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COLL69XMM - Collinder 69 Cluster XMM-Newton X-Ray Point Source Catalog

HEASARC
Archive

Overview

This table contains some of the results from the first paper of a series devoted to the Lambda Orionis star-forming region, Orion's Head, from the X-ray perspective. The final aim of this research is to provide a comprehensive view of this complex region, which includes several distinct associations and dark clouds. The authors aim to uncover the population of the central, young star cluster Collinder 69, and in particular to find those diskless Class III pre-main sequence objects which have not been identified by previous surveys based on near- and mid-infrared searches, and to establish the X-ray luminosity function for the association.

The authors have combined two exposures taken with the XMM-Newton satellite with an exhaustive data set of optical, near- and mid-infrared photometry to assess the membership of the X-ray sources based on different color-color and color-magnitude diagrams, as well as other properties, such as effective temperatures, masses and bolometric luminosities derived from spectral energy distribution fitting and comparison with theoretical isochrones. The presence of circumstellar disks is discussed using mid-infrared photometry from the Spitzer Space Telescope.

This table contains the XMM-Newton X-ray point source catalog for all sources detected in the EPIC observations of the Collinder 69, East and West Fields (C69E and C69W), respectively, with maximum likelihood (ML) values > 15.0. A companion HEASARC Browse table COLL69OID contains optical and infrared data as well as membership information on counterparts to these X-ray sources.


Catalog Bibcode

2011A&A...526A..21B

References

XMM-Newton investigations of the {lambda} Orionis star-forming region (XILO).
I. The young cluster Collinder 69.
    Barrado D., Stelzer B., Morales-Calderon M., Bayo A., Huelamo N.,
    Stauffer J.R., Hodgkin S., Galindo F., Verdugo E.
   <Astron. Astrophys., 526, A21 (2011)>
   =2011A&A...526A..21B

Provenance

This table was created by the HEASARC in July 2011 based on the electronic versions of Tables 3 and 4 from the reference paper which were obtained from the CDS (their catalog J/A+A/526/A21 files table3.dat and table4.dat).

Parameters

Alt_Name
The source designation adopted by the authors in their paper, e.g., 'C69-X-eNNN' or 'C69-X-wNNN' for X-ray sources in the Collinder 69, East and West Fields (C69E and C69W), respectively, where NNN is a unique identification number for each field.

Instrument
The instrument used for the spectral analysis as discussed in Section 2.1 of the reference paper, where the following abbreviations are used:

    E: EPIC (European Photon Imaging Camera)
   PN: pn CCD
   M1: MOS-1 (Metal Oxide Semi-conductor-1) CCD
   M2: MOS-2 (Metal Oxide Semi-conductor-2) CCD
  

Name
The standard designation for the XMM-Newton X-ray source using the 'XMMU' prefix for 'XMM-Newton, Unregistered' and the J2000.0 coordinates. This was constructed by the HEASARC using the coordinates provided.

RA
The corrected Right Ascension of the X-ray source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.1 seconds of time in the original reference. The X-ray coordinates of the final source list were cross-correlated with the 2MASS catalog (Cutri et al. 2003), and a boresight correction was computed as the median of the astrometric offsets in RA and Declination.

Dec
The corrected Declination of the X-ray source in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.1 arcseconds in the original reference. The X-ray coordinates of the final source list were cross-correlated with the 2MASS catalog (Cutri et al. 2003), and a boresight correction was computed as the median of the astrometric offsets in RA and Declination.

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

Error_Radius
The statistical positional uncertainty of the X-ray source, in arcseconds.

Off_Axis
The off-axis angle of the X-ray source, in arcminutes.

Maximum_Likelihood
The maximum likelihood of the x-ray source detection.

Count_Rate
The broad-band count rate B of the X-ray source, in ct/s, where the soft (S), medium (M), hard (H) and broad (B) bands are defined as S = 0.5-1.0 keV, M = 1.0-2.0 keV, H = 2.0-7.3 keV, and B = 0.5-7.3 kev, i.e., S+M+H.

Count_Rate_Error
The RMS uncertainty in the X-ray source broad-band count rate, in ct/s.

Hardness_Ratio_1
The hardness ratio HR1 of the X-ray source. This is defined as HR1 = (M-S)/(M+S), where the soft (S), medium (M), hard (H) and broad (B) bands are defined as S = 0.5-1.0 keV, M = 1.0-2.0 keV, H = 2.0-7.3 keV, and B = 0.5-7.3 kev, i.e., S+M+H.

Hardness_Ratio_1_Error
The RMS uncertainty in the hardness ratio HR1 of the X-ray source..

Hardness_Ratio_2
The hardness ratio HR2 of the X-ray source. This is defined as HR2 = (H+M-S)/(H+M+S), where the soft (S), medium (M), hard (H) and broad (B) bands are defined as S = 0.5-1.0 keV, M = 1.0-2.0 keV, H = 2.0-7.3 keV, and B = 0.5-7.3 kev, i.e., S+M+H.

Hardness_Ratio_2_Error
The RMS uncertainty in the hardness ratio HR2 of the X-ray source.


Contact Person

Questions regarding the COLL69XMM database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 11-Jul-2011