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arXiv · 1008.4353

Displaying the Heterogeneity of the SN 2002cx-like Subclass of Type Ia Supernovae with Observations of the Pan-STARRS-1 Discovered SN2009ku

G. Narayan·R. J. Foley·E. Berger·M. T. Botticella·R. Chornock·M. E. Huber·A. Rest·D. Scolnic·S. Smartt·A. M. Soderberg·W. S. Burgett·K. C. Chambers·G. Gates·T. Grav·N. Kaiser·R. P. Kirshner·E. A. Magnier·J . S. Morgan·P. A. Price·A. G. Riess·C. W. Stubbs·W. E. Sweeney·J. L. Tonry·R. J. Wainscoat·W. M. Wood-Vasey
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Abstract

SN2009ku, discovered by Pan-STARRS-1, is a Type Ia supernova (SNIa), and a member of the distinct SN2002cx-like class of SNeIa. Its light curves are similar to the prototypical SN2002cx, but are slightly broader and have a later rise to maximum in g. SN2009ku is brighter (~0.6 mag) than other SN2002cx-like objects, peaking at M_V = -18.4 mag - which is still significantly fainter than typical SNeIa. SN2009ku, which had an ejecta velocity of ~2000 kms^-1 at 18 days after maximum brightness is spectroscopically most similar to SN2008ha, which also had extremely low-velocity ejecta. However, SN2008ha had an exceedingly low luminosity, peaking at M_V = -14.2 mag, ~4 mag fainter than SN2009ku. The contrast of high luminosity and low ejecta velocity for SN2009ku is contrary to an emerging trend seen for the SN2002cx class. SN2009ku is a counter-example of a previously held belief that the class was more homogeneous than typical SNeIa, indicating that the class has a diverse progenitor population and/or complicated explosion physics. As the first example of a member of this class of objects from the new generation of transient surveys, SN2009ku is an indication of the potential for these surveys to find rare and interesting objects.

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G. Narayan, R. J. Foley, E. Berger, M. T. Botticella, R. Chornock, M. E. Huber, A. Rest, D. Scolnic, S. Smartt, A. M. Soderberg, W. S. Burgett, K. C. Chambers, G. Gates, T. Grav, N. Kaiser, R. P. Kirshner, E. A. Magnier, J . S. Morgan, P. A. Price, A. G. Riess, C. W. Stubbs, W. E. Sweeney, J. L. Tonry, R. J. Wainscoat, W. M. Wood-Vasey. 2010-08-25. Displaying the Heterogeneity of the SN 2002cx-like Subclass of Type Ia Supernovae with Observations of the Pan-STARRS-1 Discovered SN2009ku. https://doi.org/10.1088/2041-8205%2F731%2F1%2Fl11

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