XMM-Newton M 33 Survey Catalog XMM/M33 ivo://nasa.heasarc/m33xmmxray NASA/GSFC HEASARC Pietsch et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table contains a source catalog based om XMM-Newton observations of the nearby galaxy M 33. In an XMM-Newton raster observation of this bright Local Group spiral galaxy, the authors studied the population of X-ray sources (X-ray binaries, supernova remnants) down to a 0.2-4.5 keV luminosity limit of 10&lt;sup&gt;35&lt;/sup&gt; erg/s, more than a factor of 10 deeper than earlier ROSAT observations. European Photon Imaging Camera (EPIC) hardness ratios and optical and radio information are used to distinguish between different source classes. The survey detects 408 sources in an area of 0.80 square degree. The authors correlated these newly detected X-ray sources with earlier M 33 X-ray catalogs and information from optical, infra-red and radio wavelengths. As M 33 sources, theydetect 21 supernova remnants (SNR) and 23 SNR candidates, 5 super-soft sources and 2 X-ray binaries (XRBs). There are 267 sources classified as hard, which may either be XRBs or Crab-like SNRs in M 33 or background AGN. The 44 confirmed and candidate SNRs more than double the number of X-ray detected SNRs in M 33. 16 of these are proposed as SNR candidates from the X-ray data for the first time. On the other hand, there are several sources not connected to M 33: five foreground stars, 30 foreground star candidates, 12 active galactic nucleus candidates, one background galaxy and one background galaxy candidate. Extrapolating from deep field observations, 175 to 210 background sources are expected in this field. This indicates that about half of the sources which were detected are actually within M 33. This table was created by the HEASARC in October 2004 based on CDS table J/A+A/426/11/table3.dat This is a service provided by NASA HEASARC . 2004A&amp;A...426...11P https://heasarc.gsfc.nasa.gov/W3Browse/all/m33xmmxray.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=m33xmmxray& GET text/xml 180 99999 true 23.213625 30.137 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=m33xmmxray GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_m33xmmxray&Action=More+Options&Action=Parameter+Search&ConeAdd=1 XMM-NEWTON 0.0166666666666667 X-ray public m33xmmxray XMM-Newton M 33 Survey Catalog name Source Designation meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable error_radius Positional Error (arcsec) arcsec stat.error;pos float nullable count_rate Combined EPIC Count Rate ct/s phot.count;em.X-ray double nullable count_rate_error Error in EPIC Count Rate ct/s stat.error;phot.count;em.X-ray double nullable flux Combined EPIC Flux (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray double nullable flux_error Error in Combined EPIC Flux erg/s/cm^2 stat.error;phot.flux;em.X-ray double nullable class Browse Object Classification src.class short nullable hr4 Combined EPIC Hardness Ratio 4 float nullable pn_det_ml EPIC PN Source Detection Likelihood double nullable pn_hr1_error Error in EPIC PN Hardness Ratio 1 float nullable pn_hr2 EPIC PN Hardness Ratio 2 float nullable source_type Classification of X-Ray Source src.class char nullable pn_hr3_error Error in EPIC PN Hardness Ratio 3 float nullable pn_hr1 EPIC PN Hardness Ratio 1 float nullable m2_hr2_error Error in EPIC MOS2 Hardness Ratio 2 float nullable m2_count_rate EPIC MOS2 Count Rate ct/s double nullable pn_hr3 EPIC PN Hardness Ratio 3 float nullable m2_hr1_error Error in EPIC MOS2 Hardness Ratio 1 float nullable source_number Source Number meta.id short nullable m1_count_rate_error Error in EPIC MOS1 Count Rate ct/s double nullable hr3 Combined EPIC Hardness Ratio 3 float nullable m2_hr2 EPIC MOS2 Hardness Ratio 2 float nullable hr1_error Error in Combined EPIC Hardness Ratio 1 float nullable m2_exposure Exposure of EPIC MOS2 Instrument (s) s double nullable m2_count_rate_error Error in EPIC MOS2 Count Rate ct/s double nullable m1_hr4 EPIC MOS1 Hardness Ratio 4 float nullable pn_flux EPIC PN Flux (erg/s/cm^2) erg/s/cm^2 double nullable m1_hr3 EPIC MOS1 Hardness Ratio 3 float nullable hr2_error Error in Combined EPIC Hardness Ratio 2 float nullable pn_count_rate_error Error in EPIC PN Count Rate ct/s double nullable m1_exposure Exposure of EPIC MOS1 Instrument (s) s double nullable hr1 Combined EPIC Hardness Ratio 1 float nullable other_remarks Additional Remarks char nullable m1_hr2_error Error in EPIC MOS1 Hardness Ratio 2 float nullable m2_hr4_error Error in EPIC MOS2 Hardness Ratio 4 float nullable b2_mag B2 Magnitude of Source USNO-B1.0 mag float nullable log_fx_fopt Logarithm of fX/fopt float nullable m1_count_rate EPIC MOS1 Count Rate ct/s double nullable i2_mag I2 Magnitude of Source USNO-B1.0 mag float nullable m2_hr3_error Error in EPIC MOS2 Hardness Ratio 3 float nullable m2_flux_error Error in EPIC MOS2 Flux erg/s/cm^2 double nullable hr3_error Error in Combined EPIC Hardness Ratio 3 float nullable number_usno_corr Number of USNO-B1.0 Correlations short nullable m1_hr3_error Error in EPIC MOS1 Hardness Ratio 3 float nullable m1_flux_error Error in EPIC MOS1 Flux erg/s/cm^2 double nullable m1_hr1_error Error in EPIC MOS1 Hardness Ratio 1 float nullable hr2 Combined EPIC Hardness Ratio 2 float nullable pn_hr4_error Error in EPIC PN Hardness Ratio 4 float nullable r2_mag R2 Magnitude of Source USNO-B1.0 mag float nullable m1_hr1 EPIC MOS1 Hardness Ratio 1 float nullable hr4_error Error in Combined EPIC Hardness Ratio 4 float nullable m1_det_ml EPIC MOS1 Source Detection Likelihood double nullable pn_hr4 EPIC PN Hardness Ratio 4 float nullable m2_hr1 EPIC MOS2 Hardness Ratio 1 float nullable m2_flux EPIC MOS2 Flux (erg/s/cm^2) erg/s/cm^2 double nullable m2_hr4 EPIC MOS2 Hardness Ratio 4 float nullable bii Galactic Latitude degree pos.galactic.lat double nullable m2_hr3 EPIC MOS2 Hardness Ratio 3 float nullable det_instruments EPIC instruments contributing to source detection char nullable offset_usno_xmm Angular Offset from USNO-B1.0 Source to XMM Source (arcsec) arcsec float nullable m2_det_ml EPIC MOS2 Source Detection Likelihood double nullable alt_xray_id X-Ray Identification char nullable pn_exposure Exposure of EPIC PN Instrument (s) s double nullable m1_flux EPIC MOS1 Flux (erg/s/cm^2) erg/s/cm^2 double nullable m1_hr4_error Error in EPIC MOS1 Hardness Ratio 4 float nullable pn_flux_error Error in EPIC PN Flux erg/s/cm^2 double nullable det_ml Source Detection Likelihood (Combined EPIC) double nullable usno_cat_name Name of Brightest USNO-B1.0 (<I/284>) Source within Search Area char nullable m1_hr2 EPIC MOS1 Hardness Ratio 2 float nullable pn_hr2_error Error in EPIC PN Hardness Ratio 2 float nullable lii Galactic Longitude degree pos.galactic.lon double nullable pn_count_rate EPIC PN Count Rate ct/s double nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable