J/ApJ/962/17ivo://CDS.VizieR/J/ApJ/962/17CDSWang Q.Rest A.Dimitriadis G.Ridden-Harper R.Siebert M.R.,Magee M.Angus C.R.Auchettl K.Davis K.W.Foley R.J.Fox O.D.,Gomez S.Jencson J.E.Jones D.O.Kilpatrick C.D.Pierel J.D.R.,Piro A.L.Polin A.Politsch C.A.Rojas-Bravo C.Shahbandeh M.,Villar V.A.Zenati Y.Ashall C.Chambers K.C.Coulter D.A.,de Boer T.DiLullo N.Gall C.Gao H.Hsiao E.Y.Huber M.E.Izzo L.,Khetan N.LeBaron N.Magnier E.A.Mandel K.S.McGill P.Miao H.-Y.,Pan Y.-C.Stevens C.P.Swift J.J.Taggart K.Yang G.2026-06-24T09:19:39Z2026-06-24T09:19:39ZCDS support team

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

cds-question@unistra.frsupernovaeinfrared-photometryvisible-astronomybroad-band-photometryspectroscopyWe present high-cadence ultraviolet through near-infrared observations of the Type Ia supernova (SN Ia) 2023bee at D=32+/-3Mpc, finding excess flux in the first days after explosion, particularly in our 10min cadence TESS light curve and Swift UV data. Compared to a few other normal SNe Ia with early excess flux, the excess flux in SN2023bee is redder in the UV and less luminous. We present optical spectra of SN 2023bee, including two spectra during the period where the flux excess is dominant. At this time, the spectra are similar to those of other SNe Ia but with weaker SiII, CII, and CaII absorption lines, perhaps because the excess flux creates a stronger continuum. We compare the data to several theoretical models on the origin of early excess flux in SNe Ia. Interaction with either the companion star or close-in circumstellar material is expected to produce a faster evolution than observed. Radioactive material in the outer layers of the ejecta, either from double detonation explosion or from a ^56^Ni clump near the surface, cannot fully reproduce the evolution either, likely due to the sensitivity of early UV observable to the treatment of the outer part of ejecta in simulation. We conclude that no current model can adequately explain the full set of observations. We find that a relatively large fraction of nearby, bright SNe Ia with high-cadence observations have some amount of excess flux within a few days of explosion. Considering potential asymmetric emission, the physical cause of this excess flux may be ubiquitous in normal SNe Ia.2024ApJ...962...17Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/962/17CatalogResearchIsServedByTAP VizieR generic servicerelated-toIV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)II/389 : The Pan-STARRS release 1 (PS1) Survey - DR2 (Magnier+, 2025)J/AJ/133/403 : Light curve of 11 type Ia supernovae (Garg+, 2007)J/ApJ/700/331 : Light curves of type Ia supernovae (CfA3) (Hicken+, 2009)J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)J/A+A/554/A27 : 2011fe spectrophotometric time series (Pereira+, 2013)J/ApJ/795/44 : PS1 SNe Ia (0.02<z<0.7) griz light curves (Rest+, 2014)J/ApJ/826/144 : Follow-up observations of SNIa ASASSN-14lp (Shappee+, 2016)J/AJ/154/211 : The CSP (DR3): phot. of low-z SNe Ia (Krisciunas+, 2017)J/ApJ/853/62 : Optical & NIR spectra & LCs of SN2016ija (Tartaglia+, 2018)J/ApJ/867/105 : ATLAS all-sky stellar ref. cat., ATLAS-REFCAT2 (Tonry+, 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/902/48 : ZTF early obs. of type Ia supernovae. III. (Bulla+, 2020)J/A+A/634/A37 : TURTLS Light curves of ^56^Ni distributions (Magee+, 2020)J/ApJ/898/56 : UVOT, ZTF gri LCs & sp. of the SN Ia 2019yvq (Miller+, 2020)J/ApJ/902/47 : ZTF early obs. of type Ia SNe. II. Rise time (Miller+, 2020)J/ApJ/908/51 : TESS early LCs of type Ia Supernovae (Fausnaugh+, 2021)J/ApJ/923/L8 : Follow-up phot. & sp. of SNIa 2020hvf (Jiang+, 2021)J/ApJ/914/50 : Opt. phot. and GMOS & NIRES sp. of SN2019yvq (Tucker+, 2021)J/ApJ/923/167 : SN 2018agk spectra and NIR-UV light curves (Wang+, 2021)J/ApJ/927/78 : Phot. & sp. follow-up of SN2020esm (Dimitriadis+, 2022)J/ApJ/933/L45 : LCs and spectra of type Ia SN 2021aefx (Hosseinzadeh+, 2022)J/ApJS/266/9 : Young Supernova Experiment (YSE) DR1 (Aleo+, 2023)J/ApJ/956/108 : TESS 4yrs obs. of Type Ia supernovae (Fausnaugh+, 2023)J/ApJ/946/7 : BVI light curves and sp. of Type Ia SN 2018aoz (Ni+, 2023)J/ApJ/943/L20 : Phot. obs. of SN 2022ilv and SN 2020hvf (Srivastav+, 2023)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/962/17https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/962/17http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/962/17https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/962/17https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/962/17http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/962/17GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/ApJ/962/17/table3Log of spectroscopic observations of SN 2023beerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSpectrum number as in Figure 3meta.idintDateDate of observation (UT)time.epochnullableMJD[59976.76/60064.2] Modified Julian Datedtime.epochdoublePhase[-15.74/71.24] Phase relative to B-band maximum on MJD 59992.58 according to the SALT3 fitdtime.phasefloatTelTelescopemeta.id;instr.telcharInstInstrumentmeta.id;instrcharspInteractive spectrum Plotmeta.ref.urlcharJ/ApJ/962/17/fig2Multi-band light curves of SN 2023beerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJD[58814.6/60065]? Modified Julian Datedtime.epochdoublenullableBandObservation bandinstr.bandpass;obscharmag[-7.37/26.61]? Apparent magnitude in Bandmagphot.magfloatnullablee_mag[-15.55/188.75]? Uncertainty in mag (1)magstat.error;phot.magfloatnullableFlux[-61/3.3e+12]? Flux densityuJyphot.flux.densitydoublenullablee_Flux[0/1.83e+12] Uncertainty in FluxuJystat.error;phot.fluxdoubleZP[23.9] Flux zero-point magnitudemagstat.fit;arith.zpfloatSys[ab] Magnitude system usedmeta.notecharTelTelescope identifier (2)meta.id;instr.telcharJ/ApJ/962/17/fig3Optical spectra series of SN 2023beerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/20] Spectrum identifier (1)meta.idintlambda[0/10896.1] Wavelength; Angstroms0.1nmem.wldoubleFlux[-1.2/35.7] Flux densityuJyphot.fluxdoublee_Flux[0/0.84]? Uncertainty in FluxuJystat.error;phot.fluxdoublenullableJ/ApJ/962/17/fig11The raw TESS light curve of SN 2023beerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJD[59962.29/59981.7]? Modified Julian Datedtime.epochdoublenullableFlux[-24300/38500] Flux densityuJyphot.flux.densitydoublee_Flux[0/3133] Uncertainty in FluxuJystat.error;phot.flux.densitydouble