J/ApJ/898/56ivo://CDS.VizieR/J/ApJ/898/56doi:10.26093/cds/vizier.18980056CDSMiller A.A.Magee M.R.Polin A.Maguire K.Zimmerman E.Yao Y.,Sollerman J.Schulze S.Perley D.A.Kromer M.Dhawan S.Bulla M.,Andreoni I.Bellm E.C.De K.Dekany R.Delacroix A.Fremling C.,Gal-Yam A.Goldstein D.A.Golkhou V.Z.Goobar A.Graham M.J.Irani I.,Kasliwal M.M.Kaye S.Kim Y.-L.Laher R.R.Mahabal A.A.Masci F.J.,Nugent P.E.Ofek E.Phinney E.S.Prentice S.J.Riddle R.Rigault M.,Rusholme B.Schweyer T.Shupe D.L.Soumagnac M.T.Terreran G.,Walters R.Yan L.Zolkower J.Kulkarni S.R.2022-03-16T12:53:53Z2021-12-13T08:47:43ZCDS support team

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

cds-question@unistra.frsupernovaeinfrared-photometryvisible-astronomybroad-band-photometrysurveysultraviolet-photometryspectroscopyEarly observations of Type Ia supernovae (SNe Ia) provide essential clues for understanding the progenitor system that gave rise to the terminal thermonuclear explosion. We present exquisite observations of SN 2019yvq, the second observed SN Ia, after iPTF 14atg, to display an early flash of emission in the ultraviolet (UV) and optical. Our analysis finds that SN 2019yvq was unusual, even when ignoring the initial flash, in that it was moderately underluminous for an SN Ia (M_g_~-18.5mag at peak) yet featured very high absorption velocities (v~15000km/s for SiII{lambda}6355 at peak). We find that many of the observational features of SN 2019yvq, aside from the flash, can be explained if the explosive yield of radioactive 56Ni is relatively low (we measure M_56Ni_=0.31+/-0.05M_{sun}_) and it and other iron-group elements are concentrated in the innermost layers of the ejecta. To explain both the UV/optical flash and peak properties of SN 2019yvq we consider four different models: interaction between the SN ejecta and a nondegenerate companion, extended clumps of ^56^Ni in the outer ejecta, a double-detonation explosion, and the violent merger of two white dwarfs. Each of these models has shortcomings when compared to the observations; it is clear additional tuning is required to better match SN 2019yvq. In closing, we predict that the nebular spectra of SN 2019yvq will feature either H or He emission, if the ejecta collided with a companion, strong [CaII] emission, if it was a double detonation, or narrow [OI] emission, if it was due to a violent merger.2020ApJ...898...56Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/898/56CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/MNRAS/377/1531 : Optical & IR photometry of SN 2004eo (Pastorello+, 2007)J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)J/AJ/139/120 : Low-redshift Type-Ia supernovae (Folatelli+, 2010)J/MNRAS/410/585 : SN 2009dc BVRI light curves (Silverman+, 2011)J/AJ/142/156 : The CSP (DR2): photometry of SNe Ia (Stritzinger+, 2011)J/AJ/143/126 : Spectroscopy of 462 nearby Type Ia SNe (Blondin+, 2012)J/ApJ/749/18 : Swift/UVOT observations of 12 nearby SN-Ia (Brown+, 2012)J/A+A/554/A27 : 2011fe spectrophotometric time series (Pereira+, 2013)J/AJ/146/86 : Cosmicflows-2 catalog (Tully+, 2013)J/MNRAS/444/3258 : Velocities and EW of PTF SNe Ia (Maguire+, 2014)J/ApJ/836/232 : Swift-UVOT obs. analysis of 29 SNe Ia (Brown+, 2017)J/MNRAS/464/2672 : ASAS-SN bright supernova catalog 2013-2014 (Holoien+, 2017)J/AJ/154/211 : The CSP (DR3): photometry of low-z SNeIa (Krisciunas+, 2017)J/ApJ/877/152 : UV to NIR light curves of type Ia SN 2017erp (Brown+, 2019)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/895/32 : Zwicky Transient Facility BTS. I. (Fremling+, 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/898/56https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/898/56http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/898/56https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/898/56https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/898/56http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/898/56GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapUVOpticalInfrareddefaultJ/ApJ/898/56/table1ZTF P48 photometry of SN 2019yvqrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJD[58846.4/58999.3] Epoch, Modified Julian Date (JD-2400000.5)dtime.epochdoubleFlux[66.5/5348.1] Flux in FiltuJyphot.flux.densityfloate_Flux[2.68/91.89] Uncertainty in FluxuJystat.error;phot.fluxfloatFiltFilter (gztf, iztf or rztf) (1)meta.id;instr.filtercharJ/ApJ/898/56/table2UVOT photometry of SN 2019yvqrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJD[58846.8/58907] Epoch, Modified Julian Date (JD-2400000.5)dtime.epochdoubleFlux[4.04/457.9] Flux in FiltuJyphot.flux;em.UVfloate_Flux[2.9/30.8] Uncertainty in FluxuJystat.error;phot.fluxfloatFiltFilter (uvm2, uvw1 or uvw2) (1)meta.id;instr.filtercharJ/ApJ/898/56/table3Spectroscopic observations of SN 2019yvqrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsObserving date (ISO 8601); column added by CDSstime.epochnullableMJD[58848.2/58930.5] Modified Julian Datedtime.epochdoublePhase[-14.9/66.5] Phase relative to T_B,max_ in the SN rest frame (1)dtime.intervalfloatTelTelescope/Instrumentmeta.notecharR[100/4000] Resolution {Delta}{lambda}/{lambda} for the central region of the spectrumspect.resolutionintRangeWavelength range in {AA} units0.1nmmeta.unit;em.wlcharAirMass[1.19/1.88] Airmassobs.airMassfloatFileNameName of the spectrum file; column added by CDSmeta.id;meta.filecharspInteractive plot of the spectrummeta.ref.urlchar