J/A+A/661/A4ivo://CDS.VizieR/J/A+A/661/A4doi:10.26093/cds/vizier.36610004CDSKlein M.Oguri M.Mohr J.J.Grandis S.Ghirardini V.Liu T.Liu A.,Bulbul E.Wolf J.Comparat J.Ramos-Ceja M.E.Buchner J.Chiu I.,Clerc N.Merloni A.Miyatake H.Miyazaki S.Okabe N.Ota N.,Pacaud F.Salvato M.Driver S.P.2024-10-21T20:01:33Z2022-05-18T13:09:27ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frgalaxy-clustersredshiftedx-ray-sourcessurveysIn 2019, the eROSITA telescope on board of the Russian-German satellite Spectrum-Roentgen-Gamma (SRG), has started to perform a deep all-sky X-ray survey with the aim of identifying ~100000 clusters and groups over the course of four years. As part of its performance verification phase a ~140deg^2^ survey called eROSITA Final Equatorial-Depth Survey (eFEDS) was performed. With a depth typical of the all-sky survey after four years, it allows tests of tools and methods as well as improved predictions for the all-sky survey. As part of this effort, a catalog of 542 X-ray extent selected galaxy group and cluster candidates was constructed. In this paper we present the optical follow-up with the aim of providing redshifts and cluster confirmation for the full sample. Further we aim to provide additional information on cluster dynamical state, cluster richness and cluster optical center. Finally we aim to evaluate the impact of optical cluster confirmation on the purity and completeness of the X-ray selected sample. We use optical imaging data from the Hyper Suprime-Cam Subaru Strategic Program and from the Legacy Survey to identify optical counterparts to the X-ray detected cluster candidates. We make use of the red sequence based cluster redshift and confirmation tool MCMF as well as the optical cluster finder CAMIRA to derive cluster redshifts and richnesses. MCMF provided probabilities of an optical structure being a chance super position with the X-ray candidate is used to identify the best optical counter part as well as to confirm an X-ray candidate as a cluster. The impact of this confirmation process on catalog purity and completeness is estimated using optical to X-ray scaling relations as well as simulations. The resulting catalog is further matched with public group and cluster catalogs. Optical estimators of cluster dynamical state are constructed based on density maps of the red sequence galaxies at the cluster redshift. While providing redshift estimates for all 542 candidates, we construct an optically confirmed sample of 477 clusters and groups with a residual contamination of 6%. Of these, 470 (98.5%) are confirmed using MCMF, and 7 systems are added through cross matching with spectroscopic group catalogs. Using observable to observable scaling and the applied confirmation threshold, we predict 8+/-2 real systems have been excluded with the MCMF cut required to build this low contamination sample. This number is in good agreement with the 7 systems found through cross matching that were not confirmed with MCMF. The predicted redshift and mass distribution of this catalog is in good agreement with simulations. Thus, we expect those 477 systems to include >99% of all true clusters in the candidate list. Using an MCMF independent method, we confirm the catalog contamination of the confirmed subsample to be 6+/-3%. Applying the same method to the full candidate list yields 17+/-3%, consistent with estimates coming from the fraction of confirmed systems of ~17% and expectations from simulations of ~20%. We further present a sample of merging cluster candidates based on the derived estimators of cluster dynamical state.2022A&A...661A...4Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/661/A4CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/474/3324 : Multicomponent matched filter test (Klein+, 2018)J/MNRAS/488/739 : MARD-Y3 catalog (Klein+, 2019)J/A+A/661/A1 : The eFEDS X-ray catalogs (V7.4) (Brunner+, 2022)J/A+A/661/A2 : Galaxy clusters and groups in eFEDS (Liu+, 2022)J/A+A/661/A3 : eFEDS counterparts to point-like sources (Salvato+, 2022)J/A+A/661/A5 : The eFEDS AGN catalog (Liu+, 2022)J/A+A/661/A7 : X-ray properties of eFEDS clusters and groups (Bahar+, 2022)J/A+A/661/A8 : eFEDS catalogue of variable X-ray sources (Boller+, 2022)J/A+A/661/A10 : eFEDS galaxy clusters and groups in disguise (Bulbul+, 2022)J/A+A/661/A23 : Exoplanet X-ray irradiation & evaporation rates (Foster+, 2022)J/A+A/661/A24 : Corona-chromosphere connection (Fuhrmeister+, 2022)J/A+A/661/A29 : First eROSITA study of nearby M dwarfs (Magaudda+, 2022)J/A+A/661/A34 : eta Cha cluster eROSITA X-ray scan (Robrade+, 2022)J/A+A/661/A35 : eROSITA study of 47 Tuc globular cluster (Saeedi+, 2022)J/A+A/661/A38 : SRG/ART-XC 1st year all-sky X-ray survey (Pavlinsky+, 2022)J/A+A/661/A40 : eRASS1 X-ray sources Sco-Cen members (Schmitt+, 2022)J/A+A/661/A44 : A first eROSITA view of ultracool dwarfs (Stelzer+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/661/A4https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/661/A4http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/661/A4https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/661/A4https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/661/A4http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/661/A4GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/661/A4/catalog (Cluster catalog with MCMF entries)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/661/A4/catalog?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/661/A4/catalog?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/661/A4/catalog?GETtext/xml+votable180.050000true144.303573.281040.0055555555555555564/256 1367 1707 5/1028-1029 1032 5459-5460 5462-5463 5465 6819 6822 6827 6842 10239 6/4120-4122 4124 4134-4138 4160-4161 4224 21830-21831 21833 21835 21844 21846-21847 21859 21869 21972-21973 27269 27271 27274-27275 27280 27282-27283 27286 27292 27294-27298 27300 27302-27305 27307 27336 27338-27339 27360-27362 27364 27372 40951 40953-40955https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/661/A4?format=asciiX-raydefaultJ/A+A/661/A4/catalogCluster catalog with MCMF entriesID-SRCSource ID of detection pipeline (ID_SRC)meta.idintMaskFrR500FootFraction of the area not in the optical footprint within a 3 arcmin radius but for a r_500 sized region (MASKFRAC_R500_FOOT_BEST_COMB)phys.angSizedoubleFcontP2LSfcont of the second peak (F_CONT_P2_LS)phot.fluxdoubleFcontP3LSfcont of the third peak (F_CONT_P3_LS)phot.fluxdoubleDeltaLFCLSDifference in f_cont between best and 2nd best counter part (DELTA_LFC_LS)phot.fluxdoubleSimbadSimbad column added by the CDSmeta.ref.urlchare_lambdaBest[] Uncertainty richness (ELAMBDA_BEST_COMB)stat.errorfloatSurvBest[-1/2] Survey used (SURV_BEST_COMB) (1)instr.setupintRAOdegRight ascension of optical center of best counter part (J2000) (RA_OPTCEN_BEST_COMB)degpos.eq.raDEOdegDeclination of optical center of best counter part (J2000) (DEC_OPTCEN_BEST_COMB)degpos.eq.deczspBestSpectrscopic redshift (SPEC_Z_BEST_COMB)src.redshift;pos.heliocentricdoubleo_zspBestNumber of redshifts used for spec-z (N_SPEC)meta.numberintMProxBestApprox. M500 used for richness estimate [1/h] (MASSPROX_BEST_COMB)phys.massdoubleFcont2BestSecond best f_cont of best optical counter part: -1, -2 for manually added systems (F_CONT_2BEST_COMB)phot.fluxdoublez2BestSecond Photometric redshift of best counter part (Z_2BEST_COMB)src.redshift.photdoublelambda2BestSecond Richness of best counter part (LAMBDA_2BEST_COMB)src.class.richnessfloate_lambda2BestSecond