ROSAT/ESOClus. ivo://nasa.heasarc/reflex NASA/GSFC HEASARC Bohringer et al. 2026-05-29 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Cluster of Galaxies This table is the ROSAT-ESO Flux-Limited X-Ray (REFLEX) Galaxy Cluster Survey Catalog. The REFLEX Cluster Survey provides information on the X-ray properties, redshifts, and some identification details of clusters in the REFLEX sample. The catalog describes a statistically complete X-ray flux-limited sample of 447 galaxy clusters above an X-ray flux of 3 x 10<sup>-12</sup> erg/s/cm<sup>2</sup> (0.1 to 2.4 keV) in an area of 4.24 steradians in the southern sky. The cluster candidates were first selected by their X-ray emission in the ROSAT-All Sky Survey and subsequently spectroscopically identified in the frame of an ESO key program. Previously described tests have shown that the sample is more than 90% complete and there is a conservative upper limit of 9% on the fraction of clusters with a dominant X-ray contamination from AGN. This data set is at present the largest, statistically complete X-ray galaxy cluster sample. The sample forms the basis of several cosmological studies, one of the most important applications being the assessment of the statistics of the large-scale structure of the universe and the test of cosmological models. The X-ray luminosities and other distance-dependent cluster parameters are calculated for a Lambda cosmology with a Hubble Constant H<sub>0</sub> of 70 km/s/Mpc, Omega<sub>M</sub> of 0.3, and Omega<sub>Lambda</sub> of 0.7. The CDS version of this catalog contains an additional table (reflex50.dat) with these parameters calculated for an Einstein-de Sitter universe with H<sub>0</sub> = 50 km/s/Mpc, Omega<sub>M</sub> = 1.0, and Omega<sub>Lambda</sub> = 0.0. This table was created by the HEASARC in October 2004 based on CDS tables J/A+A/425/367/reflex70.dat and J/A+A/425/367/reflex.dat. This is a service provided by NASA HEASARC . 2004A&A...425..367B https://heasarc.gsfc.nasa.gov/W3Browse/all/reflex.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=reflex& GET text/xml 180 99999 true 355.0431 -85.1782 0.05 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=reflex GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_reflex&Action=More+Options&Action=Parameter+Search&ConeAdd=1 ROSAT 0.05 X-ray public reflex ROSAT-ESO Flux-Limited X-Ray (REFLEX) Galaxy Cluster Survey 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 count_rate Source Count Rate in the 0.5-2.0keV Band (Uncorrected for Missing Flux) ct/s phot.count;em.X-ray.soft double nullable flux Flux in the 0.1-2.4keV Band (Corrected for Tx, and K-Correction Effects) erg/s/cm^2 phot.flux;em.X-ray.soft double nullable flux_error Error in Corrected Flux erg/s/cm^2 stat.error;phot.flux;em.X-ray.soft double nullable redshift Redshift src.redshift double nullable lx X-Ray Luminosity Corrected for the Missing Flux Outside the Aperture (erg/s) erg/s phys.luminosity;em.X-ray.soft 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 aperture_ang_radius Aperture Angular Radius for the Count Rate Determination (arcmin) arcmin instr.param;instr.fov float nullable num_photons Number of Source Photons Detected in 0.5-2.0keV Band (Uncorr. for Missing Flux) phot.count;em.X-ray.soft float nullable lii Galactic Longitude degree pos.galactic.lon double nullable hardness_ratio_error 1-Sigma of the Hardness Ratio Value stat.error;phot.flux;arith.ratio;em.X-ray float nullable nominal_flux Nominal Flux in the 0.1-2.4keV Band (for Tx=5keV, z=0) erg/s/cm^2 phot.flux;em.X-ray.soft double nullable aperture_radius Source Count Rate Aperture Radius (Mpc) Mpc double nullable delta_hardness_ratio Deviation of Observed to Expected H.R. in Units of Sigma of Poisson Statistics sigma stat.value;phot.count;em.X-ray;arith.ratio float nullable note_flags Flags Indicate Different Analysis and Comments meta.code char nullable minimal_core_radius Minimal Core Radius Allowed within 2-Sigma Interval by Chi^2 Fit arcmin stat;phys.angSize;src float nullable num_z_galaxies Number of Member Galaxies Used for Redshift Determination meta.number;src.redshift short nullable lx_obs Luminosity Detected within the Measurement Aperture (erg/s) erg/s phys.luminosity;em.X-ray.soft double nullable log_point_src_prob Log10 Probability of the Source to be a Point Source stat.likelihood;phys.size float nullable nh_gal Absorbing Galactic Hydrogen Column Density in the Line-of-Sight (cm^-2) cm^-2 phys.columnDensity double nullable ref_redshift References for the Literature Redshift meta.ref;src.redshift char nullable bii Galactic Latitude degree pos.galactic.lat double nullable hardness_ratio Hardness Ratio: (H-S)/(H+S), H=0.5-2.0keV Count Rate, S=0.1-0.4keV Count Rate phot.flux;arith.ratio;em.X-ray float nullable alt_name Alternative Designation meta.id char nullable best_fit_core_radius Very Rough Estimate of the Core by Chi^2 Fit arcmin phys.angSize float nullable note_name Flag Indicates Naming Notation meta.code;src char nullable