VI/125 Theoretical spectra of red giants and supergiants (Lancon+, 2007)
Near-IR spectra of red supergiants and giants.
I- Models with solar and with mixing-induced surface abundance ratios.
Lancon A., Hauschildt P.H., Ladjal D., Mouhcine M.
<Astron. Astrophys. 468, 205 (2007)>
=2007A&A...468..205L 2007A&A...468..205L
ADC_Keywords: Stars, giant ; Stars, supergiant ; Spectra, infrared ; Models
Keywords: stars: fundamental parameters - stars: abundances - infrared: stars -
stars: atmospheres
Abstract:
It remains difficult to interpret the near-IR emission of young
stellar populations. One main reason is our incomplete understanding
of the spectra of luminous red stars. This work provides a grid of
theoretical spectra of red giant (RG) and red supergiant (RSG) stars,
that extends through optical and near-IR wavelengths. For the first
time, models are also provided with modified surface abundances of C,
N and O, as a step towards accounting for the changes that occur due
to convective dredge-up in red supergiants or may occur at earlier
evolutionary stages in the case of rotation. The aims are (i) to
assess how well current models reproduce observed spectra, in
particular in the near-IR; (ii) to quantify the effects of the
abundance changes on the spectra; and (iii) to determine how these
changes affect estimates of fundamental stellar parameters.
Description:
Each FITS file in this directory contains a theoretical stellar
spectrum. The spherical model atmospheres and the synthetic spectra
were computed with PHOENIX version 13.11.00B as described in the
article, with an initial wavelength sampling step of 0.01nm in the
wavelength range of interest [510nm-2490nm]. The spectra made
available here have been smoothed with a Gaussian with a full width
at half maximum of 0.2nm. They are resampled with a wavelength step
of 0.025nm.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 56 403 List of the spectra
m15rsg/* . 142 RSG-specific abundances, M=15M☉ model spectra
m15solar/* . 140 Solar abundances, M=15M☉ model spectra
m1solar/* . 121 Solar abundances, M=1M☉ model spectra
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Description of files:
Fundamental model parameters can be extracted from the filename and
are repeated in self-explanatory header keywords.
* lteTTgpG.GmMM_solar.fits lteTTgpG.GmMM_RSG.fits
contains the spectrum for a star of mass MM (in solar masses),
of effective temperature TT*100 (in Kelvin),
and of log(g) G.G (in cm/s2),
computed with solar (left) or with RSG-specific (right) abundances.
* lteTTgmG.GmMM_solar.fits lteTTgmG.GmMM_RSG.fits
contains the spectrum with parameters as above except that
log(g) is -G.G (in cm/s2).
The header keyword BUNIT recalls the flux units : erg/s/cm2/cm.
Summary of the models provided :
M = 1 M(sun), solar abundances : Teff in [2900K-5900K] in steps of 100K
log(g) in {-1,-0.5,0,1,2}
M = 15 M(sun), solar abundances : Teff in [2900K-5900K] in steps of 100K
log(g) in {-1,-0.5,0,1,2}
M = 15 M(sun), RSG-specific abundances :
Teff in [2900K-5900K] in steps of 100K
log(g) in {-1,-0.5,0,1,2}
See also:
III/196 : Near-IR stellar spectra from 1.428 to 2.5 um (Lancon+ 1996)
J/A+AS/146/217 : Library of 0.5-2um spectra of Cool Stars (Lancon+ 2000)
J/A+A/393/167 : Mean Spectra for upper AGB stars (Lancon+, 2002)
J/A+A/405/531 : IR spectra of ISOGAL sources in Bulge (Schultheis+ 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Model Model (m15rsg, m15solar or m1solar)
10- 11 I2 solMass Mass Mass
13- 16 I4 K Teff Effective temperature
18- 21 F4.1 [cm/s2] logg Surface gravity
24- 56 A33 --- FileName Name of the fits file
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Acknowledgements:
Ariane Lancon, ariane.lancon(at)astro.u-strasbg.fr
(End) Ariane Lancon [Observatoire de Strasbourg] 13-Feb-2007