J/ApJ/934/134ivo://CDS.VizieR/J/ApJ/934/134doi:10.26093/cds/vizier.19340134CDSVasylyev S.S.Filippenko A.V.Vogl C.Brink T.G.Brown P.J.,de Jaeger T.Matheson T.Gal-Yam A.Mazzali P.A.Modjaz M.,Patra K.C.Rowe M.Smith N.Van Dyk S.D.Williamson M.Yang Yi,Zheng W.deGraw A.Fox O.D.Gates E.L.Jennings C.Rich R.M.2024-11-06T20:26:19Z2024-08-16T10:05:24ZCDS support team

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

cds-question@unistra.frsupernovaevisible-astronomyspectroscopyultraviolet-astronomyWe present three epochs of early-time ultraviolet (UV) and optical HST/STIS spectroscopy of the young, nearby Type IIP supernova (SN) 2021yja. We complement the HST data with two earlier epochs of Swift UVOT spectroscopy. The HST and Swift UVOT spectra are consistent with those of other well-studied Type IIP SNe. The UV spectra exhibit rapid cooling at early times, while less dramatic changes are seen in the optical. We also present Lick/KAIT optical photometry up to the late-time tail phase, showing a very long plateau and shallow decline compared with other SNe IIP. Our modeling of the UV spectrum with the TARDIS radiative transfer code produces a good fit for a high-velocity explosion, a low total extinction E(B-V)=0.07mag, and a subsolar metallicity. We do not find a significant contribution to the UV flux from an additional heating source, such as interaction with the circumstellar medium, consistent with the observed flat plateau. Furthermore, the velocity width of the MgII{lambda}2798 line is comparable to that of the hydrogen Balmer lines, suggesting that the UV emission is confined to a region close to the photosphere.2022ApJ...934..134Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/934/134CatalogResearchIsServedByTAP VizieR generic servicerelated-toII/183 : UBVRI Photometric Standards (Landolt 1992)VIII/77 : HI spectral properties of galaxies (Springob+, 2005)J/MNRAS/394/2266 : SN 2005cs one-year photometry (Pastorello+, 2009)J/MNRAS/395/1409 : Type II-P SN progenitor constraints (Smartt+, 2009)J/MNRAS/408/827 : Simulations of supernova explosions (Dessart+, 2010)J/MNRAS/412/1441 : SNe luminosity functions (Li+, 2011)J/MNRAS/425/1789 : Berkeley supernova Ia program. I. (Silverman+, 2012)J/ApJ/750/99 : The Pan-STARRS1 photometric system (Tonry+, 2012)J/MNRAS/433/1871 : UBVRI griz light curves of SN 2012aw (Bose+, 2013)J/MNRAS/442/844 : BVRI light curves of type II-P supernovae (Faran+, 2014)J/MNRAS/438/L101 : First month on SN 2013ej (Valenti+, 2014)J/MNRAS/448/2608 : UV and opt. photometric data for SN 2013by (Valenti+, 2015)J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)J/ApJ/875/136 : BVRI, sp. & IR obs. of type II-P SN2017eaw (Van Dyk+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/934/134https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/934/134http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/934/134https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/934/134https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/934/134http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/934/134GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapUVOpticaldefaultJ/ApJ/934/134/table2Kast spectroscopy of SN 2021yja in the 3632-10754{AA} range and Data behind Figure 3 for HST/STIS observationsSeeing[1.2/3]? Seeingarcsecinstr.obsty.seeingfloatnullableExp[500/1500]? Red channel total exposure time (1)stime.duration;obs.exposureintnullablef_Expd: only one exposure was taken with the red channelmeta.codecharFileName1Name of the ASCII file in subdirectory "sp-hst"meta.id;meta.filecharsp1Interactive HST/STIS spectrum plot (from Figure 3)meta.ref.urlcharFileName2Name of the ASCII file in subdirectory "sp-kast"meta.id;meta.filecharsp2Interactive Kast spectrum plot (from Figure 3)meta.ref.urlcharObsObservermeta.id;obscharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintInstInstrument ("Kast" or "STIS")meta.id;instrcharDateDate of observation (UT)time.epochnullablePhase[4/121] Phase; days after explosion (2021-sep-07)dtime.phaseintAirmass[1.9/3]? Average airmassobs.airMassfloatnullable