|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'506'133
Articles rated: 2609
27 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
The jet and the disk of the HH 212 low-mass protostar imaged by ALMA: SO and SO2 emission | | L. Podio
; C. Codella
; F. Gueth
; S. Cabrit
; R. Bachiller
; A. Gusdorf
; C.-F. Lee
; B. Lefloch
; S. Leurini
; B. Nisini
; M. Tafalla
; | | Date: |
22 May 2015 | | Abstract: | To investigate the disk formation and jet launch in protostars is crucial to
comprehend the earliest stages of star and planet formation. We aim to
constrain the properties of the molecular jet and the disk of the HH 212
protostellar system at unprecedented angular scales through ALMA observations
of sulfur-bearing molecules, SO 9(8)-8(7), SO 10(11)-10(10), SO2 8(2,6)-7(1,7).
SO 9(8)-8(7) and SO2 8(2,6)-7(1,7) show broad velocity profiles. At systemic
velocity they probe the circumstellar gas and the cavity walls. Going from low
to high blue-/red-shifted velocities the emission traces the wide-angle outflow
and the fast (~100-200 km/s) and collimated (~90 AU) molecular jet revealing
the inner knots with timescales <50 years. The jet transports a mass loss rate
>0.2-2e-6 Msun/yr, implying high ejection efficiency (>0.03-0.3). The SO and
SO2 abundances in the jet are ~1e-7-1e-6. SO 10(11)-10(10) emission is compact
and shows small-scale velocity gradients indicating that it originates partly
from the rotating disk previously seen in HCO+ and C17O, and partly from the
base of the jet. The disk mass is >0.002-0.013 Msun, and the SO abundance in
the disk is ~1e-8-1e-7. SO and SO2 are effective tracers of the molecular jet
in the inner few hundreds AU from the protostar. Their abundances indicate that
1% - 40% of sulfur is in SO and SO2 due to shocks in the jet/outflow and/or to
ambipolar diffusion at the wind base. The SO abundance in the disk is 3-4
orders of magnitude larger than in evolved protoplanetary disks. This may be
due to an SO enhancement in the accretion shock at the envelope-disk interface
or in spiral shocks if the disk is partly gravitationally unstable. | | Source: | arXiv, 1505.5919 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER