J/MNRAS/411/435 Stellar parameters and extinction (Bailer-Jones, 2011)
Bayesian inference of stellar parameters and interstellar extinction using
parallaxes and multiband photometry.
Bailer-Jones C.A.L.
<Mon. Not. R. Astron. Soc. 411, 435 (2011)>
=2011MNRAS.411..435B 2011MNRAS.411..435B
ADC_Keywords: Stars, normal ; Effective temperatures ; Extinction ;
Photometry, UBV ; Photometry, infrared ; Parallaxes, trigonometric
Keywords: methods: data analysis - methods: statistical - surveys -
stars: fundamental parameters -
Hertzsprung-Russell and colour-magnitude diagrams - dust, extinction
Abstract:
Astrometric surveys provide the opportunity to measure the absolute
magnitudes of large numbers of stars, but only if the individual
line-of-sight extinctions are known. Unfortunately, extinction is
highly degenerate with stellar effective temperature when estimated
from broad band optical/infrared photometry. To address this problem,
I introduce a Bayesian method for estimating the intrinsic parameters
of a star and its line-of-sight extinction.
Description:
Effective temperatures (Teff) and interstellar extinctions (A0) for
46900 Hipparcos stars based on their optical BV and infrared (2MASS)
JHK photometry are presented. The stellar parameters were inferred
using a Bayesian method. In addition to the Mean parameter estimate
(Mean of the posterior probability distribution), the catalogue also
provides the Lower and Upper values of the 90% confidence interval
(CI) of the probability distribution. Estimates are provided for two
methods: the p-model, which uses only the BVJHK colours (and
uncertainties thereon); the pq-model, which additionally uses the
apparent V-band magnitude and the Hipparcos parallax (plus
uncertainties) as well as parameter prior distribution formed from a
model Hertzsprung-Russel Diagram. Note that A0 is an extinction
parameter and is not quite identical to the extinction in the V band.
An explanation of why this is so, plus a convenient conversion
equation, are given in the article.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
h2mqcat.dat 142 46900 Stellar parameter estimates and uncertainties
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: h2mqcat.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP Hipparcos (Cat. I/239) identifier (1)
8- 13 F6.4 [K] logT.p ? Mean estimate of log(Teff) from the p-model
15- 20 F6.4 [K] b_logT.p ? Lower bound of 90% CI to log(Teff), p-model
22- 27 F6.4 [K] B_logT.p ? Upper bound of 90% CI to log(Teff), p-model
29- 32 F4.2 mag A0.p ? Mean estimate of extinction A0 from the p-model
34- 37 F4.2 mag b_A0.p ? Lower bound of 90% CI to A0.p, p-model
39- 42 F4.2 mag B_A0.p ? Upper bound of 90% CI to A0.p, p-model
44- 49 F6.4 [K] logT.pq ? Mean estimate of log(Teff) from the pq-model
51- 56 F6.4 [K] b_logT.pq ? Lower bound of 90% CI to log(Teff), pq-model
58- 63 F6.4 [K] B_logT.pq ? Upper bound of 90% CI to log(Teff), pq-model
65- 68 F4.2 mag A0.pq ? Mean estimate of A0 from the pq-model
70- 73 F4.2 mag b_A0.pq ? Lower bound of 90% CI to A0.pq, pq-model
75- 78 F4.2 mag B_A0.pq ? Upper bound of 90% CI to A0.pq, pq-model
80- 84 F5.2 mag Bmag B-band magnitude
86- 90 F5.2 mag Vmag V-band magnitude
92- 97 F6.3 mag Jmag J-band magnitude
99-103 F5.3 mag e_Jmag 1σ uncertainty in Jmag
105-110 F6.3 mag Hmag H-band magnitude
112-116 F5.3 mag e_Hmag 1σ uncertainty in Hmag
118-123 F6.3 mag Kmag K-band magnitude
125-129 F5.3 mag e_Kmag 1σ uncertainty in Kmag
131-136 F6.2 mas plx Parallax
138-142 F5.2 mas e_plx 1σ uncertainty in plx
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Note (1): A fraction of the stars have no parameters estimates from one of
the methods.
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Acknowledgements:
Coryn Bailer-Jones, calj(at)mpia.de
(End) Coryn Bailer-Jones [MPIA, Heidelberg], Patricia Vannier [CDS] 24-Sep-2010