[Okc-wp4] EO meeting on Thursday (15th of March, 13:00)

Francesco Taddia ftadd at astro.su.se
Tue Mar 13 14:56:30 CET 2018


Hi all, 

next meeting on thursday we will have Ragnhild Lunnan speaking about her recent work on a super-luminous supernova.
Please note that the meeting will be in the usual KTH room on the 5th floor with a view, 13:00-14:00.

Here title and abstract:

%%%%%%%%%

Title: A Circumstellar Shell around a Superluminous Supernova Revealed in a Light Echo

Abstract: Superluminous supernovae (SLSNe) are a rare class of transients with peak luminosities 10-100 times those of normal core-collapse and Type Ia SNe, and whose progenitors and energy sources are still debated. Here, I will report on a surprising result from our Keck late-time spectroscopic survey of SLSNe: the discovery of a shell of circumstellar material (CSM) around the supernova, revealed by both absorption and subsequent re-emission in Mg II from the shell, in an “echo” of the SN light. The blueshift of the absorption lines allow us to measure the velocity of the CSM shell, while the time delay between the blueshifted and redshifted emission lines directly constrains the size of the shell. While pre-supernova mass loss is not uncommon in massive stars, this kind of observation is nearly unique, with the closest observed analogue being the ionization of the ring around SN1987A by the supernova flash. I will discuss both the circumstances that allowed us to observe it in this particular instance, and the implications for superluminous supernova progenitors and mass loss mechanisms. In this case, the high shell velocity (~3000 km/s) and implied time of the eruption (~40 years prior to explosion) may point to a pulsational pair-instability origin.
%%%%%%%%%

cheers

/Francesco


-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.su.se/pipermail/okc-wp4-at-fysik.su.se/attachments/20180313/f2d07711/attachment.html>


More information about the Okc-wp4-at-fysik.su.se mailing list