J/ApJ/518/859 Revision of MK luminosity classes (Keenan+, 1999)
Revision and calibration of MK luminosity classes for cool giants by
HIPPARCOS parallaxes
Keenan P.C., Barnbaum C.
<Astrophys. J. 518, 859 (1999)>
=1999ApJ...518..859K 1999ApJ...518..859K
ADC_Keywords: MK spectral classification ; Parallaxes, trigonometric ;
Spectral types ; Stars, late-type ; Stars, standard
Keywords: astrometry - standards - stars: fundamental parameters
Abstract:
The Hipparcos parallaxes of cool giants are utilized in two ways in
this paper. First, a plot of reduced parallaxes of stars brighter than
6.5, as a function of spectral type, for the first time separates
members of the clump from stars in the main giant ridge. A slight
modification of the MK luminosity standards has been made so that
luminosity class IIIb defines members of the clump, and nearly all of
the class III stars fall within the main giant ridge. Second, a new
calibration of MK luminosity classes III and IIIb in terms of visual
absolute magnitudes has been made.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 76 142 Revised MK types for cool stars
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
III/150 : Perkins Revised MK Types for the Cooler Stars (Keenan+ 1989)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Star name
20- 24 I5 --- HD Henry Draper catalog number
26- 29 F4.2 mag Vmag V band magnitude
31 A1 --- f_Vmag [v] Indicates a variable star
33 I1 h RAh Right Ascension (J2000)
35- 38 F4.1 min RAm Right Ascension (J2000)
40 A1 --- DE- Declination (J2000)
41- 42 I2 deg DEd Declination (J2000)
45- 46 I2 arcmin DEm Declination (J2000)
50- 63 A14 --- Class Spectral and Luminosity type
65 A1 --- f_Class Indicates star is not a reliable standard
for stars of normal solar composition
69- 72 I4 10-5arcsec Para Reduced parallax (x10-5)
74- 76 I3 10-5arcsec e_Para Uncertainty in Para
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History:
From ApJ electronic edition
March 2000: Parallax of 81 Gem changed from I800 to 1800.
(End) Greg Schwarz [AAS] 08-Mar-2000