WD1CXO ivo://nasa.heasarc/wd1cxo NASA/GSFC HEASARC Clark et al. 2026-07-17 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The nature of the X-ray point source population within the young massive cluster Westerlund 1 (Wd 1) is investigated. Chandra X-ray Observatory (CXO) observations were used to determine the X-ray properties of emitters within Wd 1, while a comprehensive multi-wavelength dataset was employed to constrain their nature. Wd 1 (l=339.5, b=-0.4) was observed with the CXO Advanced CCD Spectrometer Spectroscopic array on 2005 May 22 for 18 ks (sequence 6283) and 2005 June 20 for 42 ks (sequence 5411). 241 sources were found above a sensitivity threshold that corresponded to a 10<sup>-6</sup> chance per PSF element of detecting a spurious source. X-ray emission from a multitude of different stellar sources within Wd 1, including both evolved high mass and low-mass pre-MS stars, is found. This table was created by the HEASARC in May 2008 based on CDS table J/A+A/477/147 files table1.dat and table3.dat. This is a service provided by NASA HEASARC . 2008A&A...477..147C https://heasarc.gsfc.nasa.gov/W3Browse/all/wd1cxo.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=wd1cxo& GET text/xml 180 99999 true 251.72249 -46.12304 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=wd1cxo GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_wd1cxo&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 X-ray public wd1cxo Westerlund 1 Chandra X-Ray Point Source Catalog name Catalog X-Ray Source Identifier, [CMN2008] JHHMMSS.s+DDMMSS 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 Uncertainty (arcsec) arcsec stat.error;pos double nullable photon_flux X-Ray Flux in the 0.5-8.0keV Band photon/cm^2/s phot.flux;em.X-ray double nullable counts Net Counts in the 0.5-8.0keV Band ct phot;em.X-ray double nullable counts_pos_err Error on Net Counts (Upper Limit) ct stat.error;phot;em.X-ray double nullable counts_neg_err Error on Net Counts (Lower Limit) ct stat.error;phot;em.X-ray double nullable optical_name Optical Designation meta.id.cross char nullable vmag V Magnitude mag phot.mag;em.opt.V 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 rmag R Magnitude mag phot.mag;em.opt.R double nullable imag I Magnitude mag phot.mag;em.opt.I double nullable source_flag Flag Indicates [i] Note on Source Name meta.code char nullable spect_type MK Spectral Type src.spType char nullable exposure Detector Live Time (s) s time.duration;obs.exposure double nullable opt_var_flag Flag Indicates [AEP] Variability Flag meta.code;src.var char nullable var_flag Flags [sl] Indicate Source Variability on Short or Long Timescales meta.code;src.var char nullable hardness_ratio_pos_err Error on Hardness Ratio (Upper Limit) stat.error;phot.flux;arith.ratio;em.X-ray double nullable bii Galactic Latitude degree pos.galactic.lat double nullable lii Galactic Longitude degree pos.galactic.lon double nullable bmag B Magnitude mag phot.mag;em.opt.B double nullable opt_ctrprt_flag Counterpart Flag meta.code;src;em.opt char nullable off_axis Angular Offset from the Aim Point of the Observation (arcmin) arcmin instr.offset double nullable hardness_ratio_neg_err Error on Hardness Ratio (Lower Limit) stat.error;phot.flux;arith.ratio;em.X-ray double nullable hardness_ratio Hardness Ratio phot.flux;arith.ratio;em.X-ray double nullable class Browse Object Classification src.class short nullable number_in_chart Number of the Source in the Finding Chart meta.number short nullable