tag:blogger.com,1999:blog-37446792977946129722011-04-22T02:28:29.419ZSupernova Watch will not watch for supernovae. We shall watch for new and interesting papers on supernovae, their mechanisms, their connections with other phenomenon including GRBs, their circumstellar interactions, the supernova remnants that they produce and the pulsars and pulsar wind nebulae that they leave behind. We shall try to give the links to the astro-ph eprint wherever possible.Sayan Chakrabortihttp://www.blogger.com/profile/06876627425675685596noreply@blogger.comBlogger11100tag:blogger.com,1999:blog-3744679297794612972.post-85164352606116801372007-05-10T17:03:00.000Z2007-05-10T17:19:30.033ZE. O. Ofek, P. B. Cameron, M. M. Kasliwal, A. Gal-Yam, A. Rau, S. R. Kulkarni, D. A. Frail, P. Chandra, S. B. Cenko, A. M. Soderberg, S. Immler<br /><br />Abstract: With an extinction-corrected V-band peak absolute magnitude of about -22.2, supernova (SN) 2006gy is probably the brightest SN ever observed. We report on multi-wavelength observations of this SN and its environment. The optical spectra and the slow light-curve evolution resemble those of members of the hybrid IIn/Ia SN class, also called type-IIa SNe. The total radiated energy in the first two months is about 1.2 x 10^51 erg, comparable to the total mechanical energy release of a type-Ia SN. If the engine behind SN2006gy is a type-Ia SN, the rapid conversion of mechanical energy to radiation requires a very dense circumstellar medium, which in turns implies an extreme mass loss rate for the progenitor, ~10^-2 solar mass per year over a period of ~100 yr prior to explosion. Such a mass-loss rate is a challenging requirement for most proposed models of type-IIa SN. Unlike the four previously known type-IIa SNe, the host galaxy NGC 1260 is not a star-forming galaxy, but rather an S0 galaxy dominated by an old stellar population, which probably has a relatively high metallicity. However, our high resolution adaptive optics images reveal a dust lane in this galaxy, passing about 300 pc (projected) from the SN position. These observations add more questions as to the origin of the enigmatic IIa supernovae.<div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/3744679297794612972-8516435260611680137?l=supernovawatch.blogspot.com' alt='' /></div>Sayan Chakrabortihttp://www.blogger.com/profile/06876627425675685596noreply@blogger.com0