Table information for 'gdr2dist.main'

General

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Resource Description:

This catalogue provides distances estimates (and uncertainties therein) for 1.33 billion stars over the whole sky brighter than about G=20.7. These have been estimated using the parallaxes (and their uncertainties) from Gaia DR2. A Bayesian procedure was used involving a prior with a single parameter L(l,b), which varies smoothly with Galactic longitude and latitude according to a Galaxy model. The posterior is summarized with a point estimate (usually the mode) and a confidence interval (usually the 68% highest density interval). The estimation procedure is described in detail in the accompanying paper, which also analyses the catalogue content.

For a list of all services and tables belonging to this table's resource, see Information on resource 'Estimated distances to 1.33 billion stars in Gaia DR2'

Citing this table

This table has an associated publication. If you use data from it, it may be appropriate to reference 2018AJ....156...58B (ADS BibTeX entry for the publication) either in addition to or instead of the service reference.

To cite the table as such, we suggest the following BibTeX entry:

@MISC{vo:gdr2dist_main,
  year=2018,
  title={Estimated distances to 1.33 billion stars in Gaia DR2},
  author={Bailer-Jones, C.A.L. and Rybizki, J. and Fouesneau, M. and Mantelet, G. and Andrae, R.},
  url={http://dc.zah.uni-heidelberg.de/tableinfo/gdr2dist.main},
  howpublished={{VO} resource provided by the {GAVO} Data Center}
}

Columns

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NameTable Head DescriptionUnitUCD
source_id Source Id Unique source identifier. Note that this *cannot* be matched against the DR1 source_id. [Note id] N/A meta.id;meta.main
r_est Dist Estimated distance pc pos.distance
r_lo Min. Dist. Lower bound on the 1 σ confidence interval pc pos.distance;stat.min
r_hi Max. Dist. Upper bound on the 1 σ confidence interval pc pos.distance;stat.max
r_len Prior scale Length scale used in the prior for the distance estimation. pc stat.fit.param;pos.distance
result_flag Res. Code Type of result. [Note rc] N/A meta.code.qual
modality_flag #modes Result regime flag: number of modes in the posterior (1 or 2). N/A meta.code

Columns that are parts of indices are marked like this.

Other

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Notes

Note rc

result_flag has three possible values:

0:failed estimate (r_est, r_lo, r_hi are all NaN)
1:_est is the mode (highest if the posterior is bimodal); r_lo/r_hi define the lower/upper limits of the highest density interval (HDI) containing 68% of the posterior probability
2:r_est is the median; r_lo/r_hi define the lower/upper limits of the equal-tailed interval (ETI), containing 68% of the posterior probability."

99.9% of the rows have result_code=1.