GC47TUCCXO ivo://nasa.heasarc/gc47tuccxo NASA/GSFC HEASARC Heinke et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The authors have detected 300 X-ray sources within the half-mass radius (2.79') of the globular cluster 47 Tucanae in a deep (281 ks) Chandra exposure. They perform photometry and simple spectral fitting for our detected sources and construct luminosity functions, X-ray color-magnitude, and color-color diagrams. Eighty-seven X-ray sources show variability on timescales from hours to years. Thirty-one of the new X-ray sources are identified with chromospherically active binaries from the catalogs of Albrow and coworkers (2001, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/559/1060">CDS Catalog <J/ApJ/559/1060></a>). The authors estimate that the total number of neutron stars in 47 Tuc is of order 300, reducing the discrepancy between theoretical neutron star retention rates and observed neutron star populations in globular clusters. The data used in this paper are from the 2000 and 2002 Chandra observations of the globular cluster 47 Tuc. The 2000 observations, initially described in Grindlay et al. (2001, Science 292, 2290), were performed with the ACIS-I CCD array at the telescope focus, while the 2002 observations placed the back-illuminated ACIS-S aim point at the focus for maximum low-energy sensitivity. The authors combined the results from wavdetect source detection runs with a threshold probability of 1 x 10<sup>-5</sup>, in two energy bands (0.5 - 2.0 keV and 0.5 - 6.0 keV for the 2000 observations, and (0.3 - 2.0 keV and 0.3 - 6.0 keV for the 2002 observations), to make independent source lists for the 2000 and 2002 observations, given in Tables 2 and 3 of the reference paper, which have been combined in the present HEASARC table. A total of 146 sources were detected in this way in the 2000 observations (entries with dataset_year = 2000), while 300 sources were detected in the 2002 observations (dataset_year = 2002). A total of 143 of the sources were clearly detected in both observations, while only three of the sources from the 2000 observations were not detected in the 2002 observations. See also the related <a href="gc47tuccx2.html">2017 source catalog</a>. This table was created by the HEASARC in June 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/625/796">CDS Catalog J/ApJ/625/796</a> files table2.dat, table3.dat, and (part of) table5.dat. This is a service provided by NASA HEASARC . 2005ApJ...625..796H https://heasarc.gsfc.nasa.gov/W3Browse/all/gc47tuccxo.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=gc47tuccxo& GET text/xml 180 99999 true 6.02535417 -72.12373333 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=gc47tuccxo GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_gc47tuccxo&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 X-ray public gc47tuccxo 47 Tuc Globular Cluster Chandra X-Ray Point Source Catalog (2005 name IAU-Approved Source Designation (CXOGlb JHHMMSS.s+DDMMSS) meta.id;meta.main char nullable alt_name_1 Alternative Source Designation Based on Detection Number ([GHE2001] WNNN) meta.id char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable counts Background-Subtracted 0.5-4.5keV Counts ct phot;em.X-ray double nullable counts_pos_err Upper Limit 1-Sigma Error in Background-Subtracted 0.5-4.5keV Counts ct stat.error;phot;em.X-ray double nullable counts_neg_err Lower Limit 1-Sigma Error in Background-Subtracted 0.5-4.5keV Counts ct stat.error;phot;em.X-ray double nullable lx The 0.5-6.0keV Luminosity (erg/s) erg/s phys.luminosity;em.X-ray double nullable source_type Classification of the Source src.class char nullable source_type_flag Flag [?] Indicates Uncertainty in Source Type meta.code char 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 sb2_lx_neg_err Lower Limit 1-Sigma Error in 0.5-2.5keV Luminosity (erg/s) erg/s stat.error;phys.luminosity;em.X-ray.soft double nullable sb1_counts_neg_err Lower Limit 1-Sigma Error in Background-Subtracted 0.5-1.5keV Counts ct stat.error;phot;em.X-ray.soft double nullable exposure Exposure Time (s) s time.duration;obs.exposure double nullable alt_name_2 Another Alternative Source Designation meta.id char nullable radial_distance Distance from Cluster Center (arcsec) arcsec pos.angDistance short nullable source_number The WAVDETECT detection number ([GHE2001] WNNN in Simbad) (G1) meta.id short nullable hb_counts_pos_err Upper Limit 1-Sigma Error in Background-Subtracted 1.5-6keV Counts ct stat.error;phot;em.X-ray.medium double nullable lii Galactic Longitude degree pos.galactic.lon double nullable sb1_counts_pos_err Upper Limit 1-Sigma Error in Background-Subtracted 0.5-1.5keV Counts ct stat.error;phot;em.X-ray.soft double nullable note_flags Flags Indicates Variability or Confusion Notes meta.code char nullable hb_counts Background-Subtracted 1.5-6keV Counts ct phot;em.X-ray.medium double nullable ra_error 1-Sigma Error in Right Ascension (s) s stat.error;pos.eq.ra;meta.main double nullable class Browse Object Classification src.class short nullable dec_error 1-Sigma Error in Declination (arcsec) arcsec stat.error;pos.eq.dec;meta.main double nullable dataset_year Dataset Year time.epoch short nullable hb_counts_neg_err Lower Limit 1-Sigma Error in Background-Subtracted 1.5-6keV Counts ct stat.error;phot;em.X-ray.medium double nullable psf_fraction PSF Fraction instr.det.psf double nullable sb1_counts Background-Subtracted 0.5-1.5keV Counts ct phot;em.X-ray.soft double nullable lx_neg_err Lower Limit 1-Sigma Error in 0.5-6.0keV Luminosity (erg/s) erg/s stat.error;phys.luminosity;em.X-ray double nullable sb2_lx_pos_err Upper Limit 1-Sigma Error in 0.5-2.5keV Luminosity (erg/s) erg/s stat.error;phys.luminosity;em.X-ray.soft double nullable bii Galactic Latitude degree pos.galactic.lat double nullable sb2_lx The 0.5-2.5keV Luminosity (erg/s) erg/s phys.luminosity;em.X-ray.soft double nullable lx_pos_err Upper Limit 1-Sigma Error in 0.5-6.0keV Luminosity (erg/s) erg/s stat.error;phys.luminosity;em.X-ray double nullable