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Accepted author manuscript
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Photometric and Spectroscopic Properties of Type Ia Supernova 2018oh with Early Excess Emission from the $Kepler$ 2 Observations
AU - Li, W.
AU - Wang, X.
AU - Vinkó, J.
AU - Mo, J.
AU - Hosseinzadeh, G.
AU - Sand, D. J.
AU - Zhang, J.
AU - Lin, H.
AU - Zhang, T.
AU - Wang, L.
AU - Zhang, J.
AU - Chen, Z.
AU - Xiang, D.
AU - Rui, L.
AU - Huang, F.
AU - Li, X.
AU - Zhang, X.
AU - Li, L.
AU - Baron, E.
AU - Derkacy, J. M.
AU - Zhao, X.
AU - Sai, H.
AU - Zhang, K.
AU - Wang, L.
AU - Howell, D. A.
AU - McCully, C.
AU - Arcavi, I.
AU - Valenti, S.
AU - Hiramatsu, D.
AU - Burke, J.
AU - Rest, A.
AU - Garnavich, P.
AU - Tucker, B. E.
AU - Narayan, G.
AU - Shaya, E.
AU - Margheim, S.
AU - Zenteno, A.
AU - Villar, A.
AU - Dimitriadis, G.
AU - Foley, R. J.
AU - Pan, Y.-C.
AU - Coulter, D. A.
AU - Fox, O. D.
AU - Jha, S. W.
AU - Jones, D. O.
AU - Kasen, D. N.
AU - Kilpatrick, C. D.
AU - Piro, A. L.
AU - Riess, A. G.
AU - Rojas-Bravo, C.
AU - Shappee, B. J.
AU - Holoien, T. W.-S.
AU - Stanek, K. Z.
AU - Drout, M. R.
AU - Auchettl, K.
AU - Kochanek, C. S.
AU - Brown, J. S.
AU - Bose, S.
AU - Bersier, D.
AU - Brimacombe, J.
AU - Chen, P.
AU - Dong, S.
AU - Holmbo, S.
AU - Muñoz, J. A.
AU - Mutel, R. L.
AU - Post, R. S.
AU - Prieto, J. L.
AU - Shields, J.
AU - Tallon, D.
AU - Thompson, T. A.
AU - Vallely, P. J.
AU - Villanueva, S., Jr.
AU - Smartt, S. J.
AU - Smith, K. W.
AU - Chambers, K. C.
AU - Flewelling, H. A.
AU - Huber, M. E.
AU - Magnier, E. A.
AU - Waters, C. Z.
AU - Schultz, A. S. B.
AU - Bulger, J.
AU - Lowe, T. B.
AU - Willman, M.
AU - Sárneczky, K.
AU - Pál, A.
AU - Wheeler, J. C.
AU - Bódi, A.
AU - Bognár, Zs.
AU - Csák, B.
AU - Cseh, B.
AU - Csörnyei, G.
AU - Hanyecz, O.
AU - Ignácz, B.
AU - Kalup, Cs.
AU - Könyves-Tóth, R.
AU - Kriskovics, L.
AU - Ordasi, A.
AU - Rajmon, I.
AU - Sódor, A.
AU - Szabó, R.
AU - Szakáts, R.
AU - Zsidi, G.
AU - Milne, P.
AU - Andrews, J. E.
AU - Smith, N.
AU - Bilinski, C.
AU - Brown, P. J.
AU - Nordin, J.
AU - Williams, S. C.
AU - Galbany, L.
AU - Palmerio, J.
AU - Hook, I. M.
AU - Inserra, C.
AU - Maguire, K.
AU - Cartier, Régis
AU - Razza, A.
AU - Gutiérrez, C. P.
AU - Hermes, J. J.
AU - Reding, J. S.
AU - Kaiser, B. C.
AU - Tonry, J. L.
AU - Heinze, A. N.
AU - Denneau, L.
AU - Weiland, H.
AU - Stalder, B.
AU - Barentsen, G.
AU - Dotson, J.
AU - Barclay, T.
AU - Gully-Santiago, M.
AU - Hedges, C.
AU - Cody, A. M.
AU - Howell, S.
AU - Coughlin, J.
AU - Van Cleve, J. E.
AU - Cardoso, J. Vinícius de Miranda
AU - Larson, K. A.
AU - McCalmont-Everton, K. M.
AU - Peterson, C. A.
AU - Ross, S. E.
AU - Reedy, L. H.
AU - Osborne, D.
