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Pan-STARRS1 Discovery of Two Ultraluminous Supernovae at z ≈ 0.9

Chomiuk, L. and Forster, K. and Martin, D. C. and Neill, J. D. (2011) Pan-STARRS1 Discovery of Two Ultraluminous Supernovae at z ≈ 0.9. Astrophysical Journal, 743 (2). Art. No. 114. ISSN 0004-637X.

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We present the discovery of two ultraluminous supernovae (SNe) at z ≈ 0.9 with the Pan-STARRS1 Medium Deep Survey. These SNe, PS1-10ky and PS1-10awh, are among the most luminous SNe ever discovered, comparable to the unusual transients SN 2005ap and SCP 06F6. Like SN 2005ap and SCP 06F6, they show characteristic high luminosities (M_(bol) ≈ –22.5 mag), blue spectra with a few broad absorption lines, and no evidence for H or He. We have constructed a full multi-color light curve sensitive to the peak of the spectral energy distribution in the rest-frame ultraviolet, and we have obtained time series spectroscopy for these SNe. Given the similarities between the SNe, we combine their light curves to estimate a total radiated energy over the course of explosion of (0.9-1.4) × 10^(51) erg. We find photospheric velocities of 12,000-19,000 km s^(–1) with no evidence for deceleration measured across ~3 rest-frame weeks around light curve peak, consistent with the expansion of an optically thick massive shell of material. We show that, consistent with findings for other ultraluminous SNe in this class, radioactive decay is not sufficient to power PS1-10ky, and we discuss two plausible origins for these events: the initial spin-down of a newborn magnetar in a core-collapse SN, or SN shock breakout from the dense circumstellar wind surrounding a Wolf-Rayet star.

Item Type:Article
Related URLs:
URLURL TypeDescription
Chomiuk, L.0000-0002-8400-3705
Forster, K.0000-0001-5800-5531
Martin, D. C.0000-0002-8650-1644
Neill, J. D.0000-0002-0466-1119
Additional Information:© 2011 The American Astronomical Society. Received 2011 July 3; accepted 2011 September 14; published 2011 November 29. We thank S. Balberg, D. Kasen, B. Metzger, R. Quimby, and R. Stoll for helpful insights. Laura Chomiuk is a Jansky Fellow of the National Radio Astronomy Observatory. Ryan J. Foley is supported by a Clay Fellowship. This discovery was enabled using the PS1 System operated by the PS1 Science Consortium (PS1SC) and its member institutions. The PS1 Surveys have been made possible through the combinations of the Institute for Astronomy at the University of Hawaii, The Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg, and the Max Planck Institute for Extraterrestial Physics, Garching, The Johns Hopkins University, the University of Durham, the University of Edinburgh, the Queen’s University of Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Network, and the National Central University of Taiwan. Observations reported here were obtained at the MMT Observatory, a joint facility of the Smithsonian Institution and the University of Arizona. This paper uses data products produced by the OIR Telescope Data Center, supported by the Smithsonian Astrophysical Observatory. The EVLA is run by the National Radio Astronomy Observatory, a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc., Gemini Observatory is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovaciόn Productiva (Argentina). Some of the image processing in this paper was run on the Odyssey cluster supported by the FAS Science Division Research Computing Group at Harvard University. We appreciate the excellent support by the staffs at Gemini, MMT, EVLA, and PS1. We are grateful for access to Gemini under programs GN-2010A-Q-30 and GS-2010B-Q-4 (PI: E. Berger) and GN-2010B-Q-34 (PI: J. Tonry). Partial support for this work was provided by National Science Foundation grants AST-1009749 and AST-0807727. Facilities: PS1(GPC1), MMT (Blue Channel Spectrograph, Hectospec), Gemini:Gillett (GMOS), EVLA, GALEX
Group:Space Radiation Laboratory, Space Astrophysics Laboratory
Funding AgencyGrant Number
Clay FellowshipUNSPECIFIED
Smithsonian Astrophysical ObservatoryUNSPECIFIED
Harvard UniversityUNSPECIFIED
Subject Keywords:circumstellar matter; stars: magnetars; supernovae: general; supernovae: individual (PS1-10ky, PS1-10awh)
Issue or Number:2
Record Number:CaltechAUTHORS:20120201-151340323
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Official Citation: Pan-STARRS1 Discovery of Two Ultraluminous Supernovae at z 0.9 L. Chomiuk et al. 2011 ApJ 743 114
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:29076
Deposited By: Ruth Sustaita
Deposited On:01 Feb 2012 23:51
Last Modified:09 Mar 2020 23:45

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