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M31XMMXRAY - XMM-Newton M31 Survey Source Catalog

HEASARC
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Overview

This table contains a source catalog based on XMM-Newton observations of the bright Local Group spiral galaxy M 31. In an analysis of XMM archival observations of M 31, the authors studied the population of X-ray sources (X-ray binaries, supernova remnants) down to a 0.2-4.5 keV luminosity of 4.4 x 10^34 erg/s. EPIC hardness ratios and optical and radio information were used to distinguish between different source classes. The survey detected 856 sources in an area of 1.24 square degrees. The authors correlated their sources with earlier M 31 X-ray catalogues and used information from optical, infra-red and radio wavelengths. As sources within M 31, they detected 21 supernova remnants (SNR) and 23 SNR candidates, 18 supersoft source (SSS) candidates, 7 X-ray binaries (XRBs) and 9 XRB candidates, as well as 27 globular cluster sources (GlC) and 10 GlC candidates, which most likely are low mass XRBs within the GlC. Comparison to earlier X-ray surveys revealed transients not detected with XMM-Newton, which add to the number of M 31 XRBs. There are 567 sources classified as hard, which might either be XRBs or Crab-like SNRs in M 31 or background AGN. The number of 44 SNRs and candidates more than doubles the X-ray-detected SNRs. 22 sources are new SNR candidates in M 31 based on X-ray selection criteria. Another SNR candidate might be the first plerion detected outside the Galaxy and the Magellanic Clouds. On the other hand, six sources are foreground stars and 90 are foreground star candidates, one is a BL Lac-type active galactic nucleus (AGN) and 36 are AGN candidates, one source coincides with the Local Group galaxy M 32, one with a background galaxy cluster (GCl) and another is a GCl candidate, all sources which are not connected with M31.

In a second paper, the authors presented an extension to the original 2005 XMM-Newton X-ray source catalog of M 31 which contained 39 newly found sources. These sources have been added to the original 856 sources to make a combined catalog of 895 X-ray sources which is contained herein.


Catalog Bibcodes

2005A&A...434..483P
2008A&A...480..599S

References

An XMM-Newton survey of M 31. [Paper I].
    Pietsch W., Freyberg M., Haberl F.
   <Astron. Astrophys. 434, 483 (2005)>
   =2005A&A...434..483P

Time variability of X-ray sources in the M 31 centre field. [Paper II].
    Stiele H., Pietsch W., Haberl F., Freyberg M.
   <Astron. Astrophys. 480, 599 (2008)>
   =2008A&A...480..599S

Provenance

This table was originally created by the HEASARC in May 2005 based on the CDS table J/A+A/434/483/ file table2.dat (sources numbered 1 to 856). It was updated by the HEASARC in June 2008 by adding the 39 sources from the CDS table J/A+A/480/599/ file table3.dat (sources numbered 857 to 895).

Parameters

Source_Number
A unique identification number for each X-ray source in the catalog. Sources numbered from 1 to 856 are from Pietsch et al. (2005, Paper I), while those sources numbered from 857 to 895 are from Stiele et al. (2008, Paper II).

Name
The recommended designation for sources in this catalog, using the prefix '[PFH2005] ' (for Pietsch, Freyberg, Haberl 2005) and a running source number for the X-ray source in order of increasing J2000 Right Ascension.

Field_Code
The code for the detection field from which the source was entered into the catalog, where 'c' stands for Center, 'n' for North, 's' for South, and 'h' for Halo. The information about the fields, including their pointing directions, filters used, and exposures, is given in Table 1 of the published paper and is also available at ftp://cdsarc.u-strasbg.fr/pub/cats/J/A+A/434/483/table1.dat .

RA
The Right Ascension of the X-ray source in the selected equinox. This was given in J2000 coordinates and to a precision of 0.01 seconds of time in the originating table.

Dec
The Declination of the X-ray source in the selected equinox. This was given in J2000 coordinates and to a precision of 0.1 arcseconds of time in the originating table.

LII
The Galactic Longitude of the X-ray source.

BII
The Galactic Latitude of the X-ray source.

