Selected Hickson Compact Groups Chandra X-Ray Point Source Catalog

Selected Hickson Compact Groups Chandra X-Ray Point Source Catalog SELHCGCXO ivo://nasa.heasarc/selhcgcxo NASA/GSFC HEASARC Tzanavaris et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table contains the Chandra X-ray point source catalogs for 9 Hickson Compact Groups (HCGs, 37 galaxies) at distances of 34 to 89 Mpc. The authors perform detailed X-ray point source detection and photometry and interpret the point source population by means of simulated hardness ratios. They thus estimate X-ray luminosities (LX) for all sources, most of which are too weak for reliable spectral fitting. For all sources, they provide counts, count rates, power-law indices (Gamma), hardness ratios, and LX, in the full (0.5-8.0 keV), soft (0.5-2.0 keV) and hard (2-8 keV) bands. In their paper, the authors use optical emission-line ratios from the literature to re-classify 24 galaxies as star-forming, accreting onto a supermassive black hole (AGNs), transition objects, or low-ionization nuclear emission regions. Two-thirds of their galaxies have nuclear X-ray sources with Swift/UVOT counterparts. Two nuclei have full-band X-ray luminosities >= 1042 erg s-1, are strong multi-wavelength AGNs, and follow the known alphaOX - nu L_nu(near-UV)_ correlation for strong AGNs. Otherwise, most nuclei are X-ray faint, consistent with either a low-luminosity AGN or a nuclear X-ray binary population, and fall into the 'non-AGN' locus in alphaOX - nu L_nu(near-UV)_ space, which also hosts other normal galaxies. Each group was observed at the aim point of the back-illuminated S3 CCD of Chandra's Advanced CCD Imaging Spectrometer (ACIS), with the exception of HCG 90, which was observed with the ACIS-I array. The details of the 9 Chandra observations analyzed herein are given in Table 1 of the reference paper. The full details of the X-ray analysis and point source detection procedures are given in Section 3 of the reference paper. This table was created by the HEASARC in June 2014 based on electronic versions of Tables 2 and 3 from the reference paper which were obtained from the ApJS web site. Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC . 2014ApJS..212....9T https://heasarc.gsfc.nasa.gov/W3Browse/all/selhcgcxo.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=selhcgcxo& GET text/xml 180 99999 true 330.4448 -32.1073 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=selhcgcxo GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_selhcgcxo&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 X-ray public selhcgcxo Selected Hickson Compact Groups Chandra X-Ray Point Source Catal hcg_name Hickson Compact Group Identifier meta.id.assoc char nullable hcg_galaxy_id Identifier for the Galaxy in the Hickson Compact Group meta.id.assoc char nullable source_id Unique Source Identifier for Each Source in the Catalog meta.id;src char nullable 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 fb_count_rate Full 0.5-8 keV Band Count Rate ct/s phot.count;em.X-ray double nullable fb_count_rate_neg_err Lower Uncertainty for Full 0.5-8 keV Band Count Rate ct/s stat.error;phot.count;em.X-ray double nullable fb_count_rate_pos_err Upper Uncertainty for Full 0.5-8 keV Band Count Rate ct/s stat.error;phot.count;em.X-ray double nullable hardness_ratio Hardness Ratio phot.flux;arith.ratio;em.X-ray double nullable hardness_ratio_neg_err Lower Uncertainty for Hardness Ratio stat.error;phot.flux;arith.ratio;em.X-ray double nullable hardness_ratio_pos_err Upper Uncertainty for Hardness Ratio stat.error;phot.flux;arith.ratio;em.X-ray 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 ae_no_source_prob AE No-Source Probability stat.probability;em.X-ray double nullable fb_det_code Full Band Detection Code meta.code;src;em.X-ray short