Uncertainty richness (ELAMBDA_2BEST_COMB)stat.errorfloate_z2BestSecond Uncertainty of the photometric redshift (SIGMA_Z_2BEST_COMB)stat.errorfloatSurv2Best[0/2] Second Survey used (SURV_2BEST_COMB) (1)meta.idintMProx2BestSecond bApprox. M500 used for richness estimate [1/h] (MASSPROX_2BEST_COMB)phys.massdoubleFlagO-XposValue of the optical footprint map at X-ray position (FLAG_OPTICAL_X_POS)meta.code.errorintMaskFr3FootFraction of the area not in the optical footprint within a 3 arcmin radius (MASKFRAC_3_FOOT)phys.angSizedoubleMaskFrFlgFraction of the area not in the optical footprint within a 3 arcmin radius but including flagged area due to bright star masks (MASKFRAC_3_FLAGGED)phys.angSizedoubleFcontP1LSfcont of the first peak (F_CONT_P1_LS)phot.fluxdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension of the X-ray center (J2000) (RA_CORR)degpos.eq.ra;meta.mainDEJ2000Declination of the X-ray center (J2000) (DEC_CORR)degpos.eq.dec;meta.mainePosPositional uncertainty (RADEC_ERR_CORR)arcsecstat.error;posdoubleExtSource extent in X-ray (EXT)arcsecphys.angSizedoublee_Ext[] Error in source extent (EXT_ERR)arcsecstat.errordoubleExtLikeExtent likelihood (EXT_LIKE)stat.likelihooddoubleMLCTSource counts (ML_CTS)ctphot.count;em.X-raydoublee_MLCT[] Error on counts (ML_CTS_ERR)ctstat.errordoubleMLRateCount rate (ML_RATE)ct/sphot.count;em.X-raydoublee_MLRate[] Error on count rate (ML_RATE_ERR)ct/sstat.errordoubleMLFluxSource flux (ML_FLUX)phot.flux;em.X-raydoublee_MLFluxError on flux (ML_FLUX_ERR)stat.errordoubleDetLikeDetection likelihood (DET_LIKE)stat.likelihooddoubleMLBkgBackground (ML_BKG)instr.backgrounddoubleMLExpTimeExposure time (ML_EXP)time.duration;obs.exposuredoubleINAREA90[FT] Label for column 18 (INAREA90)meta.codecharFcontBestfcont of best optical counter part: -1, -2 for manually added systems (F_CONT_BEST_COMB)phot.fluxdoublezBestPhotometric redshift of best counter part (Z_BEST_COMB)src.redshift.photfloate_zBest? Uncertainty of the photometric redshift (SIGMA_Z_BEST_COMB)stat.errorfloatnullablelambdaBestRichness of best counter part (LAMBDA_BEST_COMB)src.class.richnessfloatMaskFrR500FlgFraction of the area not in the optical footprint within a 3 arcmin radius but for a r_500 sized region (MASKFRAC_R500_FLAGGED_BEST_COMB)phys.angSizedoubleMaskFrR500Foot2Fraction of the area not in the optical footprint within a 3 arcmin radius for 2nd best counter part (MASKFRAC_R500_FOOT_2BEST_COMB)phys.angSizedoubleMaskFrR500Flg2Fraction of the area not in the optical footprint within a 3 arcmin radius but including flagged area due to bright star masks but for 2nd best counter part (MASKFRAC_R500_FLAGGED_2BEST_COMB)phys.angSizedoubleRAGdegRight ascension of galaxy density map based centre (J2000) (RA_GDMAP_BEST_COMB)degpos.eq.raDEGdegDeclination of galaxy density map based centre (J2000) (DEC_GDMAP_BEST_COMB)degpos.eq.decRAG2degRight ascension of galaxy density map based centre for 2nd best counterpart (J2000) (RA_GDMAP_2BEST_COMB)degpos.eq.raDEG2degDeclination of galaxy density map based centre for 2nd best counterpart (J2000) (DEC_GDMAP_2BEST_COMB)degpos.eq.decRABdegRight ascension of best BCG candidate (J2000) (RA_BCG_BEST_COMB)degpos.eq.raDEBdegDeclination of best BCG candidate (J2000) (DEC_BCG_BEST_COMB)degpos.eq.decalpha? Dynamical state estimator alpha (ALPHA)stat.fit.paramdoublenullabledelta? Dynamical state estimator delta (DELTA)stat.fit.paramdoublenullablebeta? Dynamical state estimator beta (BETA)stat.fit.paramdoublenullableellip? Dynamical state estimator: model ellipticity (ELLIP)stat.fit.paramdoublenullableCenterShift? Shift of the centre of the 2D density model with respect to X-ray position (CENTERSHIFT)obs.paramdoublenullableDistNOR500? Distance