J/A+A/712/A74ivo://CDS.VizieR/J/A+A/712/A74CDSVeronese S.de Blok W.J.G.Brinks E.Kleiner D.Kurapati S.Healy J.,Maccagni F.M.2026-08-05T08:43:11Z2026-08-05T09:42:43ZCDS support team

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

cds-question@unistra.frgalaxiesradio-astronomyh-i-line-emissionGalaxy discs have a finite extent, yet how and where their neutral atomic hydrogen (HI) components end is not fully understood. The existence of a break in the HI disc at column densities of ~10^+19^cm^-2^ has been debated since early 21-cm observations of the spiral galaxy NGC 3198. We present the HI radial profiles of 16 star-forming, late-type galaxies from the MeerKAT HI Observations of Nearby Galactic Objects: Observing Southern Emitters (MHONGOOSE) survey spanning a range of HI mass from 10^+7^M_{sun}_ to 10^+10^M_{sun}_. We probed via spectral stacking their HI discs down to inclination-corrected column densities of a few times 10^+17^cm^-2^ at kpc resolution. The HI radial profiles of high-mass (MHI>10^+9^M_{sun}_) galaxies are characterised by a inner plateau, followed by a knee at column densities of ~5x10^+20^cm^-2^, but no edges are unambiguously identified. The HI radial profiles of low-mass (MHI<10^+9^M_{sun}-) galaxies shows a steeper decline and also no edges. We found that the profiles are self-similar when normalised to the radius at which a mass surface density of 0.01M_{sun}_/pc^2^ is reached, in agreement with recent literature results, but we also found a possible correlation between the normalisation radius and the environment, suggesting that environment contributes to the shaping of the HI distribution in galaxies. The emerging picture is that the diverse morphology of the HI radial profiles is difficult to interpret, and future studies with a larger sample are necessary for quantifying the contribution of internal and external processes acting at different levels for different galaxies.2026A&A...712A..74Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/712/A74CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/73 : HI Parkes All Sky Survey Catalogue (HIPASS) (Meyer+, 2004)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/712/A74https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/712/A74http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/712/A74https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/712/A74https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/712/A74http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/712/A74GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/712/A74/table1 (Basic properties of the MHONGOOSE galaxies in our sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/712/A74/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/712/A74/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/712/A74/table1?GETtext/xml+votable180.050000true2.0556667-34.57833330.0055555555555555566/16414 16441 16687 21026 24912 25077 25318 33920 33958 34476 34478 34501 35746 36131 43972 46491https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/712/A74?format=asciiRadiodefaultJ/A+A/712/A74/table1Basic properties of the MHONGOOSE galaxies in our sampleSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHIPASSHIPASS name (JHHMM+DD)meta.id;meta.maincharNameNamemeta.idcharRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainDistDistanceMpcpos.distancefloatlog(MHI)HI masslog(solMass)phys.massfloatinclInclination angle (1)degsrc.orbital.inclinationintlog(M*)Stellar masslog(solMass)phys.massfloatlog(SFR)Star formation ratelog(solMass.yr**-1)phys.SFRfloatJ/A+A/712/A74/profilesHI profiles of the 16 sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHIPASSHIPASS name (JHHMM+DD) (HIPASS)meta.id;meta.maincharRaddegGalactocentric radius (radius_deg)degphys.angSize;pos.galactocentricfloatProfs150-180? Inclination-corrected radial profile from sector 150-180 deg (profile_s150_180)1e+19cm**-2phys.columnDensityfloatnullableProfs180-210? Inclination-corrected radial profile from sector 180-210 deg (profile_s180_210)1e+19cm**-2phys.columnDensityfloatnullableProfs210-240? Inclination-corrected radial profile from sector 210-240 deg (profile_s210_240)1e+19cm**-2phys.columnDensityfloatnullableProfs240-270? Inclination-corrected radial profile from sector 240-270 deg (profile_s240_270)1e+19cm**-2phys.columnDensityfloatnullableProfs270-300? Inclination-corrected radial profile from sector 270-300 deg (profile_s270_300)1e+19cm**-2phys.columnDensityfloatnullableProfs300-330? Inclination-corrected radial profile from sector 300-330 deg (profile_s300_330)1e+19cm**-2phys.columnDensityfloatnullableProfs330-360? Inclination-corrected radial profile from sector 330-360 deg (profile_s330_360)1e+19cm**-2phys.columnDensityfloatnullableProfStackClean? Clean inclination-corrected radial profile from stacking (profile_stack_clean)1e+19cm**-2phys.columnDensityfloatnullablee_ProfStackClean? Error on clean inclination-corrected radial profile from stacking (e_profile_stack_clean)1e+19cm**-2stat.errordoublenullableRadkpcGalactocentric radius (radius_kpc)kpcphys.size.radiusfloatProfMom0? Global inclination-corrected radial profile from moment 0 (profile_mom0)1e+19cm**-2phys.columnDensityfloatnullablee_ProfMom0? Error on global inclination-corrected radial profile from moment 0 (e_profile_mom0)1e+19cm**-2stat.errorfloatnullableProfStackGlobal inclination- corrected radial profile from stacking (profile_stack)1e+19cm**-2phys.columnDensityfloatFillFactorRing filling factor (fill_factor)stat.fit.paramfloatProfs0-30? Inclination-corrected radial profile from sector 0-30 deg (profile_s0_30)1e+19cm**-2phys.columnDensityfloatnullableProfs30-60? Inclination-corrected radial profile from sector 30-60 deg (profile_s30_60)1e+19cm**-2phys.columnDensityfloatnullableProfs60-90? Inclination-corrected radial profile from sector 60-90 deg (profile_s60_90)1e+19cm**-2phys.columnDensityfloatnullableProfs90-120? Inclination-corrected radial profile from sector 90-120 deg (profile_s90_120)1e+19cm**-2phys.columnDensityfloatnullableProfs120-150? Inclination-corrected radial profile from sector 120-150 deg (profile_s120_150)1e+19cm**-2phys.columnDensityfloatnullable