AU - McGinn, C.
AU - Kohnert, L.
AU - Migliorini, L.
AU - Wheaton, A.
AU - Spencer, B.
AU - Labonde, C.
AU - Castillo, G.
AU - Beerman, G.
AU - Steward, K.
AU - Hanley, M.
AU - Larsen, R.
AU - Gangopadhyay, R.
AU - Kloetzel, R.
AU - Weschler, T.
AU - Nystrom, V.
AU - Moffatt, J.
AU - Redick, M.
AU - Griest, K.
AU - Packard, M.
AU - Muszynski, M.
AU - Kampmeier, J.
AU - Bjella, R.
AU - Flynn, S.
AU - Elsaesser, B.
PY - 2019/1
Y1 - 2019/1
N2 - Supernova (SN) 2018oh (ASASSN-18bt) is the first spectroscopically-confirmed type Ia supernova (SN Ia) observed in the $Kepler$ field. The $Kepler$ data revealed an excess emission in its early light curve, allowing to place interesting constraints on its progenitor system (Dimitriadis et al. 2018, Shappee et al. 2018b). Here, we present extensive optical, ultraviolet, and near-infrared photometry, as well as dense sampling of optical spectra, for this object. SN 2018oh is relatively normal in its photometric evolution, with a rise time of 18.3$\pm$0.3 days and $\Delta$m$_{15}(B)=0.96\pm$0.03 mag, but it seems to have bluer $B - V$ colors. We construct the "uvoir" bolometric light curve having peak luminosity as 1.49$\times$10$^{43}$erg s$^{-1}$, from which we derive a nickel mass as 0.55$\pm$0.04M$_{\odot}$ by fitting radiation diffusion models powered by centrally located $^{56}$Ni. Note that the moment when nickel-powered luminosity starts to emerge is +3.85 days after the first light in the Kepler data, suggesting other origins of the early-time emission, e.g., mixing of $^{56}$Ni to outer layers of the ejecta or interaction between the ejecta and nearby circumstellar material or a non-degenerate companion star. The spectral evolution of SN 2018oh is similar to that of a normal SN Ia, but is characterized by prominent and persistent carbon absorption features. The C II features can be detected from the early phases to about 3 weeks after the maximum light, representing the latest detection of carbon ever recorded in a SN Ia. This indicates that a considerable amount of unburned carbon exists in the ejecta of SN 2018oh and may mix into deeper layers.
AB - Supernova (SN) 2018oh (ASASSN-18bt) is the first spectroscopically-confirmed type Ia supernova (SN Ia) observed in the $Kepler$ field. The $Kepler$ data revealed an excess emission in its early light curve, allowing to place interesting constraints on its progenitor system (Dimitriadis et al. 2018, Shappee et al. 2018b). Here, we present extensive optical, ultraviolet, and near-infrared photometry, as well as dense sampling of optical spectra, for this object. SN 2018oh is relatively normal in its photometric evolution, with a rise time of 18.3$\pm$0.3 days and $\Delta$m$_{15}(B)=0.96\pm$0.03 mag, but it seems to have bluer $B - V$ colors. We construct the "uvoir" bolometric light curve having peak luminosity as 1.49$\times$10$^{43}$erg s$^{-1}$, from which we derive a nickel mass as 0.55$\pm$0.04M$_{\odot}$ by fitting radiation diffusion models powered by centrally located $^{56}$Ni. Note that the moment when nickel-powered luminosity starts to emerge is +3.85 days after the first light in the Kepler data, suggesting other origins of the early-time emission, e.g., mixing of $^{56}$Ni to outer layers of the ejecta or interaction between the ejecta and nearby circumstellar material or a non-degenerate companion star. The spectral evolution of SN 2018oh is similar to that of a normal SN Ia, but is characterized by prominent and persistent carbon absorption features. The C II features can be detected from the early phases to about 3 weeks after the maximum light, representing the latest detection of carbon ever recorded in a SN Ia. This indicates that a considerable amount of unburned carbon exists in the ejecta of SN 2018oh and may mix into deeper layers.
KW - Astrophysics - Solar and Stellar Astrophysics
KW - Astrophysics - High Energy Astrophysical Phenomena
U2 - 10.3847/1538-4357/aaec74
DO - 10.3847/1538-4357/aaec74
M3 - Journal article
VL - 870
JO - The Astrophysical Journal
JF - The Astrophysical Journal
SN - 0004-637X
IS - 1
M1 - 12
ER -