Alt_Name
An alternative name for the X-ray source using the 'XMMM31' prefix (for XMM-Newton M 31 field) and the truncated J2000 positional coordinates, as registered with the CDS Dictionary of Nomenclature of Celestial Objects, e.g., 'XMMM31 J004250.4+411556'.

Error_Radius
The 1-sigma statistical error in the position, in arcseconds. This does not include a residual systematic error which amounts to ~ 0.5 arcseconds and should be added in quadrature to the statistical error to get the total positional uncertainty.

Det_ML
The detection likelihood for the X-ray source based on the combined EPIC PN, MOS1, and MOS2 data.

Count_Rate
The integrated EPIC PN, MOS1, and MOS2 count rate, in counts per second, in the XID band corresponding to the 0.2-4.5 keV energy range.

Count_Rate_Error
The error in the combined EPIC count rate, in counts per second.

Flux
The X-ray flux in the 0.2-4.5 keV energy range based on the combined EPIC PN, MOS1, and MOS2 data, in erg/s/cm^2.

Flux_Error
The error in the combined EPIC PN, MOS1, and MOS2 flux, in erg/s/cm^2.

HR1
The Hardness Ratio HR1 of the combined EPIC X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

HR1_Error
The error in the combined EPIC Hardness Ratio HR1. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

HR2
The Hardness Ratio HR2 of the combined EPIC X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

HR2_Error
The error in the combined EPIC Hardness Ratio HR2. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

HR3
The Hardness Ratio HR3 of the combined EPIC X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

HR3_Error
The error in the combined EPIC Hardness Ratio HR3. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

HR4
The Hardness Ratio HR4 of the combined EPIC X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

HR4_Error
The error in the combined EPIC Hardness Ratio HR4. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

Det_Instruments
Codes indicating which EPIC instruments contributed to the X-ray source detection, where the first character is for the EPIC PN, the second is for the EPIC MOS1, and the third is for the EPIC MOS2: a value of 'T' indicates that the X-ray source is in the field of view (FOV) of the instrument, while a value of 'F' indicates otherwise. There are 52 sources at the periphery of the FOV for which only some of the EPIC instruments contribute.

PN_Exposure
The exposure of the EPIC PN instrument, in seconds. This parameter was given with a precision of 0.1 kiloseconds in the original, as-published table.

PN_Det_ML
The detection likelihood for the X-ray source based on the EPIC PN data.

PN_Count_Rate
The EPIC PN count rate, in counts per second, in the XID band corresponding to the 0.2-4.5 keV energy range.

PN_Count_Rate_Error
The error in the EPIC PN count rate, in counts per second.

PN_Flux
The X-ray flux in the 0.2-4.5 keV energy range based on the EPIC PN data, in erg/s/cm^2.

PN_Flux_Error
The error in the EPIC PN flux, in erg/s/cm^2.

PN_HR1
The Hardness Ratio HR1 of the EPIC PN X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

PN_HR1_Error
The error in the EPIC PN Hardness Ratio HR1. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

PN_HR2
The Hardness Ratio HR2 of the EPIC PN X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

PN_HR2_Error
The error in the EPIC PN Hardness Ratio HR2. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

PN_HR3
The Hardness Ratio HR3 of the EPIC PN X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

PN_HR3_Error
The error in the EPIC PN Hardness Ratio HR3. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

PN_HR4
The Hardness Ratio HR4 of the EPIC PN X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

PN_HR4_Error
The error in the EPIC PN Hardness Ratio HR4. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M1_Exposure
The exposure of the EPIC MOS1 instrument, in seconds. This parameter was given with a precision of 0.1 kiloseconds in the original, as-published table.

M1_Det_ML
The detection likelihood for the X-ray source based on the EPIC MOS1 data.

M1_Count_Rate
The EPIC MOS1 count rate, in counts per second, in the XID band corresponding to the 0.2-4.5 keV energy range.

M1_Count_Rate_Error
The error in the EPIC MOS1 count rate, in counts per second.

M1_Flux
The X-ray flux in the 0.2-4.5 keV energy range based on the EPIC MOS1 data, in erg/s/cm^2.

