Thursday, August 4, 2011

Supernovae Galore!

Over the past month SALT has followed up on three different supernovae. The first two were initially discovered by an amateur astronomer here in the Western Cape, Berto Monard. Berto is a well-renowned supernova and GRB hunter and was awarded the Gill Medal by the ASSA in 2004. The first supernova we followed up on was SN 2011eb (PSN J01573658-5748008). It was first discovered by Berto on the night of July 9 and we followed up with spectroscopy the following night. It was identified as a Type Ia supernova within a few days of maximum light. The findings have been publised as CBAT 2764. Images of the SN and it's host galaxy can be found here and here. Below is the SALT spectrum and model used to make the ID.

The next supernova, SN 2011ec, was captured a couple nights later at the very end of the night as twilight was approaching. It was another of Berto's discoveries, but he had done so on 14 May so we were following up about two months or so after maximum light. The ID confirms that it is a Type Ia of that age. While not groundbreaking in and of itself, it does show that SALT is capable of observing late-stage extragalactic supernovae relatively easily. The findings have been published as CBAT 2765 and the spectrum is shown below and an image can be found here.

Thirdly, and most exciting, are the spectroscopy obtained this week of SN 2011ei which appears to be an energetic "hypernova" similar to SN 2003bg. This initial finding has been published as ATel #3526. Shown below is our first spectrum plotted at the top along with other similar objects from the past. We will be following up on this object as much as we can to get better signal-to-noise and to monitor its evolution.

1 comment:

  1. Just love these highly detailed reports and graphs. Keep up the good work and keep them coming.

    Dave O'Hearns