J/A+A/610/A5ivo://CDS.VizieR/J/A+A/610/A5doi:10.26093/cds/vizier.36100005CDSComeron S.Salo H.Knapen J.H.2018-03-12T08:51:58Z2018-02-09T14:41:27ZCDS support team

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

cds-question@unistra.frgalaxiesinfrared-sourcesphotometryRecent studies have made the community aware of the importance of accounting for scattered light when examining low-surface-brightness galaxy features such as thick discs. In our past studies of the thick discs of edge-on galaxies in the Spitzer Survey of Stellar Structure in Galaxies - the S4G - we modelled the point spread function as a Gaussian. In this paper we re- examine our results using a revised point spread function model that accounts for extended wings out to more than 2.5arcmin. We study the 3.6micron images of 141 edge-on galaxies from the S4G and its early-type galaxy extension. Thus, we more than double the samples examined in our past studies. We decompose the surface-brightness profiles of the galaxies perpendicular to their mid-planes assuming that discs are made of two stellar discs in hydrostatic equilibrium. We decompose the axial surface- brightness profiles of galaxies to model the central mass concentration - described by a Sersic function - and the disc - described by a broken exponential disc seen edge-on. Our improved treatment fully confirms the ubiquitous occurrence of thick discs. The main difference between our current fits and those presented in our previous papers is that now the scattered light from the thin disc dominates the surface brightness at levels below ~26mag/arcsec^2^. We stress that those extended thin disc tails are not physical, but pure scattered light. This change, however, does not drastically affect any of our previously presented results: 1) Thick discs are nearly ubiquitous. They are not an artefact caused by scattered light as has been suggested elsewhere. 2) Thick discs have masses comparable to those of thin discs in low-mass galaxies - with circular velocities vc<120km/s - whereas they are typically less massive than the thin discs in high-mass galaxies. 3) Thick discs and central mass concentrations seem to have formed at the same epoch from a common material reservoir. 4) Approximately 50% of the up-bending breaks in face-on galaxies are caused by the superposition of a thin and a thick disc where the scale-length of the latter is the largest.2018A&A...610A...5Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/610/A5CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/93/255 : Axial ratios of edge-on spirals (Guthrie 1992)J/PAZh/27/250 : Rotation curves for 135 edge-on galaxies (Makarov+, 2001)J/A+A/389/795 : Vertical structure of edge-on galaxies (Bizyaev+, 2002)J/A+A/435/459 : HI data of edge-on spiral galaxies (Huchtmeier+, 2005)J/A+A/445/765 : A Catalog of Edge-on Disk Galaxies (Kautsch+, 2006)J/ApJ/702/1567 : Structure of 2MASS edge-on galaxies (Bizyaev+, 2009)J/ApJ/787/24 : Structural parameters of true edge-on galaxies (Bizyaev+ 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/610/A5https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/610/A5http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/610/A5https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/610/A5https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/610/A5http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/610/A5GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/610/A5/tableb (Galaxies with at least two distinct discs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/610/A5/tableb?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/610/A5/tableb?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/610/A5/tableb?GETtext/xml+votable180.050000true8.0088792-64.25347220.005555555555555556Cone search capability for table J/A+A/610/A5/tablec (Galaxies that do not have at least two distinct discs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/610/A5/tablec?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/610/A5/tablec?