III/166 A New Library of Optical Spectra (Silva + 1992)
A New Library of Stellar Optical Spectra
Silva D.R., Cornell M.E.
<Astrophys. J. Suppl. 81, 865 (1992)>
=1992ApJS...81..865S 1992ApJS...81..865S
ADC_Keywords: Spectrophotometry ; Spectral types
Abstract:
Silva and Cornell have compiled a new digital optical stellar spectra
library, consisting of intensities at 5A intervals between 3510A and
8930A for 72 different spectral types. These types range from O to M
and luminosities range from I to V. Some weak-line and strong-line
spectra are also included. The intensities are in ergs/A, normalized
to 100 at 5450A.
Description:
Newly acquired and previously published data have been combined to
form a new digital optical library intended primarily for use in
empirical population synthesis. Stellar data for a large number of
individual stars were acquired during seven observing runs between
December 1988 and May 1989. An effort was made to observe, primarily,
stars with TZG parameters derived from stellar atmosphere models of
high dispersion data. Observations of photometric calibration stars
were made during each run, but absolute calibrations were not
attempted.
Composite spectra from different observations of each star were formed
by multiplicatively scaling the individual sub-spectra and averaging.
The resultant composite spectra were normalized to 100 at 5450A. Next,
the effects of interstellar reddening were removed. Intensities in the
spectral regions most affected by telluric absorption were set to
zero. Finally, stars with similar TZG parameters and similar overall
spectral characteristics were averaged to form the individual spectra
in the library, also normalized to 100 at 5450A. Table 1 lists the
individual types averaged to form each of the 72 entries in the
catalog. The prefixes R and W refer to strong- and weak-line stars,
respectively.
The list of the observed stars (Table 2 of the paper), and the
synthesized UBV colors (Tables 3 and 4 of the paper) were added to the
electronic catalog in 1999.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 91 151 *List of stars observed (Table 2)
spectra.dat 54 72 *Composite library spectra: Synthesized versus
Catalog UBV colours (Tables 3 and 4)
sp/* . 72 The synthetic spectra (1 file per spectrum)
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Note on stars.dat, spectra.dat:
Two stars quoted in Table 3 of the paper are not in file stars.dat:
242935 (in spectral class O7B0V)
g137-69 (in wG8-K0)
Three stars in file stars.dat are not used in spectra.dat:
236894 (O8V)
115043 (G1Va)
s84091 (K0V)
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Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- SpNo [1,72]? Spectrum number
4- 5 I2 h RAh *Right Ascension J2000 (hours)
7- 8 I2 min RAm *Right Ascension J2000 (minutes)
10- 13 F4.1 s RAs *Right Ascension J2000 (seconds)
15 A1 --- DE- *Declination J2000 (sign)
16- 17 I2 deg DEd *Declination J2000 (degrees)
19- 20 I2 arcmin DEm *Declination J2000 (minutes)
22- 23 I2 arcsec DEs *Declination J2000 (seconds)
25- 30 I6 --- HD ? HD designation of the star
33- 39 A7 --- Other *Other designation
42- 50 A9 --- Sp *MK Spectral class
52- 61 A10 --- Obs *[AC-K.] Observations flags
64- 68 I5 K Teff Effective temperature
71 I1 --- L Assigned luminosity class
73- 74 I2 --- M *[-1,1] Assigned metallicity class
76- 80 F5.2 [Sun] [Fe/H] Metallicity index
83- 86 F4.2 mag E(B-V) Colour excess
88- 91 A4 --- Ref *Reference
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Note on RAh, RAm, RAs, DE-, DEd, DEm, DEs:
position from SIMBAD data-base
Note on Other: the designation starts by "s" for SAO (Cat. I/131)
designations, or by "g" for Giclas et al. Lowell Proper Motion stars.
Note on Sp: Spectral class from original reference. Stars from reference
L (1988AJ.....95.1843L 1988AJ.....95.1843L) and marked V* are most likely dwarfs, but could
be some other luminosity class.
Note on Obs: Observation codes are:
A = MDM 2.4m 1988Jan, MkIII spectrograph, G4 grism
C = MDM 2.4m 1988Feb, MkIII spectrograph, G4 grism
D = SOKP 2.3m 1988Mar, B&C spectrograph
E = SOKP 2.3m 1988May, B&C spectrograph
F = MDM 2.4m 1988Nov, MkIII spectrograph, G2 grism
G = MDM 2.4m 1988Nov, MkIII spectrograph, G4 grism
H = MDM 2.4m 1989Feb, MkIII spectrograph, G4 grism
I = MDM 2.4m 1989Feb, MkIII spectrograph, G2 grism
J = MDM 2.4m 1989May, MkIII spectrograph, G4 grism
K = MDM 2.4m 1989May, MkIII spectrograph, G2 grism
where MDM designates Michigan-Dartmouth-MIT, spectral regime:
G2 = 675-925nm, G4 = 436-710nm
and SOKP designates Stewart Obs. Kitt Peak, spectral regime 337-470nm
Note on M: classes are:
1 = metal-rich, 0.15 < [Fe/H]
0 = metal normal, -0.20 ≤ [Fe/H] ≤ 0.15
-1 = metal poor, [Fe/H] < -0.20
Note on Ref: codes are:
FEH = Cayrel de Strobel, 1985A&AS...59..145C 1985A&AS...59..145C
FFBG = Faber et al., 1985ApJS...57..711F 1985ApJS...57..711F
JHC = Jacoby et al., 1984ApJS...56..257J 1984ApJS...56..257J
L = Laird et al., 1988AJ.....95.1843L 1988AJ.....95.1843L
LB = Luck & Bond, 1985ApJ...292..559L 1985ApJ...292..559L
M83 = Keenan, 1983BICDS..24...19K 1983BICDS..24...19K
TTCB = Turnshek et al., 1985,
"An atlas of Digital Spectra of Cool stars",
Tucson: Western Research Company
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Byte-by-byte Description of file: spectra.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- SpNo [1,72] Spectrum number
5- 13 A9 --- Sp *Spectral class designation
14- 18 F5.2 mag (U-V)s ? Synthesized U-V colour
20- 24 F5.2 mag (B-V)s ? Synthesized B-V colour
26- 30 F5.2 mag (U-V)c ? Catalog U-V colour
32- 36 F5.2 mag (B-V)c ? Catalog B-V colour
38- 42 F5.2 mag (U-V)r ? Residuals U-V colour
44- 48 F5.2 mag (B-V)r ? Residuals B-V colour
50- 54 A5 --- Ref Reference
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Note on Sp:
this composite spectral class is used to designate the file
with spectrophotometric data (in "sp" subdirectory)
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Structure of files: sp/*.dat
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Bytes Format Units Label Explanations
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1- 5 F5.1 nm wavel central wavelength for each pixel
6- 13 F8.3 --- I normalized intensity to 100 at 545.0 nm
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Verification and Modifications:
* May 1992: files received and documented by Nancy G. Roman at
NASA/SSDOO/ADC.
* 25-Apr-1995, N.P.M. Kuin (NASA/SSDOO/ADC):
The data were received by the ADC as one large file. The individual
spectra were extracted and put in individual files. A wavelength scale
was appended explicitly to each file.
* 15-Sep-1999, Francois Ochsenbein, James Marcout (CDS):
files spectra.dat and stars.dat were added from tables of paper.
(End) Francois Ochsenbein, James Marcout [CDS] 15-Sep-1999