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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - K2 Observations of SN 2018oh Reveal a Two-Component Rising Light Curve for a Type Ia Supernova
AU - Dimitriadis, G.
AU - Foley, R. J.
AU - Rest, A.
AU - Kasen, D.
AU - Piro, A. L.
AU - Polin, A.
AU - Jones, D. O.
AU - Villar, A.
AU - Narayan, G.
AU - Coulter, D. A.
AU - Kilpatrick, C. D.
AU - Pan, Y.-C.
AU - Rojas-Bravo, C.
AU - Fox, O. D.
AU - Jha, S. W.
AU - Nugent, P. E.
AU - Riess, A. G.
AU - Scolnic, D.
AU - Drout, M. R.
AU - Barentsen, G.
AU - Dotson, J.
AU - Gully-Santiago, M.
AU - Hedges, C.
AU - Cody, A. M.
AU - Barclay, T.
AU - Howell, S.
AU - Garnavich, P.
AU - Tucker, B. E.
AU - Shaya, E.
AU - Mushotzky, R.
AU - Olling, R. P.
AU - Margheim, S.
AU - Zenteno, A.
AU - Coughlin, J.
AU - Van Cleve, J. E.
AU - Cardoso, J. Vinicius 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.
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 - Smartt, S. J.
AU - Smith, K. W.
AU - Points, S.
AU - Strampelli, G. M.
AU - Brimacombe, J.
AU - Chen, P.
AU - Munoz, J. A.
AU - Mutel, R. L.
AU - Shields, J.
AU - Vallely, P. J.
AU - Villanueva, S., Jr
AU - Li, W.
AU - Wang, X.
AU - Zhang, J.
AU - Lin, H.
AU - Mo, J.
AU - Zhao, X.
AU - Sai, H.
AU - Zhang, X.
AU - Zhang, K.
AU - Zhang, T.
AU - Wang, L.
AU - Zhang, J.
AU - Baron, E.
AU - DerKacy, J. M.
AU - Li, L.
AU - Chen, Z.
AU - Xiang, D.
AU - Rui, L.
AU - Wang, L.
AU - Huang, F.
AU - Li, X.
AU - Hosseinzadeh, G.
AU - Howell, D. A.
AU - Arcavi, I.
AU - Hiramatsu, D.
AU - Burke, J.
AU - Valenti, S.
AU - Tonry, J. L.
AU - Denneau, L.
AU - Heinze, A. N.
AU - Weiland, H.
AU - Stalder, B.
AU - Vinko, J.
AU - Sarneczky, K.
AU - Pa, A.
AU - Bodi, A.
AU - Bognar, Zs.
AU - Csak, B.
AU - Cseh, B.
AU - Csornyei, G.
AU - Hanyecz, O.
AU - Ignacz, B.
AU - Kalup, Cs.
AU - Konyves-Toth, R.
AU - Kriskovics, L.
AU - Ordasi, A.
AU - Rajmon, I.
AU - Sodor, A.
AU - Szabo, R.
AU - Szakats, R.
AU - Zsidi, G.
AU - Williams, S. C.
AU - Nordin, J.
AU - Cartier, R.
AU - Frohmaier, C.
AU - Galbany, L.
AU - Gutierrez, C. P.
AU - Hook, I.
AU - Inserra, C.
AU - Smith, M.
AU - Sand, D. J.
AU - Andrews, J. E.
AU - Smith, N.
AU - Bilinski, C.
N1 - © Copyright 2019 IOP Publishing
PY - 2019/1/1
Y1 - 2019/1/1
N2 - We present an exquisite, 30-min cadence Kepler (K2) light curve of the Type Ia supernova (SN Ia) 2018oh (ASASSN-18bt), starting weeks before explosion, covering the moment of explosion and the subsequent rise, and continuing past peak brightness. These data are supplemented by multi-color Pan-STARRS1 and CTIO 4-m DECam observations obtained within hours of explosion. The K2 light curve has an unusual two-component shape, where the flux rises with a steep linear gradient for the first few days, followed by a quadratic rise as seen for typical SNe Ia. This "flux excess" relative to canonical SN Ia behavior is confirmed in our $i$-band light curve, and furthermore, SN 2018oh is especially blue during the early epochs. The flux excess peaks 2.14$\pm0.04$ days after explosion, has a FWHM of 3.12$\pm0.04$ days, a blackbody temperature of $T=17,500^{+11,500}_{-9,000}$ K, a peak luminosity of $4.3\pm0.2\times10^{37}\,{\rm erg\,s^{-1}}$, and a total integrated energy of $1.27\pm0.01\times10^{43}\,{\rm erg}$. We compare SN 2018oh to several models that may provide additional heating at early times, including collision with a companion and a shallow concentration of radioactive nickel. While all of these models generally reproduce the early K2 light curve shape, we slightly favor a companion interaction, at a distance of $\sim$$2\times10^{12}\,{\rm cm}$ based on our early color measurements, although the exact distance depends on the uncertain viewing angle. Additional confirmation of a companion interaction in future modeling and observations of SN 2018oh would provide strong support for a single-degenerate progenitor system.
AB - We present an exquisite, 30-min cadence Kepler (K2) light curve of the Type Ia supernova (SN Ia) 2018oh (ASASSN-18bt), starting weeks before explosion, covering the moment of explosion and the subsequent rise, and continuing past peak brightness. These data are supplemented by multi-color Pan-STARRS1 and CTIO 4-m DECam observations obtained within hours of explosion. The K2 light curve has an unusual two-component shape, where the flux rises with a steep linear gradient for the first few days, followed by a quadratic rise as seen for typical SNe Ia. This "flux excess" relative to canonical SN Ia behavior is confirmed in our $i$-band light curve, and furthermore, SN 2018oh is especially blue during the early epochs. The flux excess peaks 2.14$\pm0.04$ days after explosion, has a FWHM of 3.12$\pm0.04$ days, a blackbody temperature of $T=17,500^{+11,500}_{-9,000}$ K, a peak luminosity of $4.3\pm0.2\times10^{37}\,{\rm erg\,s^{-1}}$, and a total integrated energy of $1.27\pm0.01\times10^{43}\,{\rm erg}$. We compare SN 2018oh to several models that may provide additional heating at early times, including collision with a companion and a shallow concentration of radioactive nickel. While all of these models generally reproduce the early K2 light curve shape, we slightly favor a companion interaction, at a distance of $\sim$$2\times10^{12}\,{\rm cm}$ based on our early color measurements, although the exact distance depends on the uncertain viewing angle. Additional confirmation of a companion interaction in future modeling and observations of SN 2018oh would provide strong support for a single-degenerate progenitor system.
KW - Astrophysics - High Energy Astrophysical Phenomena
U2 - 10.3847/2041-8213/aaedb0
DO - 10.3847/2041-8213/aaedb0
M3 - Journal article
VL - 870
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
SN - 2041-8205
M1 - L1
ER -