2005A&A...433.1101W


C.D.S. - SIMBAD4 rel 1.7 - 2021.02.26CET18:19:43

2005A&A...433.1101W - Astronomy and Astrophysics, volume 433, 1101-1115 (2005/4-3)

Dust cloud formation in stellar environments. II. Two-dimensional models for structure formation around AGB stars.

WOITKE P. and NICCOLINI G.

Abstract (from CDS):

This paper reports on computational evidence for the formation of cloud-like dust structures around C-rich AGB stars. This spatio-temporal structure formation process is caused by a radiative/thermal instability of dust-forming gases as identified by Woitke et al. (2000A&A...358..665W). Our 2D (axisymmetric) models combine a time-dependent description of the dust formation process according to Gail & Sedlmayr (1988A&A...206..153G) with detailed, frequency-dependent continuum radiative transfer by means of a Monte Carlo method (Niccolini et al., 2003A&A...399..703N) in an otherwise static medium (v=0). These models show that the formation of dust behind already condensed regions, which shield the stellar radiation field, is strongly favoured. In the shadow of these clouds the temperature decreases by several hundred Kelvin, which triggers the subsequent formation of dust and ensures its thermal stability. Considering an initially dust-free gas with small density inhomogeneities, we find that finger-like dust structures develop which are cooler than the surroundings and point towards the centre of the radiant emission, similar to the ``cometary knots'' observed in planetary nebulae and star formation regions. Compared to a spherical symmetric reference model, the clumpy dust distribution has little effect on the spectral energy distribution, but dominates the optical appearance in near IR monochromatic images.

Abstract Copyright:

Journal keyword(s): instabilities - radiative transfer - ISM: dust, extinction - stars: AGB and post-AGB - stars: circumstellar matter - stars: mass-loss

Simbad objects: 10

goto Full paper

goto View the reference in ADS

Number of rows : 10

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 V* TX Cam Mi* 05 00 51.1569959503 +56 10 54.093107078       14.02   M9-9.5 333 0
2 M 42 HII 05 35 17.3 -05 23 28           ~ 3776 0
3 * alf Ori s*r 05 55 10.30536 +07 24 25.4304 4.38 2.27 0.42 -1.17 -2.45 M1-M2Ia-Iab 1509 0
4 * L02 Pup AB* 07 13 32.3181035 -44 38 23.062946 7.90 6.66 5.10 2.49 0.07 M5IIIe 198 0
5 NGC 2392 PN 07 29 10.7669120392 +20 54 42.478515772     9.68     O6f 700 1
6 IRC +10216 C* 09 47 57.40632 +13 16 43.5648     10.96     C9,5e 2177 0
7 WOS 48 C* 15 23 05.0744336371 -51 25 58.881494593   17.85 16.66 14.51 10.18 C 121 1
8 V* TT Cyg C* 19 40 57.0159854799 +32 37 05.755486755   10.43 10.20     C-N5- 190 0
9 NGC 7293 PN 22 29 38.5453078023 -20 50 13.746093105 11.894 13.158 13.524 13.689 13.898 DAO.5 907 0
10 * 19 Psc C* 23 46 23.5126056542 +03 29 12.505415198 10.95 7.62 5.02 3.19 1.82 C-N6 434 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2005A&A...433.1101W and select 'bookmark this link' or equivalent in the popup menu


2021.02.26-18:19:43

© Université de Strasbourg/CNRS

    • Contact