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)
|RAVE_OBS_ID||varchar||meta.id||Unique Identifier for RAVE objects, Observation Date, Fieldname, Fibernumber|
|RAJ2015||double||pos.eq.ra||deg||Gaia Right Ascension (J2015)|
|DEJ2015||double||pos.eq.dec||deg||Gaia Declination (J2015)|
|mas||Gaia DR1 position error RA at epoch 2015.0|
|mas||Gaia DR1 position error Dec at epoch 2015.0|
|flg||tinyint||meta.number||1=TGAS, 2=other UCAC-Gaia, 3=other NOMAD|
|n_Images||tinyint||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|
|mas/yr||proper motion RA*cosDEC (UCAC-Gaia)|
|mas/yr||proper motion (UCAC-Gaia)|
|mas/yr||formal error of UCAC-Gaia proper motion RA*cosDec|
|mas/yr||formal error of UCAC-Gaia proper motion Dec|
|mas||Gaia DR1 G magnitude|
|mag||mean UCAC model magnitude|
|mag||NOMAD photographic R mag|
|mag||2MASS J magnitude|
|mag||2MASS H magnitude|
|mag||2MASS K magnitude|
|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|