J/ApJ/889/154ivo://CDS.VizieR/J/ApJ/889/154doi:10.26093/cds/vizier.18890154CDSWhitmore B.C.Chandar R.Lee J.Ubeda L.Adamo A.Aloisi A.,Calzetti D.Cignoni M.Cook D.Dale D.Elmegreen B.G.Gouliermis D.,Grebel E.K.Grasha K.Johnson K.E.Kim H.Sacchi E.Smith L.J.,Tosi M.Wofford A.2022-11-03T07:03:19Z2021-08-10T09:22:56ZCDS support team

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

cds-question@unistra.frglobular-star-clustershst-photometryvisible-astronomygalaxiesstellar-agesstellar-massesWe present a new catalog and results for the cluster system of the starburst galaxy NGC 4449, based on multiband imaging observations taken as part of the LEGUS and H_{alpha}_-LEGUS surveys. We improve the spectral energy fitting method used to estimate cluster ages, and find that the results, particularly for older clusters, are in better agreement with those from spectroscopy. The inclusion of H{alpha} measurements, the role of stochasticity for low-mass clusters, the assumptions about reddening, and the choices of SSP model and metallicity all have important impacts on the age dating of clusters. A comparison with ages derived from stellar color-magnitude diagrams for partially resolved clusters shows reasonable agreement, but large scatter in some cases. The fraction of light found in clusters relative to the total light (i.e., T_L_) in the U, B, and V filters in 25 different ~kiloparsec-size regions throughout NGC 4449 correlates with both the specific region luminosity, R_L_, and the dominant age of the underlying stellar population in each region. The observed cluster age distribution is found to decline over time as dN/d{tau}{propto}{tau}^{gamma}^, with {gamma}=-0.85+/-0.15, independent of cluster mass, and is consistent with strong, early cluster disruption. The mass functions of the clusters can be described by a power law with dN/dM{propto}M^{beta}^ and {beta}=-1.86+/-0.2, independent of cluster age. The mass and age distributions are quite resilient to differences in age-dating methods. There is tentative evidence for a factor of 2-3 enhancement in both the star and cluster formation rate ~100-300Myr ago, indicating that cluster formation tracks star formation generally. The enhancement is probably associated with an earlier interaction event.2020ApJ...889..154Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/889/154CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/hst : HST Archived Exposures Catalog (STScI, 2007)II/342 : Hubble Source Catalog (V1 and V2) (Whitmore+, 2016)J/AJ/109/960 : Young star clusters in The Antennae (Whitmore+ 1995)J/A+AS/139/393 : Young Massive Star Clusters. II. (Larsen, 1999)J/AJ/123/855 : Magellanic Clouds Photometric Survey: SMC (Zaritsky+, 2002)J/AJ/127/1531 : Star formation history of SMC (Harris+, 2004)J/AJ/138/1243 : The star formation history of the LMC (Harris+, 2009)J/A+A/501/949 : Star cluster properties in five spiral galaxies (Mora+, 2009)J/A+A/517/A50 : Ages & luminosities of young SMC/LMC clusters (Glatt+, 2010)J/MNRAS/405/857 : Star clusters in NGC 3256 (Goddard+, 2010)J/AJ/140/75 : Antennae galaxies (NGC 4038/4039) revisited (Whitmore+, 2010)J/AJ/142/129 : HST photometry of NGC 4449 clusters (Annibali+, 2011)J/ApJ/741/86 : XRBs and star clusters in NGC 4449 (Rangelov+, 2011)J/ApJ/752/95 : PHAT stellar cluster survey. I. Year 1 (Johnson+, 2012)J/ApJ/786/117 : M31 PHAT star clusters ages and masses (Fouesneau+, 2014)J/ApJ/812/147 : Slug analysis of clusters in NGC 628 & 7793 (Krumholz+, 2015)J/ApJ/827/33 : PHAT. XVI. Star cluster masses and ages (Johnson+, 2016)J/ApJ/841/92 : Young massive star clusters in 2 LEGUS galaxies (Ryon+, 2017)J/ApJ/845/56 : Star clusters automatically detected in LMC (Bitsakis+, 2017)J/ApJ/853/104 : Ages of star clusters in SMC (Bitsakis+, 2018)J/ApJS/235/23 : LEGUS galaxies1 observations (Sabbi+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/889/154https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/889/154http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/889/154https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/889/154https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/889/154http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/889/154GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/889/154/table4 (Measured and derived properties of star clusters in NGC 4449)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/889/154/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/889/154/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/889/154/table4?GETtext/xml+votable180.050000true187.0002899244.053039550.0055555555555555566/109112.3657755224268815e-19 7.886974166154988e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/889/154?format=asciiOpticaldefaultJ/ApJ/889/154/table4Measured and derived properties of star clusters in NGC 4449recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/595] Cluster id (1)meta.id;meta.mainintXpixx coordinatepixpos.cartesian.x;instr.detdoubleYpixy coordinatepixpos.cartesian.y;instr.detdoubleRAJ2000[186.9/187.2] Right Ascension (J2000)degpos.eq.ra;meta.mainSimbadSimbad column added by the CDSmeta.ref.urlcharDEJ2000[44/44.2] Declination (J2000)degpos.eq.dec;meta.mainF275Wmag[16/27]? HST/WFC3 F275W magnitude (2)magphot.mag;em.UV.200-300nmfloatnullablee_F275Wmag[0.002/2.4]? HST/WFC3 F275W error (2)magstat.errorfloatnullableF336Wmag[16.4/25.5]? HST/WFC3 F336W magnitude (2)magphot.mag;em.opt.Ufloatnullablee_F336Wmag[0.002/0.3]? HST/WFC3 F336W error (2)magstat.errorfloatnullableF435Wmag[17.4/26.1]? HST/ACS F435W magnitude (2)magphot.mag;em.opt.Bfloatnullablee_F435Wmag[0.002/0.2]? HST/ACS F435W error (2)magstat.errorfloatnullableF555Wmag[17.18/25.2]? HST/ACS F555W magnitude (2)magphot.mag;em.opt.Vfloatnullablee_F555Wmag[0.002/0.2]? HST/ACS F555W error (2)magstat.errorfloatnullableF658Nmag[15.88/27.5]? HST/ACS F658N magnitude (2)magphot.mag;em.opt.Rfloatnullablee_F658Nmag[0.001/10.2]? HST/ACS F658N error (2)magstat.errorfloatnullableF814Wmag[16.3/24.4]? HST/ACS F814W magnitude (2)magphot.mag;em.opt.Ifloatnullablee_F814Wmag[0.002/0.3]? HST/ACS F814W error (2)magstat.errorfloatnullableCI[1.2/2.5] F555W Color Index (3)magphot.colorfloatNf[3/6] Number of filtersmeta.numberintCat[1/3] Cluster category (4)meta.codeintQ[0/2] Quality: 1 = good, 2 = poormeta.code.qualintMorph[0/4] Ha morphology (5)meta.codeintlogAge[6.4/10.3] log Age from Halpha-LEGUS (6)log(yr)time.agefloatMass[162/896006] Mass from Halpha-LEGUS (6)solMassphys.massdoubleE(B-V)[0/0.62] E(B-V) Halpha-LEGUS (6)magphot.color.excessfloatlogAgev1[6/10.2] log Age from LEGUS, version 1 (7)log(yr)time.agefloatMassv1[93.6/6.6e+6] Mass from LEGUS, version 1 (7)solMassphys.massdoubleE(B-V)v1[0/1.1] E(B-V) from LEGUS, version 1 (7)magphot.color.excessfloatAdd[0/1]? Added clusters (8)meta.codeintnullable