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RASS2MASS - ROSAT All-Sky Survey BSC/2MASS PSC Cross-Associations XID II Catalog

HEASARC
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Overview

The 18,806 ROSAT All Sky Survey Bright Source Catalog (RASS/BSC) X-ray sources are quantitatively cross-associated with near-infrared (NIR) sources from the Two Micron All Sky Survey Point Source Catalog (2MASS/PSC). An association catalog is presented, listing the most likely counterpart for each RASS/BSC source, the probability P_id (called id_prob in the HEASARC version of this catalog) that the NIR source and X-ray source are uniquely associated, and the probability P_no-id (called no_id_prob in the HEASARC version of this catalog) that none of the 2MASS/PSC sources are associated with the X-ray source. The catalog includes 3853 high quality (P_id>0.98) X-ray-NIR matches, 2280 medium quality (0.98 >= P_id > 0.9) matches, and 4153 low quality (0.9 >= P_id > 0.5) matches. Of the high quality matches, 1418 are associations that are not listed in the SIMBAD database, and for which no high quality match with a USNO-A2 optical source was presented for the RASS/BSC source in previous work (Rutledge et al. 2000, ApJS, 131, 335). The present work offers a significant number of new associations with RASS/BSC objects that will require optical/NIR spectroscopy for classification. For example, of the 6133 P_id > 0.9 2MASS/PSC counterparts presented in the association catalog, 2411 have no classification listed in the SIMBAD database. These 2MASS/PSC sources will likely include scientifically useful examples of known source classes of X-ray emitters (white dwarfs, coronally active stars, active galactic nuclei), but they may also contain previously unknown source classes. It is determined that all coronally active stars in the RASS/BSC should have a counterpart in the 2MASS/PSC, and that the unique association of these RASS/BSC sources with their NIR counterparts thus is confusion limited.

Catalog Bibcode

2009ApJS..184..138H

References

XID II: Statistical Cross-Association of ROSAT Bright Source Catalog X-ray
Sources with 2MASS Point Source Catalog Near-Infrared Sources.
      Haakonsen, C.B., Rutledge, R. E.
     <Astrophys. J. Suppl. Ser. 184, 138 (2209)>
     =2009ApJS..184..138H

Provenance

This table was created by the HEASARC in October 2009 based on an electronic version of Table 3 (the 'Association Catalog') from the paper which were obtained from the Astrophysical Journal web site.

Parameters

Name
The RASS name of the X-ray source using the recommended '1RXS' prefix and the J2000 equatorial coordinates of the source.

RA
The Right Ascension of the X-ray source in the selected equinox. This was constructed (by the HEASARC) from its position-based name.

Dec
The Declination of the X-ray source in the selected equinox. This was constructed (by the HEASARC) from its position-based name

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

SIMBAD_Type_Rass
The SIMBAD source type of the RASS/BSC source.

Count_Rate
The RASS/BSC X-ray source count rate, in ct/s.

Count_Rate_Error
The RASS/BSC X-ray source count rate uncertainty, in ct/s.

No_Id_Prob
The probability that none of the off-band (2MASS/PSC) sources within 75 arcseconds of the X-ray source position are associated with the X-ray source.

TwoMASS_Name
The 2MASS/PSC near-infrared source designation of the most likely (highest value of id_prob) counterpart to the X-ray source.

SIMBAD_Type_2MASS
The SIMBAD source type of the 2MASS/PSC source.

Jmag
The 2MASS/PSC source J-band magnitude of the most likely (highest value of id_prob) counterpart to the X-ray source

ID_Prob
The probability that the most likely off-band (2MASS/PSC) source is uniquely associated with the X-ray source.

Class
The HEASARC Browse object classification, based on the Simbad type of the 2MASS source, else on the Simbad type of the RASS source


Contact Person

Questions regarding the RASS2MASS database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 9-Oct-2009