J/A+A/681/A100ivo://CDS.VizieR/J/A+A/681/A100doi:10.26093/cds/vizier.36810100CDSJunais S.Weilbacher P.M.Epinat B.Boissier S.Galaz G.Johnston E.J.,Puzia T.H.Amram P.Malek K.2024-11-06T20:06:29Z2024-01-22T15:01:56ZCDS support team

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

cds-question@unistra.frgalaxy-clustersvisible-astronomyh-alpha-photometrychemical-abundancesradio-sourcesGiant low-surface brightness (GLSB) galaxies are an extreme class of objects with very faint and extended gas-rich disks. Malin 1 is the largest GLSB galaxy known to date, but its formation is still poorly understood. We use VLT/MUSE IFU spectroscopic observations of Malin 1 to reveal, for the first time, the presence of H{alpha} emission distributed across numerous regions along its disk, up to radial distances of ~100kpc. We made an estimate of the dust attenuation using the Balmer decrement and found that Malin 1 has a mean H{alpha} attenuation of 0.36mag. We observe a steep decline in the star formation rate surface density ({SIGMA}_SFR_) within the inner 20kpc, followed by a shallow decline in the extended disk. Similarly, the gas phase metallicity we estimated shows a steep gradient in the inner 20kpc, followed by a flattening of the metallicity in the extended disk with a relatively high value of ~0.6Z_{sun}_. We found that the normalized abundance gradient of the inner disk is similar to values found in normal galaxies but with an extreme value in the extended disk. A comparison of the star formation rate surface density and gas surface density shows that, unlike normal disk galaxies or other LSBs, Malin 1 exhibits a very low star formation efficiency. Owing to the detection of emission lines over a large part of the disk of Malin 1, this work sheds light on the star formation processes in this unique galaxy, highlighting its extended star-forming disk, dust attenuation, almost flat metallicity distribution in the outer disk, and exceptionally low star-formation efficiency. Our findings contribute to a more detailed understanding of the formation of the giant disk of Malin 1 and also constrain possible proposed scenarios on the nature of GLSB galaxies in general.2024A&A...681A.100Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/681/A100CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/593/A126 : Malin 1 images at 6 wavelengths (Boissier+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/681/A100https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/681/A100http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/681/A100https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/681/A100https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/681/A100http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/681/A100GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/681/A100/table1 (Properties of the H{alpha} selected regions in the extended disk of Malin 1)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/681/A100/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/681/A100/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/681/A100/table1?GETtext/xml+votable180.050000true189.24714.32870.005555555555555556Cone search capability for table J/A+A/681/A100/list (List of fits maps)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/681/A100/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/681/A100/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/681/A100/list?GETtext/xml+votable180.050000true189.2523214.330920.0055555555555555566/27942https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/681/A100?format=asciiOpticalRadiodefaultJ/A+A/681/A100/table1Properties of the H{alpha} selected regions in the extended disk of Malin 1recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRegionRegion IDmeta.id;obs.fieldintRAJ2000Right Ascension of region (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of region (J2000)degpos.eq.dec;meta.mainDistDistnace from the galaxy centerkpcpos.distancedoubleAreaArea of the regionarcsec**2phys.area;obs.fieldfloatHalphaHalpha surface brightness1e-20W.m**-2.arcsec**-2phot.flux;spect.linedoublee_HalphaHalpha surface brightness error1e-20W.m**-2.arcsec**-2stat.error;spect.linedoubleHa/Hb? Balmer ratiophys.abund;arith.ratiodoublenullablee_Ha/Hb? Balmer ratio errorstat.error;phys.abunddoublenullableN2? Metallicity N2 (12+logO/H)phys.abunddoublenullablee_N2? Metallicity (N2) errorstat.errordoublenullableO3N2? Metallicity O3N2(12+logO/H)phys.abunddoublenullablee_O3N2? Metallicity (O3N2) errorstat.errordoublenullableJ/A+A/681/A100/listList of fits mapsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameGalaxy namemeta.id;meta.maincharRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainscaleScale of the imagearcsec/pixinstr.scalefloatNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintsizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar