J/A+A/670/A21ivo://CDS.VizieR/J/A+A/670/A21doi:10.26093/cds/vizier.36700021CDSJones M.G.Verdes-Montenegro L.Moldon J.Damas-Segovia A.Borthakur S.,Luna S.Yun M.S.del Olmo A.Perea J.Cannon J.Lopez Gutierrez D.,Cluver M.Garrido J.Sanchez S.2024-11-06T20:02:39Z2023-01-31T08:22:00ZCDS support team

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

cds-question@unistra.frgalaxiesspectroscopyh-i-line-emissionradio-astronomyHickson compact groups (HCGs) are dense configurations of four to ten galaxies, whose HI morphology appears to follow an evolutionary sequence of three phases, with gas initially confined to galaxies, then significant amounts spread throughout the intra-group medium, and finally with almost no gas remaining in the galaxies themselves. It has also been suggested that several groups may harbour a diffuse HI component that is resolved out by interferometric observations. The HI deficiency of HCGs is expected to increase as the HI morphological phase progresses along the evolutionary sequence. If this is the case, HI deficiency would be a rough proxy for the age and evolutionary state of a HCG. We aim to test this hypothesis for the first time using a large sample of HCGs and to investigate the evidence for diffuse HI in HCGs. We performed a uniform reduction of all publicly available VLA HI observations (38 HCGs) with a purpose-built pipeline that also maximises the reproducibility of this study. The resulting HI data cubes were then analysed with the latest software tools to perform a manual separation of emission features into those belonging to galaxies and those extending into the intra-group medium. We thereby classified the HI morphological phase of each group as well as quantified their HI deficiency compared to galaxies in isolation. We find little evidence that HI deficiency can be used as a proxy for the evolutionary phase of a compact group in either of the first two phases, with the distribution of HI deficiency being consistent in both. However, for the final phase, the distribution clearly shifts to high HI deficiencies, with more than 90% of the expected HI content typically missing. Across all HCGs studied, we identify a few cases where there is strong evidence for a diffuse gas component in the intra-group medium, which might be detectable with improved observations. We also classify a new sub-phase where groups contain a lone HI-bearing galaxy, but are otherwise devoid of gas. The new morphological phase we have identified is likely the result of an evolved, gas-poor group acquiring a new, gas-rich member. The large spread of HI deficiencies in the first two morphological phases suggests that there is a broad range of initial HI content in HCGs, which is perhaps influenced by large-scale environment, and that the timescale for morphological changes is, in general, considerably shorter than the timescale for the destruction or consumption of neutral gas in these systems.2023A&A...670A..21Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/670/A21CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/213 : Hickson's compact groups of Galaxies (Hickson+ 1982-1994)J/ApJ/821/113 : HCG and RSCG compact group galaxies with WISE (Zucker+ 2016)J/A+A/609/A17 : AMIGA XIII. HI properties (Jones+ 2018)J/A+A/632/A78 : A case study of the HI content of HCG 16 (Jones+ 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/670/A21https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/670/A21http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/670/A21https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/670/A21https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/670/A21http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/670/A21GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/670/A21/table1 (HCG HI sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/670/A21/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/670/A21/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/670/A21/table1?GETtext/xml+votable180.050000true7.875178.431260.005555555555555556Cone search capability for table J/A+A/670/A21/tablec1 (The HI content of Hickson Compact Groups)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/670/A21/tablec1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/670/A21/tablec1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/670/A21/tablec1?GETtext/xml+votable180.050000true7.849558.468220.005555555555555556Cone search capability for table