS2 protostellar system on 500 AU scales: an infalling envelope, a circumstellar disk, multiple outflows, and chemistry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The structure of the NGC1333-IRAS2 protostellar system on 500 AU scales: an infalling envelope, a circumstellar disk, multiple outflows, and chemistry will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-478684

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.