J/ApJ/927/180ivo://CDS.VizieR/J/ApJ/927/180doi:10.26093/cds/vizier.19270180CDSPerley D.A.Sollerman J.Schulze S.Yao Y.Fremling C.Gal-Yam A.,Ho A.Y.Q.Yang YiKool E.C.Irani I.Yan L.Andreoni I.Baade D.,Bellm E.C.Brink T.G.Chen T.-W.Cikota A.Coughlin M.W.Dahiwale A.,Dekany R.Duev D.A.Filippenko A.V.Hoeflich P.Kasliwal M.M.,Kulkarni S.R.Lunnan R.Masci F.J.Maund J.R.Medford M.S.Riddle R.,Rosnet P.Shupe D.L.Strotjohann N.L.Tzanidakis A.Zheng W.2024-11-06T20:23:52Z2024-02-27T08:41:27ZCDS support team

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

cds-question@unistra.frsupernovaeinfrared-photometryvisible-astronomybroad-band-photometryultraviolet-astronomyspectroscopyWe present observations of SN 2021csp, the second example of a newly identified type of supernova (SN) hallmarked by strong, narrow, P Cygni carbon features at early times (Type Icn). The SN appears as a fast and luminous blue transient at early times, reaching a peak absolute magnitude of -20 within 3 days due to strong interaction between fast SN ejecta (v~30000km/s) and a massive, dense, fast-moving C/O wind shed by the WC-like progenitor months before explosion. The narrow-line features disappear from the spectrum 10-20 days after explosion and are replaced by a blue continuum dominated by broad Fe features, reminiscent of Type Ibn and IIn supernovae and indicative of weaker interaction with more extended H/He-poor material. The transient then abruptly fades ~60days post-explosion when interaction ceases. Deep limits at later phases suggest minimal heavy-element nucleosynthesis, a low ejecta mass, or both, and imply an origin distinct from that of classical Type Ic SNe. We place SN 2021csp in context with other fast-evolving interacting transients, and discuss various progenitor scenarios: an ultrastripped progenitor star, a pulsational pair-instability eruption, or a jet-driven fallback SN from a Wolf-Rayet (W-R) star. The fallback scenario would naturally explain the similarity between these events and radio-loud fast transients, and suggests a picture in which most stars massive enough to undergo a W-R phase collapse directly to black holes at the end of their lives.2022ApJ...927..180Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/927/180CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)J/ApJ/702/226 : Swift/UVOT panchromatic obs. of SN 2008D (Modjaz+, 2009)J/AJ/141/163 : Ultimate LC of SN 1998bw/GRB 980425 (Clocchiatti+, 2011)J/MNRAS/417/916 : Supernovae in the Subaru Deep Field (Graur+, 2011)J/other/Sci/337.444 : RV curves of Galactic massive O stars (Sana+, 2012)J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)J/MNRAS/436/774 : Core collapse supernovae (type Ibc) (Eldridge+, 2013)J/A+A/559/A114 : Updated O3N2 and N2 abundance indicators (Marino+, 2013)J/ApJ/782/42 : Panchromatic observations of PTF11qcj (Corsi+, 2014)J/ApJ/794/23 : Pan-STARRS1 transients optical photometry (Drout+, 2014)J/A+A/565/A27 : Wolf-Rayet stars in Large Magellanic Cloud (Hainich+, 2014)J/ApJ/792/30 : NEOWISE magnitudes for near-Earth objects (Mainzer+, 2014)J/MNRAS/449/1921 : UV/opt/NIR photometry for Type Ibn SNe (Pastorello+, 2015)J/MNRAS/453/3649 : Photometric data for ASASSN-15ed (Pastorello+, 2015)J/ApJ/819/35 : LCs of four transients from PTF & SNLS (Arcavi+, 2016)J/A+A/593/A68 : PTF12os and iPTF13bvn sp. and light curves (Fremling+, 2016)J/A+A/594/A116 : HI4PI spectra and column density maps (HI4PI team+, 2016)J/ApJ/851/107 : iPTF 16asu photometry follow-up (Whitesides+, 2017)J/other/Sci/362.201 : iPTF 14gqr (SN 2014ft) photometry (De+, 2018)J/MNRAS/481/894 : Rapidly evolving transients in the DES (Pursiainen+, 2018)J/ApJ/887/169 : UV-Opt light curves of the type Ic SN 2018gep (Ho+, 2019)J/ApJ/895/L23 : Radio obs. of the transient CSS161010 (Coppejans+, 2020)J/ApJ/905/58 : The local universe with ZTF. I. Ca-rich gaps (De+, 2020)J/ApJ/895/32 : Zwicky Transient Facility BTS. I. (Fremling+, 2020)J/ApJ/902/86 : Type Ic SN 2020bvc UV to NIR LCs and opt. sp. (Ho+, 2020)J/ApJ/895/49 : Opt. spectrum of ZTF18abvkwla & its host galaxy (Ho+, 2020)J/ApJ/903/132 : Radio & optical observations of SN2020oi (Horesh+, 2020)J/ApJ/902/46 : LCO network light curves of SN Ia 2018gv (Yang+, 2020)J/ApJ/900/46 : UV, opt. & IR LC of supernova SN2019dge (Yao+, 2020)J/A+A/651/A81 : SNe Ic from (i)PTF light curves (Barbarino+, 2021)J/ApJ/912/46 : ZTF Type II supernovae with follow-up obs. (Bruch+, 2021)J/ApJ/915/121 : Type Ic SN2018gep phot. & sp. follow-up (Pritchard+, 2021)J/ApJS/255/29 : PTF core-collapse SN host-galaxy sample. I. (Schulze+, 2021)J/ApJ/907/99 : Pre-explosion LC of 227 Supernovae (Strotjohann+, 2021)J/ApJ/924/55 : UV and optical obs. of type Ic SN 2020oi (Gagliano+, 2022)J/other/Nat/601.201 : Photometry of SN 2019hgp (Gal-Yam+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/927/180https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/927/180http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/927/180https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/927/180https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/927/180http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/927/180GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapUVOpticalInfrareddefaultJ/ApJ/927/180/table1Photometry of SN 2021csprecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTelTelescope (1)meta.id;instr.telcharMJD[59250.4/59341.1] Modified Julian Date of Observation (JD-2400000.5)dtime.epochdoubleFiltFilter (ugriz and UVW2, UVM2, UVW1)meta.id;instr.filtercharl_omagLimit flag on omagmeta.code.error;phot.magcharomag[17.27/24.8] Observed AB magnitude in Filt, not corrected for Galactic extinctionmagphot.magfloate_omag[0.02/1.3]? Uncertainty in omagmagstat.error;phot.magfloatnullableJ/ApJ/927/180/table2Log of spectroscopic observations of SN 2021csprecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsUT date of observationstime.epoch;obsnullableMJD[59257.1/59350.4] Modified Julian Datedtime.epochdoublePhase[2.47/88.41] Phasedtime.phasefloatInstFacility/Instrumentmeta.id;instrcharExpExposure time(s)stime.duration;obs.exposurecharGrismGrism/Gratingmeta.id;instr.filtercharSlit[0.2/3] Slit widtharcsecinstr.setup;spect.line.widthfloatlam1[1230/4400] Wavelength lower range0.1nmem.wl;stat.minintlam2[2050/10340] Wavelength upper range0.1nmem.wl;stat.maxintFileNameName of the ASCII file in the subdirectory "sp"; column added by CDSmeta.id;meta.filecharspInteractive spectrum plotmeta.ref.urlchar