2004A&A...413..241W


Query : 2004A&A...413..241W

2004A&A...413..241W - Astronomy and Astrophysics, volume 413, 241-249 (2004/1-1)

Australia Telescope Compact Array imaging of circumstellar HCN line emission from R Scl.

WONG T., SCHOEIER F.L., LINDQVIST M. and OLOFSSON H.

Abstract (from CDS):

We present radio-interferometric observations of HCN J=1->0 line emission from the carbon star R Scl, obtained with the interim 3-mm receivers of the Australia Telescope Compact Array. The emission is resolved into a central source with a Gaussian FWHM of ∼1", which we identify as the present mass loss envelope. Using a simple photodissociation model and constraints from single-dish HCN spectra, we argue that the present mass-loss rate is low, ∼2x10–7M/yr, supporting the idea that R Scl had to experience a brief episode of intense mass loss in order to produce the detached CO shell at ∼10" radius inferred from single-dish observations. Detailed radiative transfer modelling yields an abundance of HCN relative to H2, fHCN, of ∼10–5 in the present-day wind. There appears to be a discrepancy between model results obtained with higher transition single-dish data included and those from the J=1->0 interferometer data alone, in that the interferometer data suggest a smaller envelope size and larger HCN abundance than the single-dish data. The lack of HCN in the detached shell, fHCN≲2x10–7, is consistent with the rapid photodissociation of HCN into CN as it expands away from the star.

Abstract Copyright:

Journal keyword(s): circumstellar matter - stars: carbon - stars: AGB and post-AGB - stars: mass-loss

Simbad objects: 11

goto Full paper

goto View the references in ADS

Number of rows : 11
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2022
#notes
1 QSO B0104-408 QSO 01 06 45.1074148680 -40 34 19.954747560   18.60 19.0 19.25   ~ 126 0
2 V* R Scl C* 01 26 58.0939182720 -32 32 35.439234828 17.26 9.59 5.72 3.69 2.30 C-N5+ 315 0
3 QSO B0208-512 BLL 02 10 46.2004407600 -51 01 01.893013392   17.10 16.93 14.82   ~ 411 1
4 V* U Cam C* 03 41 48.1758504744 +62 38 54.395692404   11.5 11.00     C-N5 238 0
5 QSO B0420-0127 QSO 04 23 15.8007747432 -01 20 33.063518580   17.50 17.00 16.28   ~ 1134 3
6 IRC +10216 C* 09 47 57.40632 +13 16 43.5648     10.96     C9,5e 2246 0
7 V* U Ant C* 10 35 12.8510147472 -39 33 45.324020448 15.32 8.22 5.38 3.18 1.86 C-N3 142 0
8 V* S Sct C* 18 50 20.0367791256 -07 54 27.429169356 13.93 9.89 6.80     C-N5 202 0
9 QSO B1921-293 BLL 19 24 51.0555700728 -29 14 30.118109640   18.71 18.21 15.07   ~ 776 0
10 V* TT Cyg C* 19 40 57.0158460384 +32 37 05.756696400   10.43 10.20     C-N5- 195 0
11 ICRF J225805.9-275821 Sy1 22 58 05.9627218728 -27 58 21.258376248   17.34 16.77 17.20   ~ 324 1

To bookmark this query, right click on this link: simbad:objects in 2004A&A...413..241W and select 'bookmark this link' or equivalent in the popup menu


2022.08.09-03:57:28

© Université de Strasbourg/CNRS

    • Contact