Access to Astronomical Catalogues

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
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:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
h2mqcat.dat      142    46900   Stellar parameter estimates and uncertainties


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

   Bytes Format Units  Label   Explanations

   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

Note (1): A fraction of the stars have no parameters estimates from one of
     the methods.


Acknowledgements:
    Coryn Bailer-Jones, calj(at)mpia.de
(End)  Coryn Bailer-Jones [MPIA, Heidelberg], Patricia Vannier [CDS] 24-Sep-2010