* Astronomy

Title: SN 2009kf : a UV bright type IIP supernova discovered with Pan-STARRS 1 and GALEX
Authors: M.T. Botticella (Queen's University Belfast), C. Trundle, A. Pastorello, S. Rodney, A. Rest, S. Gezari, S. J. Smartt, G. Narayan, M.E. Huber, J. L. Tonry, D. Young, K. Smith, F. Bresolin, S. Valenti, R. Kotak, S. Mattila, E. Kankare, W. M. Wood-Vasey, A. Riess, J. D. Neill, K. Forster, D. C. Martin, C. W. Stubbs, W. S. Burgett, K. C. Chambers, T. Dombeck, H. Flewelling, T. Grav, J. N. Heasley, K. W. Hodapp, N. Kaiser, R. Kudritzki, G. Luppino, R. H. Lupton, E. A. Magnier, D. G. Monet, J. S. Morgan, P. M. Onaka, P. A. Price, P. H. Rhoads, W. A. Siegmund, W. E. Sweeney, R. J. Wainscoat, C. Waters, M. F. Waterson, C.G. Wynn-Williams

We present photometric and spectroscopic observations of a luminous type IIP Supernova 2009kf discovered by the Pan-STARRS 1 (PS1) survey and detected also by GALEX. The SN shows a plateau in its optical and bolometric light curves, lasting approximately 70 days in the rest frame, with absolute magnitude of M_V = -18.4 mag. The P-Cygni profiles of hydrogen indicate expansion velocities of 9000km/s at 61 days after discovery which is extremely high for a type IIP SN. SN 2009kf is also remarkably bright in the near-ultraviolet (NUV) and shows a slow evolution 10-20 days after optical discovery. The NUV and optical luminosity at these epochs can be modelled with a black-body with a hot effective temperature (T ~16,000 K) and a large radius (R ~1x10^{15} cm). The bright bolometric and NUV luminosity, the lightcurve peak and plateau duration, the high velocities and temperatures suggest that 2009kf is a type IIP SN powered by a larger than normal explosion energy. Recently discovered high-z SNe (0.7 < z < 2.3) have been assumed to be IIn SNe, with the bright UV luminosities due to the interaction of SN ejecta with a dense circumstellar medium (CSM). UV bright SNe similar to SN 2009kf could also account for these high-z events, and its absolute magnitude M_NUV = -21.5 ±0.5 mag suggests such SNe could be discovered out to z ~2.5 in the PS1 survey.

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-- Edited by Blobrana on Monday 1st of February 2010 03:13:05 AM