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MJ Childress, RA Scalzo, SA Sim, BE Tucker, F Yuan, BP Schmidt, SB Cenko, JM Silverman, C Contreras, EY Hsiao, M Phillips, N Morrell, SW Jha, C McCully, AV Filippenko, JP Anderson, S Benetti, F Bufano, T de Jaeger, F Forster Show all



We present 65 optical spectra of the Type Ia SN 2012fr, 33 of which were obtained before maximum light. At early times, SN 2012fr shows clear evidence of a high-velocity feature (HVF) in the Si II λ6355 line that can be cleanly decoupled from the lower velocity "photospheric" component. This Si II λ6355 HVF fades by phase -5; subsequently, the photospheric component exhibits a very narrow velocity width and remains at a nearly constant velocity of 12,000 km s-1 until at least five weeks after maximum brightness. The Ca II infrared triplet exhibits similar evidence for both a photospheric component at v 12,000 km s-1 with narrow line width and long velocity plateau, as well as an HVF beginnin..

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University of Melbourne Researchers


Awarded by Australian Research Council Centre of Excellence for All-sky Astrophysics (CAAS-TRO)

Awarded by Australian Research Council Future Fellowship

Awarded by CONICYT through FONDECYT grant

Awarded by Millennium Center for Supernova Science

Awarded by FONDECYT

Awarded by NSF

Awarded by Science and Technology Facilities Council

Awarded by Direct For Mathematical & Physical Scien

Awarded by Division Of Astronomical Sciences

Funding Acknowledgements

This research was conducted by the Australian Research Council Centre of Excellence for All-sky Astrophysics (CAAS-TRO), through project number CE110001020. Chris Lidman is the recipient of an Australian Research Council Future Fellowship (program number FT0992259). J.A. acknowledges support by CONICYT through FONDECYT grant 3110142, and by the Millennium Center for Supernova Science (P10-064-F), with input from "Fondo de Innovacion para la Competitividad, del Ministerio de Economia, Fomento y Turismo de Chile." A.G.-Y. is supported by the EU/FP7 via an ERC grant. F.B. acknowledges support from FONDECYT through Postdoctoral grant 3120227. F.B. and G.P. thank the Millennium Center for Supernova Science for grant P10-064-F (funded by "Programa Bicentenario de Ciencia y Tecnologia de CONICYT" and "Programa Iniciativa Cientifica Milenio de MIDEPLAN"). S.B. is partially supported by the PRIN-INAF 2011 with the project "Transient Universe: from ESO Large to PESSTO." Support for this research at Rutgers University was provided in part by NSF CAREER award AST-0847157 to S.W.J. M.D.S. and F.T. acknowledge the generous support provided by the Danish Agency for Science and Technology and Innovation through a Sapere Aude Level 2 grant. E.Y.H. is supported by the NSF under grant AST-1008343. A.V.F.'s group at U.C. Berkeley is supported by Gary and Cynthia Bengier, the Richard and Rhoda Goldman Fund, the Christopher R. Redlich Fund, the TABASGO Foundation, and NSF grant AST-1211916.This work is based in part on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile, as part of PESSTO (the Public ESO Spectroscopic Survey for Transient Objects) ESO programs 188.D-3003 and 089.D-0305. This paper also uses data obtained at the South African Astronomical Observatory (SAAO). Some observations were taken with the Southern African Large Telescope (SALT) as part of proposal ID 2012-1-RU-005 (PI: Jha). Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA; the observatory was made possible by the generous financial support of the W.M. Keck Foundation. Based in part on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. For their excellent assistance, we are grateful to the staffs of the many observatories where we collected data.This research has made prodigious use of the NASA/IPAC Extragalactic Database (NED), which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. It has also made use of NASA's Astrophysics Data System (ADS), the CfA Supernova Archive (funded in part by NSF grant AST-0907903), and the Central Bureau for Astronomical Telegrams (CBAT) list of SNe (