nullable fb_counts Full 0.5-8 keV Band Counts ct phot;em.X-ray int nullable log_sb_flux_error Uncertainty in Logarithm of Soft 0.5-2 keV Band Flux log(erg/s/cm^2) stat.error;phot.flux;em.X-ray.soft double nullable log_2_kev_flux Logarithm of Flux Density at 2 keV log(erg/s/cm^2/Hz) phot.flux.density;em.X-ray double nullable sb_count_rate_pos_err Upper Uncertainty for Soft 0.5-2 keV Band Count Rate ct/s stat.error;phot.count;em.X-ray.soft double nullable fb_counts_neg_err Lower Uncertainty for Full 0.5-8 keV Band Counts ct stat.error;phot;em.X-ray short nullable sb_count_rate Soft 0.5-2 keV Band Count Rate ct/s phot.count;em.X-ray.soft double nullable hardness_ratio_det_code Hardness Ratio Detection Code meta.code;src;em.X-ray short nullable fb_counts_pos_err Upper Uncertainty for Full 0.5-8 keV Band Counts ct stat.error;phot;em.X-ray short nullable log_sb_lx Logarithm of Soft 0.5-2 keV Band Luminosity log(erg/s) phys.luminosity;em.X-ray.soft double nullable lii Galactic Longitude degree pos.galactic.lon double nullable hb_count_rate_neg_err Lower Uncertainty for Hard 2-8 keV Band Count Rate ct/s stat.error;phot.count;em.X-ray.medium double nullable log_2_kev_flux_error Uncertainty in Logarithm of Flux Density at 2 keV stat.error;phot.flux.density;em.X-ray double nullable bii Galactic Latitude degree pos.galactic.lat double nullable sb_counts_pos_err Upper Uncertainty for Soft 0.5-2 keV Band Counts ct stat.error;phot;em.X-ray.soft short nullable ae_det_significance AE Detection Significance stat.probability;em.X-ray double nullable hb_counts Hard 2-8 keV Band Counts ct phot;em.X-ray.medium int nullable log_fb_lx Logarithm of Full 0.5-8 keV Band Luminosity log(erg/s) phys.luminosity;em.X-ray double nullable nuclear_flag Flag [YN] Indicates Nuclear Source meta.code char nullable log_hb_flux_error Uncertainty in Logarithm of Hard 2-8 keV Band Flux log(erg/s/cm^2) stat.error;phot.flux;em.X-ray.medium double nullable spectral_index_pos_err Upper Uncertainty for Power Law Spectral Index (Gamma) stat.error;spect.index double nullable hb_counts_neg_err Lower Uncertainty for Hard 2-8 keV Band Counts ct stat.error;phot;em.X-ray.medium short nullable log_fb_flux Logarithm of Full 0.5-8 keV Band Flux log(erg/s/cm^2) phot.flux;em.X-ray double nullable spectral_index Power Law Spectral Index (Gamma) spect.index double nullable log_sb_flux Logarithm of Soft 0.5-2 keV Band Flux log(erg/s/cm^2) phot.flux;em.X-ray.soft double nullable log_hb_lx Logarithm of Hard 2-8 keV Band Luminosity log(erg/s) phys.luminosity;em.X-ray.medium double nullable hb_counts_pos_err Upper Uncertainty for Hard 2-8 keV Band Counts ct stat.error;phot;em.X-ray.medium short nullable sb_count_rate_neg_err Lower Uncertainty for Soft 0.5-2 keV Band Count Rate ct/s stat.error;phot.count;em.X-ray.soft double nullable log_hb_flux Logarithm of Hard 2-8 keV Band Flux log(erg/s/cm^2) phot.flux;em.X-ray.medium double nullable hb_det_code Hard Band Detection Code meta.code;src;em.X-ray.medium short nullable hb_count_rate_pos_err Upper Uncertainty for Hard 2-8 keV Band Count Rate ct/s stat.error;phot.count;em.X-ray.medium double nullable log_fb_flux_error Uncertainty in Logarithm of Full 0.5-8 keV Band Flux log(erg/s/cm^2) stat.error;phot.flux;em.X-ray double nullable spectral_index_neg_err Lower Uncertainty for Power Law Spectral Index (Gamma) stat.error;spect.index double nullable sb_counts Soft 0.5-2 keV Band Counts ct phot;em.X-ray.soft short nullable sb_det_code Soft Band Detection Code meta.code;src;em.X-ray.soft short nullable sb_counts_neg_err Lower Uncertainty for Soft 0.5-2 keV Band Counts ct stat.error;phot;em.X-ray.soft short nullable hb_count_rate Hard 2-8 keV Band Count Rate ct/s phot.count;em.X-ray.medium double nullable psf_fraction Encircled Energy Fraction by AE PSF at 1.5 keV instr.det.psf double nullable