|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'504'928
Articles rated: 2609
25 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
A low-mass protostar's disk-envelope interface: disk-shadowing evidence from ALMA DCO+ observations of VLA1623 | | Nadia M. Murillo
; Simon Bruderer
; Ewine F. van Dishoeck
; Catherine Walsh
; Daniel Harsono
; Shih-Ping Lai
; Christian M. Fuchs
; | | Date: |
28 May 2015 | | Abstract: | Due to instrumental limitations and a lack of disk detections, the structure
between the envelope and the rotationally supported disk has been poorly
studied. This is now possible with ALMA through observations of CO isotopologs
and tracers of freezeout. Class 0 sources are ideal for such studies given
their almost intact envelope and young disk. The structure of the disk-envelope
interface of the prototypical Class 0 source, VLA1623A which has a confirmed
Keplerian disk, is constrained from ALMA observations of DCO+ 3-2 and C18O 2-1.
The physical structure of VLA1623 is obtained from the large-scale SED and
continuum radiative transfer. An analytic model using a simple network coupled
with radial density and temperature profiles is used as input for a 2D line
radiative transfer calculation for comparison with the ALMA Cycle 0 12m array
and Cycle 2 ACA observations of VLA1623. DCO+ emission shows a clumpy structure
bordering VLA1623A’s Keplerian disk, suggesting a cold ring-like structure at
the disk-envelope interface. The radial position of the observed DCO+ peak is
reproduced in our model only if the region’s temperature is between 11-16K,
lower than expected from models constrained by continuum and SED. Altering the
density has little effect on the DCO+ position, but increased density is needed
to reproduce the disk traced in C18O. The DCO+ emission around VLA1623A is the
product of shadowing of the envelope by the disk. Disk-shadowing causes a drop
in the gas temperature outside of the disk on >200AU scales, encouraging
deuterated molecule production. This indicates that the physical structure of
the disk-envelope interface differs from the rest of the envelope, highlighting
the drastic impact that the disk has on the envelope and temperature structure.
The results presented here show that DCO+ is an excellent cold temperature
tracer. | | Source: | arXiv, 1505.7761 | | 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