2008A&A...478..543Z


Query : 2008A&A...478..543Z

2008A&A...478..543Z - Astronomy and Astrophysics, volume 478, 543-551 (2008/2-1)

Axi-symmetric models of B[e] supergiants. I. The effective temperature and mass-loss dependence of the hydrogen and helium ionization structure.

ZSARGO J., HILLIER D.J. and GEORGIEV L.N.

Abstract (from CDS):

We calculate the hydrogen and helium ionization in B[e] envelopes and explore their dependence on mass-loss and effective temperature. We also present simulated observations of the Hα emission line and the CIV λλ1550 doublet, and study their behavior. This paper reports our first results in an ongoing study of B[e] supergiants, and provides a glimpse on the ionization of the most important elements in self-consistent numerical simulations. Our newly developed 2D stellar atmosphere code, ASTAROTH, was used for the numerical simulations. The code self-consistently solves for the continuum radiation, non-LTE level populations, and electron temperature in axi-symmetric stellar envelopes. Observed profiles were calculated by an auxiliary program developed separately from ASTAROTH. In all but one of our models, H remained fully ionized - only for {dot}(M)>10–5M/yr and Teff≤18000K did we obtain a neutral H disk, and then only for radii beyond 3R*. Due to ionizations from excited states it is much more difficult to get a H neutral disk than indicated by previous analytical calculations. Near the poles, the ionization is high in all models, while helium recombined in the equatorial regions for all but our lowest mass-loss rate (10–6M/yr). Although the model parameters were not adjusted to provide fits to any particular star, the theoretical profiles show some features seen in the profiles of R126. These include the partially resolved double peaked profile of Hα, and the weak emission associated with the UV CIV resonance line.

Abstract Copyright:

Journal keyword(s): radiative transfer - atomic processes - stars: early-type - stars: winds, outflows

Simbad objects: 9

goto Full paper

goto View the references in ADS

Number of rows : 9
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 NAME SMC G 00 52 38.0 -72 48 01   2.79 2.2     ~ 10242 1
2 NAME Magellanic Clouds GrG 03 00 -71.0           ~ 6308 1
3 NAME LMC G 05 23 34.6 -69 45 22     0.4     ~ 16049 1
4 HD 37974 s*b 05 36 25.8534763728 -69 22 55.789571064 10.056 11.12 10.99 11.00 10.423 B0.5e 118 0
5 * zet Pup BY* 08 03 35.04754 -40 00 11.3321 0.89 1.98 2.25 2.36 2.58 O4I(n)fp 1125 1
6 NAME Homunculus Nebula ISM 10 45 03.5 -59 41 04           ~ 345 1
7 * eta Car Em* 10 45 03.5377808928 -59 41 04.051599720 6.37 7.03 6.48 4.90 4.41 OBepec 2328 0
8 V* AG Car WR* 10 56 11.5781414448 -60 27 12.810673260 7.00 7.57 6.96 7.73   WN11h 613 0
9 * P Cyg s*b 20 17 47.2020844 +38 01 58.552724 4.66 5.24 4.82 4.28 4.02 B1-2Ia-0ep 1153 1

To bookmark this query, right click on this link: simbad:objects in 2008A&A...478..543Z and select 'bookmark this link' or equivalent in the popup menu


2022.06.27-19:40:42

© Université de Strasbourg/CNRS

    • Contact