J/ApJ/679/156ivo://CDS.VizieR/J/ApJ/679/156doi:10.26093/cds/vizier.16790156CDSHopkins P.F.Hernquist L.Cox T.J.Dutta S.N.Rothberg B.2017-12-22T05:32:13Z2010-10-07T11:00:43ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleigalaxy-classification-systemsabsolute-magnitudeWe study the origin and properties of "extra" or "excess" central light in the surface brightness profiles of remnants of gas-rich mergers. By combining a large set of hydrodynamical simulations with data on observed mergers that span a broad range of profiles at various masses and degrees of relaxation, we show how to robustly separate the physically meaningful extra light (i.e., the stellar population formed in a compact central starburst during a gas-rich merger) from the outer profile established by violent relaxation acting on stars already present in the progenitor galaxies prior to the final stages of the merger. This separation is sensitive to the treatment of the profile, and we demonstrate that certain fitting procedures can yield physically misleading results. We show that our method reliably recovers the younger starburst population, and examine how the properties and mass of this component scale with the mass, gas content, and other aspects of the progenitors. We consider the time evolution of the profiles in different bands, and estimate the biases introduced by observational studies at different phases and wavelengths. We show that, when appropriately quantified, extra light is ubiquitous in both observed and simulated gas-rich merger remnants, with sufficient mass (~3%-30% of the stellar mass) to explain the apparent discrepancy in the maximum phase-space densities of ellipticals and their progenitor spirals.2008ApJ...679..156Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/679/156CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/679/156https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/679/156http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/679/156https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/679/156https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/679/156http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/679/156GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/679/156/table1 (Fits to Rothberg & Joseph (RJ04, 2004AJ....128.2098R) merger remnants)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/679/156/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/679/156/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/679/156/table1?GETtext/xml+votable180.050000true29.958330.394720.0055555555555555566/226 2363 4188 4520 4993 5793 5980 5989 6034 6481 7552 7682 8024 8085 8562 9286 9310 10465 11180 11206 11938 12658 16058 16881 17183 17286 17819 18217 18714 20208 20230 20497 22519 22611 22721 24627 24855 24920 25136 28476 31372 36050 36226 38139 38829 43620 44551 46079 46296 46811 47078 47478https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/679/156?format=asciiOpticaldefaultJ/ApJ/679/156/table1Fits to Rothberg & Joseph (RJ04, 2004AJ....128.2098R) merger remnantsNameSource namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Name[078] Source peculiarities (1)meta.codecharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainKMAGAbsolute K band magnitudemagphys.magAbs;em.IR.KfloatnsfitOuter Sersic index of two-component best-fit profilestat.fit.paramfloatnssimOuter Sersic index fit in the same manner to the best-fit simulations (2)stat.fit.paramfloate_nssimRange in nssimstat.errorfloatnsRJ04Sersic index fit to the entire profile (3)stat.fit.paramfloatfeFraction of light in "extra light" component of fitstatfloatfsbFraction of light from stars produced in central, merger-induced starburst (4)statfloate_fsbApproximate interquartile range in fsbstat.errorfloatfgasInitial gas fraction in the best-fitting simulation (5)stat.fit.paramfloate_fgasApproximate interquartile range in fgasstat.errorfloatDmufitVariance about the fitstat.variancefloatDmusimVariance about the simulationstat.variancefloatSimbadSimbad column added by the CDScharNEDSimbad column added by the CDSchar