to next optical structure in the galaxy density map (DIST_NEXT_OPT_R500)pos.distancedoublenullableDistNX? Distance to next extent selected eFEDS cluster in MPC (DISTNEXT_XCLUST_MPC)Mpcpos.distancedoublenullableDistNXR500? Distance to next extent selected eFEDS cluster (DISTNEXT_XCLUST_R500)pos.distancedoublenullableFcontLFCLSfcont of best optical counter part of individual MCMF run using legacy survey (F_CONT_LFC_LS)phot.fluxdoublezLFCLSCorresponding redshift (Z_LFC_LS)src.redshift.photdoublelambdaLFCLSCorresponding richness (LAMBDA_LFC_LS)src.class.richnessdoublee_lambdaLFCLS[] Uncertainty of the richness (ELAMBDA_LFC_LS)stat.errordoublezP1LSRedshift of first peak in lambda versus redshift plot (Z_P1_LS)src.redshift.photdoublezP2LSRedshift of second peak in lambda versus redshift plot (Z_P2_LS)src.redshift.photdoublezP3LSRedshift of third peak in lambda versus redshift plot (Z_P3_LS)src.redshift.photdoublelambdaP1LSRichness of first peak (LAMBDA_P1_LS)src.class.richnessdoublelambdaP2LSRichness of second peak (LAMBDA_P2_LS)src.class.richnessdoublelambdaP3LSRichness of third peak (LAMBDA_P3_LS)src.class.richnessdoublee_lambdaP1LS[] Uncertainty on the richness of first peak (ELAMBDA_P1_LS)stat.errordoublee_lambdaP2LS[] Uncertainty on the richness of second peak (ELAMBDA_P2_LS)stat.errordoublee_lambdaP3LS[] Uncertainty on the richness of third peak (ELAMBDA_P3_LS)stat.errordoublee_zLFCLS? Uncertainty of the photometric redshift (SIGMA_Z_LFC_LS)stat.errordoublenullablee_zP1LS? Uncertainty of the photometric redshift of the 1st peak (SIGMA_Z_P1_LS)stat.errordoublenullablee_zP2LS? Uncertainty of the photometric redshift of the 2nd peak (SIGMA_Z_P2_LS)stat.errordoublenullablee_zP3LS? Uncertainty of the photometric redshift of the 3rd peak (SIGMA_Z_P3_LS)stat.errordoublenullableFcontLFCHSCf_cont of best optical counter part of individual MCMF run using HSC-SSP (HSC) (F_CONT_LFC_HSC)phot.fluxdoublezLFCHSCCorresponding redshift of best counter part in HSC (Z_LFC_HSC)src.redshift.photdoublelambdaLFCHSCRichness of first peak (LAMBDA_LFC_HSC)src.class.richnessdoublee_lambdaLFCHSC[] Uncertainty on the richness of first peak (ELAMBDA_LFC_HSC)stat.errordoublee_zLFCHSC? Uncertainty of the photometric redshift (SIGMA_Z_LFC_HSC)stat.errordoublenullablezP1HSCRedshift of first peak in lambda versus redshift plot (Z_P1_HSC)src.redshift.photdoublezP2HSCRedshift of second peak in lambda versus redshift plot (Z_P2_HSC)src.redshift.photdoublezP3HSCRedshift of third peak in lambda versus redshift plot (Z_P3_HSC)src.redshift.photdoublelambdaP1HSCRichness of first peak (LAMBDA_P1_HSC)src.class.richnessdoublelambdaP2HSCRichness of second peak (LAMBDA_P2_HSC)src.class.richnessdoublelambdaP3HSCRichness of third peak (LAMBDA_P3_HSC)src.class.richnessdoublee_lambdaP1HSC[] Uncertainty on the richness of first peak corresponding (ELAMBDA_P1_HSC)stat.errordoublee_lambdaP2HSC[] Uncertainty on the richness of second peak corresponding (ELAMBDA_P2_HSC)stat.errordoublee_lambdaP3HSC[] Uncertainty on the richness of third peak corresponding (ELAMBDA_P3_HSC)stat.errordoublee_zP1HSC? Uncertainty of the photometric redshift of the 1st peak (SIGMA_Z_P1_HSC)stat.errordoublenullablee_zP2HSC? Uncertainty of the photometric redshift of the 2nd peak (SIGMA_Z_P2_HSC)stat.errordoublenullablee_zP3HSCUncertainty of the photometric redshift of the 3rd peak (SIGMA_Z_P3_HSC)stat.errordoubleFcontP1HSCfcont of the first peak (F_CONT_P1_HSC)phot.fluxdoubleFcontP2HSCfcont of the second peak (F_CONT_P2_HSC)phot.fluxdoubleFcontP3HSCfcont of the third peak (F_CONT_P3_HSC)phot.fluxdoubleNameeROSITA source name (NAME)meta.id;meta.maincharMCMFNwaySec[12ABCD ] Sector in f_cont- p_any plane according to Sect. 5.4 (MCMF_NWAY_SECTOR)meta.codechar