J/ApJ/877/152ivo://CDS.VizieR/J/ApJ/877/152doi:10.26093/cds/vizier.18770152CDSBrown P.J.Hosseinzadeh G.Jha S.W.Sand D.Vieira E.Wang X.Dai M.,Dettman K.G.Mould J.Uddin S.Wang L.Arcavi I.Bento J.Burns C.R.,Diamond T.Hiramatsu D.Howell D.A.Hsiao E.Y.Marion G.H.Mccully C.,Milne P.A.Mirzaqulov D.Ruiter A.J.Valenti S.Xiang D.2021-03-29T09:08:16Z2020-12-18T08:07:59ZCDS support team

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

cds-question@unistra.frsupernovaeultraviolet-photometryinfrared-photometryvisible-astronomybroad-band-photometryWe present space-based ultraviolet/optical photometry and spectroscopy with the Swift Ultra-Violet/Optical Telescope and Hubble Space Telescope (HST), respectively, along with ground-based optical photometry and spectroscopy and near-infrared spectroscopy of supernova SN 2017erp. The optical light curves and spectra are consistent with a normal SN Ia. Compared to previous photometric samples in the near-ultraviolet (NUV), SN 2017erp has UV colors that are redder than NUV-blue SNe Ia corrected to similar optical colors. The chromatic difference between SNe 2011fe and 2017erp is dominated by the intrinsic differences in the UV rather than the expected dust reddening. This chromatic difference is similar to the SALT2 color law, derived from rest-frame ultraviolet photometry of higher redshift SNe Ia. Differentiating between intrinsic UV diversity and dust reddening can have important consequences for determining cosmological distances with rest-frame ultraviolet photometry. This ultraviolet spectroscopic series is the first from HST of a normal, albeit reddened, NUV-red SN Ia and is important for analyzing SNe Ia with intrinsically redder NUV colors. We show model comparisons suggesting that metallicity could be the physical difference between NUV-blue and NUV-red SNe Ia, with emission peaks from reverse fluorescence near 3000{AA} implying a factor of ~10 higher metallicity in the upper layers of SN 2017erp compared to SN 2011fe. Metallicity estimates are very model dependent, however, and there are multiple effects in the UV. Further models and UV spectra of SNe Ia are needed to explore the diversity of SNe Ia, which show seemingly independent differences in the near-UV peaks and mid-UV flux levels.2019ApJ...877..152Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/877/152CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/hst : HST Archived Exposures Catalog (STScI, 2007)J/ApJ/607/665 : Type Ia supernovae at z>1 discovered by HST (Riess+, 2004)J/A+A/430/373 : HI lines in 586 galaxies (Theureau+, 2005)J/ApJ/659/122 : Improved distances to type Ia supernovae (Jha+, 2007)J/MNRAS/376/1301 : UBVRI light-curves of SN 2005cf (Pastorello+, 2007)J/A+A/471/527 : Spectroscopy of SN 2005cf (Garavini+, 2007)J/ApJ/699/L139 : Spectral parameters of SNe Ia (Wang+, 2009)J/ApJS/185/32 : First-year SDSS-II SN results (Kessler+, 2009)J/ApJ/721/1608 : Absolute UV magnitudes of type Ia SNe (Brown+, 2010)J/A+A/523/A7 : Light curves of type Ia supernovae in SNLS (Guy+, 2010)J/MNRAS/425/1819 : Berkeley supernova Ia program. II. (Silverman+, 2012)J/A+A/554/A27 : 2011fe spectrophotometric time series (Pereira+, 2013)J/ApJ/787/29 : UVOT photom. of Super-Chandrasekhar mass SNe Ia (Brown+, 2014)J/ApJ/788/L21 : Measured photometry of SN 2014J from HST (Amanullah+, 2014)J/A+A/568/A22 : Joint analysis of the SDSS-II and SNLS SNe Ia (Betoule+, 2014)J/ApJ/796/L18 : Type Ia supernova 2011de UVOT photometry (Brown, 2014)J/A+A/578/A9 : Optical and NIR spectra of SN iPTF13ebh (Hsiao+, 2015)J/MNRAS/452/4307 : From opt. to IR photometry of SN 2013dy (Pan+, 2015)J/ApJ/826/56 : HST/WFC3 obs. of Cepheids in SN Ia host gal. (Riess+, 2016)J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)J/ApJ/836/232 : Swift-UVOT obs. analysis of 29 SNe Ia (Brown+, 2017)J/MNRAS/499/1424 : Properties of 407 SNe and their 394 hosts (Hakobyan+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/877/152https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/877/152http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/877/152https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/877/152https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/877/152http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/877/152GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapUVOpticalInfrareddefaultJ/ApJ/877/152/table1Photometric magnitudes of SN 2017erpFiltFilter usedinstr.setup;instr.filtercharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMJD[57918.2/58022.4] Modified Julian Datedtime.epochdoublel_magLimit flag on magmeta.code.errorcharmag[13.4/20.1] Apparent magnitude in Filtmagphot.magfloate_mag[0/0.32]? Uncertainty in magmagstat.error;phot.magfloatnullableObsObservatory code (1)meta.code;instr.obstychar