J/A+A/704/A264ivo://CDS.VizieR/J/A+A/704/A264CDSCabanillas de la Casa C.Hess K.M.Verdes-Montenegro L. Kotulla R.,Chen H.Jarrett T.H.Cluver M.E.De Daniloff S.B.,Gendron-Marsolais M.-L.Carignan C.Gallagher J.S. III,Kraan-Korteweg R.C.Ianjamasimanana R.2026-06-01T06:19:08Z2025-12-15T09:08:47ZCDS support team

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

cds-question@unistra.frgalaxy-clustersgalaxiesinfrared-photometryvisible-astronomybroad-band-photometryh-alpha-photometryabsolute-magnitudeStudying the impact of environment on star formation and quenching pathways requires statistically relevant samples of galaxies in a wide mass range. We present a new catalog of 196 galaxies of the nearby Hydra I cluster out to ~1.75r200, consisting of broad u,g,r,i,z along with narrowband H{alpha} measurements. These deep optical images were obtained with the DECam camera (CTIO) and reach down to a surface brightness limit of {mu}(3{sigma}; 10"x10")=26.9mag/arcsec^2^ in the g band. We also report the HI properties for 89 cluster members detected with MeerKAT. A color magnitude diagram (CMD) shows a bimodal distribution typical of a cluster population, more evolved than those found in isolation. We combine optical H{alpha} and WISE infrared data to compare the star formation history at two distinct timescales. Differences in the star forming activity depicted by both populations manifest as starburst in 24 found members. Of these, 18 starburst galaxies have neutral gas measurements, and show disturbed HI disks that suggest an environmentally triggered boost in star formation within the last 10^7^yrs. Processes such as ram pressure stripping or tidal interactions may underlie their enhanced star-forming activity and asymmetric disks. Since Hydra's dynamical history is unclear, we examine the spatial and velocity distribution of the sample. We reveal a possible link between the large scale structure feeding the Hydra I cluster and the heightened star-forming activity of the starburst galaxies. This feeding pattern matches the few substructure that has been identified in Hydra in previous works, and may explain its origin. Our results portray a picture of a cluster with an evolved nature, plus a population of new infalling galaxies that manifest the impact of their first contact with the cluster environment through star formation, color, morphology and gas content transformations.2025A&A...704A.264Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/704/A264CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/704/A264https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/704/A264http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/704/A264https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/704/A264https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/704/A264http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/704/A264GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/704/A264/tables12 (Catalog of 196 galaxies of the nearby Hydra I cluster out to ~1.75r200)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/704/A264/tables12?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/704/A264/tables12?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/704/A264/tables12?GETtext/xml+votable180.050000true159.1485833-27.518250.0055555555555555565/9691 9713 6/38763 38776 38778 38849 38851 38860-38861 38864 38866https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/704/A264?format=asciiOpticalInfrareddefaultJ/A+A/704/A264/tables12Catalog of 196 galaxies of the nearby Hydra I cluster out to ~1.75r200e_uMAGAbsolute value of the uncertainty in the absolute magnitude in DECam's u bandmagstat.errorfloatgMAGAbsolute value of absolute magnitude in DECam's g bandmagphys.magAbsfloate_gMAGAbsolute value of the uncertainty in the absolute magnitude in DECam's g bandmagstat.errorfloatrMAGAbsolute value of absolute magnitude in DECam's r bandmagphys.magAbsfloate_rMAGAbsolute value of the uncertainty in the absolute magnitude in DECam's r bandmagstat.errorfloatiMAG? Absolute value of absolute magnitude in DECam's i bandmagphys.magAbsfloatnullablee_iMAG? Absolute value of the uncertainty in the absolute magnitude in DECam's i bandmagstat.errorfloatnullablezMAG? Absolute value of absolute magnitude in DECam's z bandmagphys.magAbsfloatnullablee_zMAG? Absolute value of the uncertainty in the absolute magnitude in DECam's z bandmagstat.errorfloatnullableSFRHaStar Formation Rate from DECam's Halpha narrowbandlog(solMass.yr**-1)phys.SFRfloate_SFRHaUncertainty in the Star Formation Rate from DECam's Halpha narrowbandlog(solMass.yr**-1)stat.errorfloatlMAG[0/1] Upper limit (=1) flag for absolute magnitudesmeta.codeintl_SFRHa[0/1] Lower limit (=1) flag for SFRHameta.code.errorintflagStar[0/1] Bright source (=1) in the field that increases the uncertainty of the photometrymeta.code.errorintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDHydraSBGs catalog IDmeta.idintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainzRedshiftsrc.redshiftfloatuMAGAbsolute value of absolute magnitude in DECam's u bandmagphys.magAbsfloatSFRmIRStar Formation Rate from WISE surveysolMass/yrphys.SFRfloate_SFRmIR? Uncertainty in the Star Formation Rate from WISE surveysolMass/yrstat.errordoublenullablelogSmasslog10 of the stellar mass content from WISE surveylog(solMass)phys.massfloate_logSmassUncertainty of log10 of the stellar mass content from WISE surveylog(solMass)stat.errorfloatlogHImass? log10 of the neutral gas content from MeerKAT (if available)log(solMass)phys.massfloatnullablee_logHImass? Uncertainty of log10 of the neutral gas content from MeerKAT (if available)log(solMass)stat.errordoublenullableNameName of HydraSBGs galaxies from NEDmeta.id;meta.mainchar