M1_Flux_Error
The error in the EPIC MOS1 flux, in erg/s/cm^2.

M1_HR1
The Hardness Ratio HR1 of the EPIC MOS1 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

M1_HR1_Error
The error in the EPIC MOS1 Hardness Ratio HR1. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M1_HR2
The Hardness Ratio HR2 of the EPIC MOS1 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

M1_HR2_Error
The error in the EPIC MOS1 Hardness Ratio HR2. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M1_HR3
The Hardness Ratio HR3 of the EPIC MOS1 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

M1_HR3_Error
The error in the EPIC MOS1 Hardness Ratio HR3. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M1_HR4
The Hardness Ratio HR4 of the EPIC MOS1 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  
Hardness Ratios are calculated only for sources for which at least one of the two bands count rates has a significance greater than 2-sigma.

M1_HR4_Error
The error in the EPIC MOS1 Hardness Ratio HR4. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M2_Exposure
The exposure of the EPIC MOS2 instrument, in seconds. This parameter was given with a precision of 0.1 kiloseconds in the original, as-published table.

M2_Det_ML
The detection likelihood for the X-ray source based on the EPIC MOS2 data.

M2_Count_Rate
The EPIC MOS2 count rate, in counts per second, in the XID band corresponding to the 0.2-4.5 keV energy range.

M2_Count_Rate_Error
The error in the EPIC MOS2 count rate, in counts per second.

M2_Flux
The X-ray flux in the 0.2-4.5 keV energy range based on the EPIC MOS2 data, in erg/s/cm^2.

M2_Flux_Error
The error in the EPIC MOS2 flux, in erg/s/cm^2.

M2_HR1
The Hardness Ratio HR1 of the EPIC MOS2 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  

M2_HR1_Error
The error in the EPIC MOS2 Hardness Ratio HR1. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M2_HR2
The Hardness Ratio HR2 of the EPIC MOS2 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  

M2_HR2_Error
The error in the EPIC MOS2 Hardness Ratio HR2. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M2_HR3
The Hardness Ratio HR3 of the EPIC MOS2 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  

M2_HR3_Error
The error in the EPIC MOS2 Hardness Ratio HR3. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

M2_HR4
The Hardness Ratio HR4 of the EPIC MOS2 X-ray source. The hardness ratios are defined by the relation HRi=(R(i+1)-R(i))/(R(i+1)+R(i)) where Ri are the count rates in the energy bands 1 to 5, and the bands correspond to the following energies:

             band 1 = 0.2-0.5keV,
             band 2 = 0.5-1.0keV,
             band 3 = 1.0-2.0keV,
             band 4 = 2.0-4.5keV,
             band 5 = 4.5-12keV
  

M2_HR4_Error
The error in the EPIC MOS2 Hardness Ratio HR4. Errors are the properly combined statistical errors in each band and can extend beyond the range of allowed values of hardness ratios of -1.0 to +1.0.

Alt_Xray_Id1
Cross-correlation information on previously identified X-Ray sources in the M 31 field, with the following codes for references:

             Code             = Reference

      TF91                    = Trinchieri et al., 1991ApJ...382...82T
      CRP90                   = Collura et al., 1990ApJ...356..119C
      PFJ93                   = Primini et al., 1993ApJ...410..615P
      SHP97                   = Supper et al., 1997A&A...317..328S
      CXOGMP Jhhmmss.s+ddmmss = Garcia et al., 2000ApJ...537L..23G
      SHL2001                 = Supper et al., 2001A&A...373...63S
      OBT2001                 = Osborne et al., 2001A&A...378..800O
      am-n                    = Kong et al., 2002ApJ...577..738K
                                Di Stefano et al., 2004ApJ...610..247D
                                Williams et al., 2004ApJ...609..735W
      DKG2002                 = Di Stefano et al., 2002ApJ...570..618D
      Jhhmmss.s+ddmmss        = Kaaret, 2002ApJ...578..114K
      TKP2004                 = Trudolyubov et al., astro-ph/0401227
  

Alt_Xray_Id2
Cross-correlation information on previously identified X-Ray sources in the M 31 field, using the same codes for references as for the parameter alt_xray_id1 (q.v.).

