10–13 Aug 2011
AlbaNova University Center
Europe/Stockholm timezone

Lines and Loops: Polarized Spectra Reveal Three-Dimensional Supernova Structure

10 Aug 2011, 19:25
5m
Oskar Klein (AlbaNova University Center)

Oskar Klein

AlbaNova University Center

Speaker

Dr Jennifer Hoffman (University of Denver)

Description

Supernovae of all types are known to be polarized, and many display complex line polarization effects that evolve over time as the supernova evolves. Such behavior reveals details of the clumpy nature of the ejecta, as well as illuminating the characteristics of the circumstellar material lost by the star in its pre-supernova evolution. With the aid of diagnostic tools developed through numerical modeling, polarized supernova spectra have the potential to reveal otherwise inaccessible information about ejecta and surrounding environments. To illustrate this process, I will present results from a grid of simulated polarized line profiles of core-collapse SNe with circumstellar material, created using a three-dimensional spectropolarimetric radiative transfer code. Taking into account spectropolarimetric line effects helps break the degeneracy between line synthesis models and quantify the asphericities often invoked to explain asymmetric line profiles in total light spectra. In addition, three-dimensional modeling can help interpret the mysterious “q-u loop” phenomenon seen in the polarized line profiles of a variety of recent SNe. I will show simultaneous fits to observed line profiles in total and polarized light, investigate the conditions under which q-u loops arise in these models, and discuss the implications of these simulations for interpretation of the polarized spectra of future supernovae.

Primary author

Dr Jennifer Hoffman (University of Denver)

Presentation materials