J/A+A/699/A105ivo://CDS.VizieR/J/A+A/699/A105doi:10.26093/cds/vizier/bc-nv/lbafCDSAmrutha B.M.Haines C.P.Demarco R.Nonino M.Finoguenov A.Rescigno U.2026-08-03T06:55:16Z2025-07-02T08:08:15ZCDS support team

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

cds-question@unistra.frgalaxy-clustersgalaxiescatalogsredshiftedWe present a new wide-field spectroscopic survey of the galaxy cluster SMACS J0723.3-7327 at z~0.39, with the aim of mapping the large-scale structure around this massive cluster. We also aim to detect infalling galaxy groups in combination with XMM-Newton and eROSITA X-ray data, while studying the evolution and transformation of cluster galaxies out to ~2r_200_. We carried out new multi-slit spectroscopic observations of SMACS J0723-3-7327 with the IMACS f/2 instrument on the 6.5m Magellan-Baade telescope, obtaining spectra for 193 galaxies selected using deep near-infrared (NIR) photometry from the Galaxy Clusters at VIRCAM (GCAV) survey. We examined the infall pattern of galaxies in the caustic diagram out to ~2r_200_ and used it to identify 93 cluster members from our sample as being located within the caustic curves. Incorporating redshifts from previous studies of the cluster core, we produced a catalogue of 150 spectroscopically-confirmed cluster members. We measured a central cluster redshift of z=0.3910+/-0.0007 and a velocity dispersion of {sigma}_V_=1431+/-150km/s for galaxies within r_200_. We found sub-structures within the velocity distribution function and a filamentary structure passing SE-NW through the cluster, likely related to the highly elongated mass distribution and X-ray emission seen in the central regions of the cluster. Using an optical colour-colour separation, we determine the fraction of star-forming galaxies as a function of cluster-centric radius out to 5r_200_ using photometric data, finding it consistently lower compared to coeval field galaxies even at 5r_200_. We identified a number of clumps of red galaxies in the cluster infall regions, suggestive of infalling groups in which galaxies could be undergoing pre-processing, even if we were unable to detect any associated X-ray emission in the XMM or eROSITA data. This work confirms the dynamical complexity of cluster SMACS J0723.3-7327 and the surrounding large-scale structure, similar to that seen for other massive clusters at z~0.4. Further spectroscopic analyses across larger cluster-centric distances are essential to comprehensively assess the dynamical state of the cluster and investigate how environmental mechanisms influence star formation quenching in galaxies at varying radial distances.2025A&A...699A.105Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/699/A105CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/666/L9 : SMACS J0723.3-7327 first JWST observations (Caminha+, 2022)J/ApJ/940/L24 : JWST 7.7um sources in SMACS J0723.3-7327 field (Iani+, 2022)J/A+A/670/A96 : SMACS J0723.3-7327 eROSITA and Chandra images (Liu+, 2023)J/ApJ/946/L40 : Galaxies in JWST obs. of SMACS J0723.3-7327 (Langeroodi+, 2023)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/699/A105https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/699/A105http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/699/A105https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/699/A105https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/699/A105http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/699/A105GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/699/A105/table1 (Redshift catalogue for SMACS J0723.3-7327)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/699/A105/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/699/A105/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/699/A105/table1?GETtext/xml+votable180.050000true110.82689-73.454740.0055555555555555566/37394-373957.952274030004205e-20 1.0188844282367877e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/699/A105?format=asciidefaultJ/A+A/699/A105/table1Redshift catalogue for SMACS J0723.3-7327recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainrmagr-band magnitude (AB) of galaxymagphot.mag;em.opt.RdoublezSpectroscopic redshift of galaxysrc.redshiftdoublee_zUncertainty in the spectroscopic redshiftstat.error;src.redshiftdoubleType[Q SF *] Spectroscopic class, Q = Quiescent, SF = StarFormingsrc.classcharClMem[0/1] Cluster member (=1) or not (=0)meta.code.memberintq_zQuality of spectroscopic redshiftmeta.code.qual;src.redshiftintKmagK-band magnitude (AB) of galaxymagphot.mag;em.IR.KdoubleJ-KJ-K colour (AB) of galaxymagphot.color;em.IR.J;em.IR.KdoublezphPhotometric redshiftsrc.redshiftdoublee_zphC Uncertainty in the photometric redshiftstat.errordouble