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Detailed Description of J/ApJS/107/281
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Individual files can be fetched (via http) from
here
or via ftp from: ftp://cdsarc.u-strasbg.fr/pub/cats/J/ApJS/107/281
The catalogue can be queried from: http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=J/ApJS/107/281
This standardized document follows the rules of the Standard Description for Astronomical Catalogues. For those having to work on this catalogue using FORTRAN programs, this ReadMe file can be transformed into a f77-compliant program which reads the files making up this catalogue, in two versions: either a f77 program loading whole files into arrays, or a f77-program reading each data file line by line.
J/ApJS/107/281 Atlas of hot, luminous stars at 2 microns (Hanson+ 1996)
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A spectral atlas of hot, luminous stars at 2 microns
Hanson M.M., Conti P.S., Rieke M.J.
<Astrophys. J. Suppl. Ser. 107, 281 (1996)>
=1996ApJS..107..281H
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ADC_Keywords: Stars, luminous ; Spectra, infrared
Keywords: atlases - infrared: stars - stars: early-type -
stars: fundamental parameters
Abstract:
We present 2um (K band) spectra of 180 well-studied, optically
visible, luminous stars. Most of the stars are of OB spectral type,
but we have also included a number of Oe and Be stars, OBN and OBC
stars, cool hypergiant stars, and high-mass X-ray binary stars. Our
aim in studying normal OB stars is to develop an empirical
relationship between 2um spectral features of these massive stars and
their stellar temperature and luminosity. We find the system of lines
between 2.0 and 2.2um is particulary good for differentiating the
early- and mid-O type stars. In the late-O and early-B stars,
differentiation becomes more difficult, as the features show only
moderate changes. We have developed a spectral classification system
for the K band to be used to estimate effective temperatures of O and
early-B stars. We demonstrate that K-band spectroscopy is superior in
estimating the temperature of hot, luminous stars than the traditional
methods of using infrared or even optical photometric colors alone.
The only requirements are that adequate resolution (R>1000) and
signal-to-noise (S/N~70) be achieved. With our classification system,
stars behind large amounts of visible extinction, such as young,
heavily reddened H II regions throughout our Galaxy, may be identified
and studied for the first time through 2um spectroscopy. Emission
lines are commonly seen in the K-band spectra of supergiant stars,
however, the OBN supergiants, which have a higher ratio of some
processed materials at their surface, may be more likely to show line
emission, especially the He I singlet transition at 2.058um. This has
led us to propose an evolutionary scenario for some of the Galactic
center He I emission-line stars, which evokes rotational mixing
(Maeder 1987A&A...178..159M; Langer 1992A&A...265L..17L) to explain
both the strong line emission and high luminosity of these mysterious
sources. We have compared our spectroscopic database with the most
recent stellar atmosphere models. We are encouraged by the good match
between the model line profiles at 2um of Schaerer et al.
(1996A&A...312..475S) and those observed in OB stars. Finally, we
include a thorough discussion of the observational and reduction
methods employed to obtain the spectra shown in this atlas for the
benefit of those wishing to obtain similar, classification-quality,
near-infrared spectra.
File Summary:
FileName Lrecl Records Explanations
× ReadMe 80 . This file
× table1.dat 95 187 Stars in 2 micron spectral atlas
× table1.tex 97 216 AASTeX version of table1.dat
× fits/* 0 . Directory of FITS spectra
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 11 A11 --- Star *Star number
14- 21 A8 --- FITSfile *Eight-character name for data files
24- 39 A16 --- Sp Optical spectral type
40 A1 --- u_Sp A colon indicates Sp is uncertain
42- 44 A3 --- r_Sp *Reference to optical spectral type
47- 52 A6 --- Detector *Detector used for the observation
55- 58 I4 --- SpRes Spectral resolution, Lambda / dLambda
60- 64 A5 "MM/YY" DateObs Date of observation (MM/YY)
66- 78 A13 --- SpK K-band spectral type
81- 95 A15 --- Notes Notes, mostly alternate identifications
Note on Star:
Note that HD 47129 is also known as Plaskett's Star. Bagnuolo, Gies &
Wiggs (1992ApJ...385..708B) show it to be a pair of supergiants.
Note on FITSfile:
The spectrum is stored in FITS format as file:
fits/FITSfile.fit
Note on r_Sp:
Reference to the optical spectral type.
W72 Walborn (1972AJ.....77..312W)
W73 Walborn (1973AJ.....78.1067W)
MT Massey & Thompson (1991AJ....101.1408M)
C74 Conti (1974ApJ...187..539C)
Mth Mathys (1988A&AS...76..427M)
C71 Conti & Alschuler (1971ApJ...170..325C)
W76 Walborn (1976ApJ...205..419W)
M55 Morgan, Code, & Whitford (1955ApJS....2...41M)
WF Walborn & Fitzpatrick (1990PASP..102..379W)
L Lennon, Dufton, & Fitzsimmons (1992A&AS...94..569L)
BS Bright Star Catalogue, Hoffleit (1982, See Cat. V/50)
S SIMBAD database
J93 Jones et al. (1993ApJ...411..323J)
GS Garmany & Stencil (1992A&AS...94..211G)
vP van Paradijs (1994, in X-ray Binaries, ed. Lewin,
van Paradijs & van den Heuvel, p. 536)
HP Howarth & Prinja (1989ApJS...69..527)
G77 Garrison, Hiltner, & Schild (1977ApJS...35..111G)
Note on Detector:
CRSP KPNO Cryogenic Infrared Spectrometer
FSPEC Steward Observatory Infrared Spectrometer
IRS CTIO Infrared Spectrometer
OSIRIS Ohio State Infrared Imaging Spectrometer
Origin: AAS CD-ROM series, Volume 7, 1996 Lee Brotzman [ADS] 09-Oct-96
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(End) Patricia Bauer [CDS] 03-Feb-1997