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/610/A5/tablec?GETtext/xml+votable180.050000true320.3178417-46.15283060.0055555555555555566/697 4279 4439 4565 5196 5396 5469 5482 5503 5599 5762 6012 7584 7662 8034 8129 8536 8646 10544 10628 10847 10888 10924 10979 11218 11259 11290 11389 11396 11450 11776 11824 11887 12004 12031 12633 16675 17777 18242 18326-18327 18427-18428 18755 18935 19310 19843 20080 23170 24733 24794 24949 24957 25172 25571 25635 25766 25769 25775 25959 26093 26265 26285 26301-26303 26311 26336 26362 26542 26660 26803 27079 27345 27347 27588 27718 27720 27725 27727 27750 27755 27763-27764 27766 27861 27913 27921 27931 27941 28038 28091 28126 28141 28184 28220 28294 28304 28491 28495 28529 31321 31340 31426 31628 33455 33950 33954 34260 34276 34400 34534 34539 34541 35913 36244 36338 36501 36598 36611 40438 43941-43942 44639 45205 45305 45405 45462 46363 46409 46520 46564 46722 46932 47008 47031https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/610/A5?format=asciiInfrareddefaultJ/A+A/610/A5/tablebGalaxies with at least two distinct discsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDGalaxy namemeta.id;meta.maincharr25Isophotal 25mag/arcsec^2^ radius in the B-band from HyperLedaarcsecphys.angSize;em.opt.BfloatPAMajot axis position angledegpos.posAngfloatM3.6Absolute 3.6um magnitude in the AB system (1)magphys.magAbs;em.IR.3-4umfloatDistGalaxy distanceMpcpos.distancefloatr_Dist[1/5] Source of the galaxy distance (2)meta.ref;pos.frameintvcGalaxy maximum circular velocitykm/sphys.velocintr_vc[1/19] Source of the galaxy maximum circular velocity (3)meta.ref;pos.frameintzc1? Lower limit of the region where most of the light is emitted by the thick discarcsecstat.fit.paramfloatnullablezc2? Higher limit of the region where most of the light is emitted by the thick discarcsecstat.fit.paramfloatnullablezuHeight where the surface brightness is 26mag/arcsec^2^arcsecstat.fit.paramfloatrCMC? Scale size of the central mass concentration (CMC)arcsecphys.angSize;srcfloatnullablenCMC? Sersic index of the central mass concentration (CMC)arcsecstat.fit.paramfloatnullableTtotAxial surface brightness profile type of the whole discmeta.notecharh1totScale-length of the first exponential section of the whole discarcsecphys.angSize;srcdoubleh2tot? Scale-length of the second exponential section of the whole discarcsecphys.angSize;srcdoublenullableh3tot? Scale-length of the third exponential section of the whole discarcsecphys.angSize;srcfloatnullableh4tot? Scale-length of the fourth exponential section of the whole discarcsecphys.angSize;srcfloatnullabler12tot? Radius of the break between the first and the second exponential sections of the whole discarcsecstat.fit.paramfloatnullabler23tot? Radius of the break between the second and the third exponential sections of the whole discarcsecstat.fit.paramfloatnullabler34tot? Radius of the break between the third and the fourth exponential sections of the whole discarcsecstat.fit.paramfloatnullableTthinAxial surface brightness profile type of the thin discmeta.notecharh1thin? Scale-length of the first exponential section of the thin discarcsecphys.angSize;srcdoublenullableh2thin? Scale-length of the second exponential section of the thin discarcsecphys.angSize;srcdoublenullableh3thin? Scale-length of the third exponential section of the thin discarcsecphys.angSize;srcfloatnullableh4thin? Scale-length of the fourth exponential section of the thin discarcsecphys.angSize;srcfloatnullabler12thin? Radius of the break between the first and the second exponential sections of the thin discarcsecstat.fit.paramfloatnullabler23thin? Radius of the break between the second and the third exponential sections of the thin discarcsecstat.fit.paramfloatnullabler34thin? Radius of the break between the third and the fourth exponential sections of the thin discarcsecstat.fit.paramfloatnullableTthickAxial surface brightness profile type of the thick discmeta.notecharh1thick? Scale-length of the first exponential section of the thick discarcsecphys.angSize;srcdoublenullableh2thick? Scale-length of the second exponential section of the thick discarcsecphys.angSize;srcfloatnullableh3thick? Scale-length of the third exponential section of the thick discarcsecphys.angSize;srcfloatnullabler12thick? Radius of the break between the first and the second exponential sections of the thick discarcsecstat.fit.paramfloatnullabler23thick? Radius of the break between the second and the third exponential sections of the thick