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Post Info TOPIC: Supernova 2006oz


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RE: Supernova 2006oz
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Title: The peculiar case of the "double-humped" super-luminous supernova SN2006oz
Authors: Rachid Ouyed, Denis Leahy (Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, Canada)

SN2006oz is a super-luminous supernova with a mysterious bright precursor that has resisted explanation in standard models. However, such a precursor has been predicted in the dual-shock quark nova (dsQN) model of super-luminous supernovae -- the precursor is the SN event while the main light curve of the SLSN is powered by the Quark-Nova (QN; explosive transition of the neutron star to a quark star). As the SN is fading, the QN re-energizes the SN ejecta, producing a "double-humped" light curve. In this paper, we show the dsQN model successfully reproduces the observed light curve of SN2006oz.

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Title: SN 2006oz: rise of a super-luminous supernova observed by the SDSS-II SN Survey
Authors: G. Leloudas, E. Chatzopoulos, B. Dilday, J. Gorosabel, J. Vinko, A. Gallazzi, J. C. Wheeler, B. Bassett, J. Fischer, J. A. Frieman, J. P. U. Fynbo, A. Goobar, M. Jelinek, D. Malesani, R. C. Nichol, J. Nordin, L. Ostman, M. Sako, D. P. Schneider, M. Smith, J. Sollerman, M. D. Stritzinger, C. C. Thoene, A. de Ugarte Postigo

We study SN 2006oz, a newly-recognised member of the class of H-poor, super-luminous supernovae. We present multi-colour light curves from the SDSS-II SN Survey, covering the rise time, as well as an optical spectrum showing that the explosion occurred at z~0.376. We fit black body functions to estimate the temperature and radius evolution of the photosphere and use the parameterised code SYNOW to model the spectrum. We construct a bolometric light curve and compare with explosion models. The very early light curves show a dip in the g and r-bands and a possible initial cooling phase in the u-band before rising to maximum light. The bolometric light curve shows a precursor plateau with a duration between 6-10 days in the rest-frame. A lower limit of M_u < -21.5 can be placed on the absolute peak luminosity of the SN, while the rise time is constrained to be at least 29 days. During our observations, the emitting sphere doubled its radius to 2x10^15 cm, while the temperature remained hot at 15000 K. As for other similar SNe, the spectrum is best modelled with elements including O II and Mg II, while we tentatively suggest that Fe III might be present. We suggest that the precursor plateau might be related to a recombination wave in a circumstellar medium (CSM) and discuss whether it is a common property of all similar explosions. The subsequent rise can be equally well described by input from a magnetar or by ejecta-CSM interaction, but the models are not well constrained due to the lack of post-maximum observations, and CSM interaction has difficulties accounting for the precursor plateau self-consistently. Radioactive decay is less likely as a mechanism powering the luminosity. The host galaxy, detected in deep imaging with the 10 m GTC, is a moderately young and star-forming, but not a starburst, galaxy. It has an absolute magnitude of M_g = -16.9.

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