Alt_Xray_Id3
Cross-correlation information on previously identified X-Ray sources in the M 31 field, using the same codes for references as for the parameter alt_xray_id1 (q.v.).

Alt_Xray_Id_Others
Cross-correlation information on previously identified X-Ray sources in the M 31 field, using the same codes for references as for the parameter alt_xray_id1 (q.v.). Multiple name codes are separated by commas.

USNO_Cat_Name
The name of the (optically) brightest USNO-B1.0 (CDS Catalog <I/284>) source within the search area centered on the X-ray source having a radius of 3 times the combined statistical and systematic positional errors for the source.

Number_USNO_Corr
The number of USNO-B1.0 objects found within the search area of the X-ray source.

Offset_USNO_XMM
The angular offset from the USNO-B1.0 Source to the X-ray source, in arcseconds.

B2_Mag
The B2 magnitude of the brightest USNO-B1.0 source.

R2_Mag
The R2 magnitude of the brightest USNO-B1.0 source.

Imag
The I magnitude of the brightest USNO-B1.0 source.

Log_Fx_Fopt
The logarithm of the ratio of the Xray and optical fluxes, fX/fopt. To improve on the reliability of identifications, the authors used the B2 and R2 magnitudes to calculate this ratio, using the relation log fx/fopt = log fx + (b2_mag + r2_mag)/(2x2.5) + 5.37, following Maccacaro et al (1988, ApJ, 326, 680).

Source_Type
The catalogued X-Ray sources are identified or classified based on their properties in X-rays (such as hardness ratios, variability, extent) and of the correlated objects in other wavelength regimes. The criteria used are summarized in Table 4 of the published paper containing the catalog and are similar to those used in Paper I (Pietsch et al. 2004, A&A, 426, 11) for M 33. However, M 31 is more massive than M 33 with more interstellar matter in the disk, which, in addition, is more inclined. Therefore, sources in or behind M 31 may suffer higher absorption than similar sources in the M 33 field. To take this into account, the authors compared their HRs to model HRs determined assuming Galactic foreground absorption and additional absorption within M 31 of 9 x 10^21 cm^-2, a factor of 2 higher than in Paper I. A source is counted as identified if there least two criteria secure the identification, otherwise it is only considered as `classified', as indicated by the angle brackets. Many foreground stars, SSSs and SNRs were classified or identified. However, besides a few clearly identified XRBs and AGN, and SNR candidates from positions at other wavelengths, the authors had no clear hardness ratio criteria to select XRBs, Crab-like SNR or AGN. These latter are all `hard' sources, and the authors therefore introduced a class called <hard> for sources with a value of HR2 - HR2_error > -0.2. 38 sources remain unidentified or without classification.

The following classifications were used:

      Classification     Meaning

      fg Star   = foreground star
      <fg Star> = foreground star candidate
      AGN       = active galactic nucleus
      <AGN>     = AGN candidate
      GAL       = galaxy
      GCl       = galaxy cluster
      <GCl>     = galaxy cluster candidate
      SSS       = supersoft source in M 31
      <SSS>     = supersoft source candidate in M 31
      SNR       = supernova remnant in M 31
      <SNR>     = supernova remnant candidate in M 31
      GlC       = source in globular cluster
      <GlC>     = source in globular cluster candidate
      XRB       = X-ray binary in M 31
      <XRB>     = X-ray binary candidate in M 31
      <hard>    = HR2-e_HR2>-0.2 or only HR3 and HR4 defined, and no other
                  classification
  

Other_Remarks
This parameter contains some additional remarks about (some of) the X-ray sources, such as more details about the optical identification, and reference. The full references corresponding to the reference codes are given in ftp://cdsarc.u-strasbg.fr/pub/cats/J/A+A/434/483/refs.dat

Class
A (crude) HEASARC Browse classification for the object, based only on the information in the source_type field (i.e., any more detailed source information in the other_remarks field was not considered for this).


Contact Person

Questions regarding the M31XMMXRAY database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 30-Jun-2008