discarcsecstat.fit.paramfloatnullableGasMGas disc mass1e+09solMassphys.massfloatThinMThin disc mass1e+09solMassphys.massfloatThickMThick disc mass1e+09solMassphys.massfloatCMCMCentral mass concentration (CMC) mass1e+09solMassphys.massfloatsc-thinThin disc scale-heightarcsecphys.angSize;srcfloatsc-thickThick disc scale-heightarcsecphys.angSize;srcfloatSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/A+A/610/A5/tablecGalaxies that do not have at least two distinct discsIDGalaxy namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintr25Isophotal 25mag/arcsec^2^ radius in the B-band from HyperLedaarcsecphys.angSize;em.opt.BfloatPAMajot axis position angledegpos.posAngfloatM3.6Absolute 3.6um magnitude in the AB system (1)magphys.magAbs;em.IR.3-4umfloatDistGalaxy distanceMpcpos.distancefloatr_Dist[1/5] Source of the galaxy distance (2)meta.ref;pos.frameintvcGalaxy maximum circular velocitykm/sphys.velocintr_vc[1/19] Source of the galaxy maximum circular velocity (3)meta.ref;pos.frameintzc1? Lower limit of the region where most of the light is emitted by the thick discarcsecstat.fit.paramfloatnullablezc2? Higher limit of the region where most of the light is emitted by the thick discarcsecstat.fit.paramfloatnullablezuHeight where the surface brightness is 26mag/arcsec^2^arcsecstat.fit.paramfloatrCMC? Scale size of the central mass concentration (CMC)arcsecphys.angSize;srcfloatnullablenCMC? Sersic index of the central mass concentration (CMC)arcsecstat.fit.paramfloatnullableTtotAxial surface brightness profile type of the whole discmeta.notecharh1totScale-length of the first exponential section of the whole discarcsecphys.angSize;srcdoubleh2tot? Scale-length of the second exponential section of the whole discarcsecphys.angSize;srcdoublenullableh3tot? Scale-length of the third exponential section of the whole discarcsecphys.angSize;srcfloatnullableh4tot? Scale-length of the fourth exponential section of the whole discarcsecphys.angSize;srcfloatnullabler12tot? Radius of the break between the first and the second exponential sections of the whole discarcsecstat.fit.paramfloatnullabler23tot? Radius of the break between the second and the third exponential sections of the whole discarcsecstat.fit.paramfloatnullabler34tot? Radius of the break between the third and the fourth exponential sections of the whole discarcsecstat.fit.paramfloatnullableTthinAxial surface brightness profile type of the thin discmeta.notecharh1thin? Scale-length of the first exponential section of the thin discarcsecphys.angSize;srcdoublenullableh2thin? Scale-length of the second exponential section of the thin discarcsecphys.angSize;srcdoublenullableh3thin? Scale-length of the third exponential section of the thin discarcsecphys.angSize;srcfloatnullableh4thin? Scale-length of the fourth exponential section of the thin discarcsecphys.angSize;srcfloatnullabler12thin? Radius of the break between the first and the second exponential sections of the thin discarcsecstat.fit.paramfloatnullabler23thin? Radius of the break between the second and the third exponential sections of the thin discarcsecstat.fit.paramfloatnullabler34thin? Radius of the break between the third and the fourth exponential sections of the thin discarcsecstat.fit.paramfloatnullableTthickAxial surface brightness profile type of the thick discmeta.notecharh1thick? Scale-length of the first exponential section of the thick discarcsecphys.angSize;srcdoublenullableh2thick? Scale-length of the second exponential section of the thick discarcsecphys.angSize;srcfloatnullableh3thick? Scale-length of the third exponential section of the thick discarcsecphys.angSize;srcfloatnullabler12thick? Radius of the break between the first and the second exponential sections of the thick discarcsecstat.fit.paramfloatnullabler23thick? Radius of the break between the second and the third exponential sections of the thick discarcsecstat.fit.paramfloatnullableGasMGas disc mass1e+09solMassphys.massfloatThinMThin disc mass1e+09solMassphys.massfloatThickMThick disc mass1e+09solMassphys.massfloatCMCMCentral mass concentration (CMC) mass1e+09solMassphys.massfloatsc-thinThin disc scale-heightarcsecphys.angSize;srcfloatsc-thickThick disc scale-heightarcsecphys.angSize;srcfloatSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main