J/ApJ/902/48ivo://CDS.VizieR/J/ApJ/902/48doi:10.26093/cds/vizier.19020048CDSBulla M.Miller A.A.Yao Y.Dessart L.Dhawan S.Papadogiannakis S.,Biswas R.Goobar A.Kulkarni S.R.Nordin J.Nugent P.Polin A.,Sollerman J.Bellm E.C.Coughlin M.W.Dekany R.Golkhou V.Z.,Graham M.J.Kasliwal M.M.Kupfer T.Laher R.R.Masci F.J.Porter M.,Rusholme B.Shupe D.L.2022-05-18T13:52:39Z2022-05-02T13:12:05ZCDS support team

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

cds-question@unistra.frsupernovaesurveysastronomical-modelsColors of Type Ia supernovae (SNe Ia) in the first few days after explosion provide a potential discriminant between different models. In this paper, we present g-r colors of 65 SNe Ia discovered within 5d from first light by the Zwicky Transient Facility in 2018, a sample that is about three times larger than that in the literature. We find that g-r colors are intrinsically rather homogeneous at early phases, with about half of the dispersion attributable to photometric uncertainties ({sigma}_noise_~{sigma}_int_~0.18mag). Colors are nearly constant starting from 6 days after first light (g-r~-0.15mag), while the time evolution at earlier epochs is characterized by a continuous range of slopes, from events rapidly transitioning from redder to bluer colors (slope of ~-0.25mag/day) to events with a flatter evolution. The continuum in the slope distribution is in good agreement both with models requiring some amount of ^56^Ni mixed in the outermost regions of the ejecta and with "double-detonation" models having thin helium layers (M_He_=0.01M_{sun}_) and varying carbon-oxygen core masses. At the same time, six events show evidence for a distinctive "red bump" signature predicted by double-detonation models with larger helium masses. We finally identify a significant correlation between the early-time g-r slopes and supernova brightness, with brighter events associated to flatter color evolution (p-value=0.006). The distribution of slopes, however, is consistent with being drawn from a single population, with no evidence for two components as claimed in the literature based on B-V colors.2020ApJ...902...48Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/902/48CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/578/A9 : Optical and NIR spectra of SN iPTF13ebh (Hsiao+, 2015)J/ApJ/826/144 : Follow-up observations of SNIa ASASSN-14lp (Shappee+, 2016)J/ApJ/869/56 : Updated calibration of the CSP-I SNe Ia sample (Burns+, 2018)J/A+A/614/A71 : SNF20080514-002 and LSQ12fxd spectra (Nordin+, 2018)J/ApJ/870/L1 : K2 obs. of type Ia supernova SN 2018oh (Dimitriadis+, 2019)J/ApJ/870/13 : K2 LC alternative analysis of ASASSN-18bt (Shappee+, 2019)J/ApJ/886/152 : ZTF early observations of Type Ia SNe. I. LCs (Yao+, 2019)J/ApJ/896/165 : Optical light curves of SN 2016hnk (Jacobson-Galan+, 2020)J/ApJ/902/47 : ZTF early obs. of type Ia SNe. II. Rise time (Miller+, 2020)J/A+A/634/A37 : TURTLS Light curves of ^56^Ni distributions (Magee+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/902/48https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/902/48http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/902/48https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/902/48https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/902/48http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/902/48GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/902/48/table1 (Properties of the 65 SNe Ia in our sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/902/48/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/902/48/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/902/48/table1?GETtext/xml+votable180.050000true251.605410125.42148720.0055555555555555566/9052 9067 9178 9212 9239 9386 9470 9520 9540 9564 9608 9639 9678 9706 9759 9793 9811 10000 10004 10044 10074 10112 10120 10159 10187 10200 10637 10674 10717 10728 11109 11186 11199 11204 11297 11333 11385 11548 11584 11614 11619 11685 12124 12776 14874 14896 14973 15007 15018 15050 15070 15270-15271 15299 15338 15349 15932 16060 16079 16102 20223 32486 32520 32614https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/902/48?format=asciidefaultJ/ApJ/902/48/table1Properties of the 65 SNe Ia in our sampleZTFZTF identifiermeta.idcharNameTNS identifiermeta.id;meta.maincharsTypeSN Ia subtype (1)src.classcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_sType[*] *=classification could not be reliably determined from spectroscopy alonemeta.codecharz[0.018/0.15] Spectroscopic redshift from Paper I (Yao+, 2019, J/ApJ/886/152)src.redshiftfloatn_zFlag on z (2)meta.notechart-tfl[0.46/4.96] Rest-frame time of first detection in both g and r relative to first light t_fl_ (T_g-r_^first^-t_fl_)dtime.intervalfloate_t-tfl[0.07/2.87] Lower uncertainty on t-tfldstat.error;phot.colorfloatE_t-tfl[0.07/3.12] Upper uncertainty on t-tfldstat.error;stat.maxfloatdg-r/dt[-0.28/0.23]? g-r linear slope ({Delta}_g-r_/{Delta}t) (3)mag/dstat.fit.paramfloatnullablee_dg-r/dt[0/0.25]? dg-r/dt uncertaintymag/dstat.errorfloatnullablex1[-2.53/4.14] SALT x1 parameter from Paper I (Yao+, 2019, J/ApJ/886/152)stat.fit.paramfloate_x1[0.02/0.66] x1 uncertaintystat.errorfloatE(B-V)[0/0.77] Host reddening inferred using SNooPy (Burns+ 2014ApJ...789...32B)magphot.color.excessfloatKgr[-0.009/0.1] Averaged K-correction (4)magarith.factor;phot.magfloatSimbadSimbad column added by the CDSmeta.ref.urlcharNEDNED column added by the CDSmeta.ref.urlchar_RAPositions from Paper I (Yao+, 2019, J/ApJ/886/152) (right ascension part)degpos.eq.ra;meta.main_DEPositions from Paper I (Yao+, 2019, J/ApJ/886/152) (declination part)degpos.eq.dec;meta.main