Crossmatch RAVE DR5 and UCAC5 (ravedr5.rave_ucac5)


Cross-matching of RAVEDR5 against UCAC5:

RAVE fiber has a diameter of 6.7″. The fiber positioning uncertainty is 0.7″ (see DR1 paper). With this in mind the cross-matching radius was set to 4.05″ (6.7 / 2 + 0.7). Cross-matching was done using the J2000 coordinates from both catalogs.

For every RAVE star all UCAC5 stars within the matching radius were collected. If there were multiple stars withing the radius the brightest one (in Gaia g-band magnitude) was chosen as the primary. The fluxes of the rest of the stars were added together. The ratio of their fluxes with respect to the primary’s flux was expressed as the contamination ratio (gmag_cont). For example, the value of 0.2 implies that the rest of the stars within the fiber radius contribute 20% of the flux in g-band.

While g-band magnitude is available for all cross-matches, some of the stars also have measurements from other bands. r-band and j-band contamination ratios are also available (rmag_cont, jmag_cont). They are computed in the same was as the g-band contamination ratio except using the different bands. Please note that regardless of the band in which the contamination ratio is computed the brightest star (primary) is always defined as the one with the lowest g-band magnitude.

Contamination ratios are set to NULL if there is only one UCAC5 star present in the cross-matching radius. If there are more stars, but magnitudes in r- or j-band are not available the contamination ratio is set to -1. This means there is some flux contribution from the surrounding stars but the value is unknown.

The distance to the primary matching star is given in the Dist_UCAC5 column. Crossmatch RAVEDR5 and UCAC5 (zone catalog)


Funding for Rave has been provided by:

  • the Leibniz Institute for Astrophysics Potsdam (AIP);
  • the Australian Astronomical Observatory;
  • the Australian National University;
  • the Australian Research Council;
  • the French National Research Agency;
  • the German Research Foundation (SPP 1177 and SFB 881);
  • the European Research Council (ERC-StG 240271 Galactica);
  • the Istituto Nazionale di Astrofisica at Padova;
  • the Johns Hopkins University;
  • the National Science Foundation of the USA (AST-0908326);
  • the W. M. Keck foundation;
  • the Macquarie University;
  • the Netherlands Research School for Astronomy;
  • the Natural Sciences and Engineering Research Council of Canada;
  • the Slovenian Research Agency;
  • the Swiss National Science Foundation;
  • the Science & Technology FacilitiesCouncil of the UK;
  • Opticon;
  • Strasbourg Observatory;
  • the Universities of Basel, Groningen, Heidelberg and Sydney.

This work has made use of data from the European Space Agency (ESA) mission Gaia (, processed by the GaiaData Processing and Analysis Consortium (DPAC, Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.


Name Type UCD Unit Description
rave_obs_id char

Unique Identifier for RAVE objects: Observation Date, Fieldname, Fibernumber

source_id long

Unique source identifier

raj2015 double pos.eq.ra deg

Gaia Right Ascension (J2015)

dej2015 double pos.eq.dec deg

Gaia Declination (J2015)

e_raj2015 double stat.error

Gaia DR1 position error RA at epoch 2015.0

e_dej2015 double stat.error

Gaia DR1 position error Dec at epoch 2015.0

flg short meta.number

1=TGAS, 2=other UCAC-Gaia, 3=other NOMAD

n_images short meta.number

Number of Images UCAC

ep_u double time.epoch year

mean UCAC epoch ( yr after 1997.0)

ra_u double pos.eq.ra deg

mean UCAC RA at epu epoch on Gaia reference frame

de_u double pos.eq.dec deg

deg mean UCAC Dec at epu epoch on Gaia reference frame

pmra_u double

proper motion RA*cosDEC (UCAC-Gaia)

pmde_u double

proper motion (UCAC-Gaia)

e_pmra_u double stat.error

formal error of UCAC-Gaia proper motion RA*cosDec

e_pmde_u double stat.error

formal error of UCAC-Gaia proper motion Dec

gmag float phot.mag

Gaia DR1 G magnitude

umag float phot.mag

mean UCAC model magnitude

rmag float phot.mag

NOMAD photographic R mag

jmag float
hmag float
kmag float
dist_ucac5 float pos.angDistance arcsec

Distance between RAVE and UCAC5 object coordinates in arcsec

g_cont double meta.code.qual

g-band flux ratio between contaminators and primary match

r_cont double meta.code.qual

r-band flux ratio between contaminators and primary match

j_cont double meta.code.qual

j-band flux ratio between contaminators and primary match