J/A+A/670/A21/list (List of fits datacubes)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/670/A21/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/670/A21/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/670/A21/list?GETtext/xml+votable180.050000true7.874088.430120.0055555555555555566/2254 2276 4215 4966 5970 7532 8557 8935 8946 10637 13511 17492 17866 18071 18757 19538 19617 19619 19626 19661 20031 22772 22828 23182 24126 25769 27174 27620 27803 27872 28269 28278 28515 36621 36672 36713 36740 38853 46987 47027 49121https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/670/A21?format=asciiRadiodefaultJ/A+A/670/A21/table1HCG HI sampleSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHCG[1/100] HCG number (Cat. VII/213)meta.id;meta.mainintNmemb[2/8] Number of galaxies in groupmeta.numberintRAJ2000Group right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Group declination (J2000)degpos.eq.dec;meta.mainHRVGroup heliocentric radial velocitykm/sspect.dopplerVeloc;pos.lg;pos.heliocentricintDist[0/160] Group distance (1)Mpcpos.distanceintVLAConfigVLA configuration(s) the group was observed withinstr.setupcharDVChanChannel width of reduced VLA HI observationskm/sphys.velocfloatrmsRMS noise in reduced VLA HI cubemJy/beaminstr.det.noisefloatbeamMajMajor axis diameter of VLA synthesized beamarcsecphys.angSizefloatbeamMinMinor axis diameter VLA synthesized beamarcsecphys.angSize;instr.beamfloatNHI4-sigma HI column density sensitivity (over 20km/s)1e+19cm**-2phys.columnDensityfloatJ/A+A/670/A21/table2HI deficiency of HCGslogMHI-GBT? Logarithm of total group HI mass from GBT observations (Borthakur et al., 2010ApJ...710..385B)log(solMass)phys.massfloatnullablelogMHI-predLogarithm of predicted total group HI mass based on B-band luminosity (Jones et al., 2016MNRAS.457.4393J)log(solMass)phys.massfloatl_HIdef-VLA[>] Lower limit flag for HI deficiency from the VLAmeta.code.errorcharHIdef-VLAHI deficiency of group from VLA HI massphys.mass;arith.ratiofloatHIdef-GBT? HI deficiency of group from GBT HI massphys.mass;arith.ratiofloatnullablelogMHI-gals? Total HI mass in galaxies (VLA)log(solMass)phys.massfloatnullablelogMHI-exfs? Total HI mass in extended features (VLA)log(solMass)phys.massfloatnullablefexfs? Fraction of HI mass in extended features (VLA)phys.mass;arith.ratiofloatnullableHIphaseHI morphological phase (cf. Verdes-Montenegro et al., 2001A&A...377..812V)meta.code;src.morphcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHCG[2/100] HCG number (Cat. VII/213)meta.id;meta.mainintl_logMHI-VLA[<] Upper limit flag for HI mass from VLAmeta.code.errorcharlogMHI-VLALogarithm of total group HI mass from VLAlog(solMass)phys.massfloate_logMHI-VLA? Uncertainty in HI mass from VLAlog(solMass)stat.errorfloatnullableJ/A+A/670/A21/tablec1The HI content of Hickson Compact GroupsIRclassIR activity classification (Zucker et al., 2016ApJ...821..113Z, Cat. J/ApJ/821/113)meta.code.class;src.classcharHRVGalaxy heliocentric radial velocity (Hickson et al., 1992ApJ...399..353H, Cat. VII/213)km/sspect.dopplerVeloc;pos.heliocentricintBmagGalaxy B-band apparent magnitude (Hickson et al., 1989ApJS...70..687H, Cat. VII/213)magphot.mag;em.opt.Bfloate_BmagUncertainty in B-band apparent magnitudemagstat.error;phot.magfloatlogMHI-predLogarithm of predicted HI mass (Jones et al., 2018A&A...609A..17J, Cat. J/A+A/609/A17)log(solMass)phys.massfloate_logMHI-predUncertainty in predicted HI masslog(solMass)stat.errorfloatlogMHI? Logarithm of HI mass (VLA)log(solMass)phys.massfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHCG[2/100] HCG number (Cat. VII/213)meta.id;meta.mainintNameGalaxy namemeta.idcharRAJ2000Galaxy right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Galaxy declination (J2000)degpos.eq.dec;meta.mainMTypeGalaxy morphological type (Hickson et al., 1989ApJS...70..687H, Cat. VII/213)src.morph.typecharHIdef? Galaxy HI deficiency (VLA)phys.mass;arith.ratiofloatnullableJ/A+A/670/A21/listList of fits datacubesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHCG[2/100] HCG number (Cat. VII/213)meta.id;meta.mainintRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintNzNumber of pixels along Z-axismeta.numberintObs.dateObservation datestime.epoch;obsnullablebVRADLower value of VRAD intervalm/sphys.veloc;pos.heliocentricdoubleBVRADUpper value of VRAD intervalm/sphys.veloc;pos.heliocentricdoubledVRADVRAD resolutionm/sspect.resolutiondoublesizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar