NGC2264CXO ivo://nasa.heasarc/ngc2264cxo NASA/GSFC HEASARC Ramirez et al. 2026-10-02 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The NGC 2264 Chandra X-Ray Point Source Catalog contains the results of a Chandra observation of a field in the NGC 2264 star-forming region. The observation was made with Chandra's Advanced CCD Imaging Spectrometer imaging array (ACIS-I) on 2002 February 9, and has an exposure time of 48.1 ks. The catalog contains 263 sources, and includes X-ray luminosity, optical and infrared photometry, and X-ray variability information. The authors found 41 variable sources, 14 of which have a flare-like light curve, and two of which have a pattern of a steady increase or decrease over a 10-hr period. The optical and infrared photometry for the stars identified as X-ray sources are consistent with most of these objects being pre-main sequence stars with ages younger than 3 Myr. The authors found that 213 (81%) of the 263 X-ray sources have optical and/or infrared counterparts, most, but probably not all, of which are likely to be member stars of NGC 2264. There are 51 X-ray sources that lack optical or infrared counterparts: the authors believe that these are most likely extragalactic objects (active galaxies). This table was created by the HEASARC in February 2007 based on CDS table J/AJ/127/2659, files table1.dat, table4.dat and table5.dat. This is a service provided by NASA HEASARC . 2004AJ....127.2659R https://heasarc.gsfc.nasa.gov/W3Browse/all/ngc2264cxo.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=ngc2264cxo& GET text/xml 180 99999 true 100.11604167 9.68879639 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=ngc2264cxo GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_ngc2264cxo&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 Infrared Optical X-ray public ngc2264cxo NGC 2264 Chandra X-Ray Point Source Catalog name Chandra Source Designation (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 ctrpart_name Previously Published Designation char nullable vmag V-Band Magnitude mag phot.mag;em.opt.V double nullable count_rate Net Background- and Vignetting-Corrected Count Rate (ct/s) ct/s phot.count;em.X-ray double nullable flux X-ray Flux in Units of ergs/cm^2^/s erg/s/cm^2 phot.flux;em.X-ray double nullable log_lx Logarithm of the X-ray Luminosity in Units of ergs/s log(erg/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 rc_mag Cousins R-Band Magnitude mag double nullable alt_name Alternate Source Designation meta.id char nullable ic_mag Cousins I-Band Magnitude mag double nullable umag U-Band Magnitude mag phot.mag;em.opt.U double nullable alt_name_2 Sung et al. Catalog Designation meta.id char nullable dec_ctrpart Declination of Counterpart (J2000) char nullable hmag 2MASS or Rebull et al. H-band Magnitude mag double nullable exposure Effective Exposure Time (s) s time.duration;obs.exposure double nullable jmag_flag Flag [abc] for J-Band Magnitude char nullable jmag 2MASS or Rebull et al. J-Band Magnitude mag double nullable ra_ctrpart Right Ascension of Counterpart (J2000) char nullable ic_mag_flag Flag Indicates Cousins I-Band Photometry Contaminated by a Saturated Column char nullable source_number Chandra Source Identification Number meta.id short nullable off_axis Off-Axis Angle (arcmin) arcmin instr.offset double nullable kmag 2MASS or Rebull et al. K-Band Magnitude mag double nullable bii Galactic Latitude degree pos.galactic.lat double nullable lii Galactic Longitude degree pos.galactic.lon double nullable extraction_radius Count Extraction Radius (arcsec) arcsec double nullable vmag_flag Flag Indicates V-Band Photometry Contaminated by a Saturated Column char nullable prob_constant Constant-Source Probability percent short nullable hmag_flag Flag [ac] for H-band Magnitude char nullable psf_fraction Fraction of the PSF Enclosed double nullable alt_name_1 Rebull et al. Catalog Designation meta.id char nullable rc_mag_flag Flag Indicates Cousins R-Band Photometry Contaminated by a Saturated Column char nullable umag_flag Flag Indicates U-Band Photometry Contaminated by a Saturated Column char nullable bmag_flag Flag Indicates B-Band Photometry Contaminated by a Saturated Column char nullable bmag B-Band Magnitude mag phot.mag;em.opt.B double nullable kmag_flag Flag [ac] for K-band Magnitude char nullable alt_name_3 2MASS Designation meta.id char nullable comment_flags Additional Comments char nullable other_names Other Designations char nullable