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IC10XMMCXO - IC 10 XMM-Newton and Chandra X-Ray Point Source Catalog

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Overview

This table contains some of the results from an X-ray study of our nearest starburst galaxy IC 10, based on XMM-Newton and Chandra observations. It contains a list of 73 XMM-Newton and 28 Chandra detections of point-like X-ray sources in the field of this galaxy; a substantial fraction of them are likely to be stellar objects in the Milky Way due to the low Galactic latitude location of IC 10. The brightest source in the IC 10 field, X-1, has a mean 0.3-8.0 keV luminosity of ~1.2E38 erg s-1 and shows a large variation by a factor of up to ~6 on timescales of ~104 s during the XMM-Newton observation.

The XMM-Newton observations were taken on 2003 July 3 with a total exposure time of ~45 ks for the EPIC-MOS cameras and ~42 ks for the European Photon Imaging Camera (EPIC) PN camera. The authors use only the data from the PN camera (with a thin optical blocking filter) because of its high sensitivity to soft X-rays in the study of diffuse emission and include the data from the MOS cameras in the analysis of X-1. The Chandra observation, taken on 2003 March 12 with an exposure of 29 ks and already described by Bauer and Brandt (2004, ApJ, 601, 67), was reprocessed by the authors using the then-latest CIAO software (version 3.2.1) and calibration database (version 3.0.0).

The authors used the Two-Micron All Sky Survey (2MASS) All-Sky Catalog of Point Sources (Cutri et al. 2003 CDS Catalog II/246) to search for potential counterparts. They cross-correlated the spatial positions of the objects in this catalog with their X-ray source positions, using a matching radius of 4 arcsec for XMM-Newton PN sources and 2 arcsec for Chandra ACIS sources. The radius was chosen to be greater than the 1-sigma statistical position uncertainty of almost all the sources.In no case is there a match with multiple 2MASS objects. The 3-sigma limiting sensitivities of the 2MASS Catalog are 17.1, 16.4 and 15.3 mag in the three bands, J, H, and KS, respectively.


Catalog Bibcode

2005MNRAS.362.1065W

References

An XMM-Newton and Chandra study of the starburst galaxy IC 10.
    Wang Q.D., Whitaker K.E., Williams R.
   <Mon. Not. R. Astron. Soc., 362, 1065-1077 (2005)>
   =2005MNRAS.362.1065W

Provenance

This table was created by the HEASARC in October 2011 based on CDS Catalog J/MNRAS/362/1065 files table1.dat, table2.dat and table3.dat.

HEASARC Note

The authors did not attempt to produce a list of unique X-ray sources in this field, although they note that most of the brighter Chandra sources area also detected as XMM-Newton sources. The 3 XMM-Newton sources 'XP 35', 'XP 37' and 'XP 42' are listed in Table 3 of the reference paper as having the same 2MASS counterparts as the Chandra sources 'XA 14', 'XA 16' and 'XA 20', respectively, and thus represent 3 of these overlapping cases. Visual examination of Figure 5 in the reference paper shows that there are 7 or 8 other Chandra sources with likely XMM-Newton counterparts: 'XA 7', 'XA 9', 'XA 12', 'XA 15', 'XA 18', 'XA 26', 'XA 28', and possibly 'XA 23', meaning that there are around 90 unique X-ray sources in this table of 73 XMM-Newton and 28 Chandra sources.

Parameters

Source_Identifier
A unique X-ray source identifier of the form 'XA NN' for the Chandra X-ray sources and 'XP NN' for the XMM-Newton X-ray sources, Within each category, the numbering of the sources is in order of increasing J2000.0 Right Ascension.

Alt_Name
An alternative source designation recommended by the Dictionary of Nomenclature of Celestial Objects using the '[WWW2005]' prefix (for Wang, Whitaker, Williams 2005) and the source identifier, e.g., '[WWW2005] XP 1'.

Name
The primary J2000.0 position-based X-ray source designation, following the conventions recommended by the Dictionary of Nomenclature of Celestial Objects for unregistered XMM-Newton and Chandra X-ray sources, viz., 'XMMU JHHMMSS.s+DDMMSS' and 'CXOU JHHMMSS.s+DDMMSS', respectively. The HEASARC has reduced the 'JHHMMSS.ss+DDMMSS.s' precision used for these sources in the original table to conform to these standards.

RA
The Right Ascension of the X-ray source in the selected equinox. This was constructed by the HEASARC from the J2000.0 position-based name of the X-ray source which was given to a precision of 0.01 seconds of time in the original reference table.

Dec
The Declination of the X-ray source in the selected equinox. This was constructed by the HEASARC from the J2000.0 position-based name of the X-ray source which was given to a precision of 0.1 aercseconds in the original reference table.

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

Error_Radius
The 1-sigma positional uncertainty of the X-ray source, in arcseconds, calculated from the maximum likelihood centroiding.

Count_Rate
The on-axis source broad-band count rate, in ct s-1, being the sum of the exposure-corrected count rates in the 4 energy bands (which are defined differently from the XMM-Newton PN and Chandra ACIS instruments, notice).

Count_Rate_Error
The uncertainty in the on-axis broad-band count rate of the X-ray source, in ct s-1.

Hardness_Ratio
The hardness ratio, HR = (H-S2)/(H+S2), listed only for values with uncertainties of less than 0.2, where the definitions of the count rates in the various energy bands for the XMM-Newton PN and Chandra ACIS instruments are as follows:

    Band      XMM-Newton     Chandra
              Energy Range   Energy Range
     S1      0.5 - 1.0 keV  0.3 - 0.7 keV
     S2      1.0 - 2.0      0.7 - 1.5
     H1      2.0 - 4.5      1.5 - 3.0
     H2      4.5 - 7.5      3.0 - 7.0
  
In addition, S = S1 + S2, H = H1 + H2, and B + S + H.

Hardness_Ratio_Error
The uncertainty in the hardness ratio, HR.

Hardness_Ratio_1
The hardness ratio, HR1 = (S2-S1)/S, listed only for values with uncertainties of less than 0.2, where the definitions of the count rates in the various energy bands for the XMM-Newton PN and Chandra ACIS instruments are as follows:

    Band      XMM-Newton     Chandra
              Energy Range   Energy Range
     S1      0.5 - 1.0 keV  0.3 - 0.7 keV
     S2      1.0 - 2.0      0.7 - 1.5
     H1      2.0 - 4.5      1.5 - 3.0
     H2      4.5 - 7.5      3.0 - 7.0
  
In addition, S = S1 + S2, H = H1 + H2, and B + S + H.

Hardness_Ratio_1_Error
The uncertainty in the hardness ratio, HR1.

Notes
This notes fields contains flags indicating the band(s) in which a source was detected with the most accurate position(s) which were adopted: 'B', 'S' or 'H' for the corresponding energy bands as defined above.

TwoMASS_Name
The matching 2MASS source name in the form recommended by the Dictionary of Nomenclature of Celestial Objects, viz., '2MASS JHHMMSSss+DDMMSSs'. In the published table 3 of the reference paper, these names were given in the form '2MASS JHHMMSS.ss+DDMMSS.s'

Offset
The positional offset between the X-ray and the 2MASS sources, in arcseconds.

Jmag
The J-band magnitude of the matching 2MASS source.

Hmag
The H-band magnitude of the matching 2MASS source.

Ks_Mag
The Ks-band magnitude of the matching 2MASS source.


Contact Person

Questions regarding the IC10XMMCXO database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 28-Aug-2012