Speaker
Mr
Anders Jerkstrand
(Stockholm University)
Description
Core-collapse SNe offer unique opportunities to look inside massive stars. By
calculating the deposition and degradation of gamma-rays and positrons, solving the
equations for statistical and thermal equilibrium, and considering the effects of multi-
line radiative transfer, we produce model spectra that can be compared with
observations. We apply our model to interpret the spectrum of SN 1987A at an age
of 8 and 19 years, finding a powering of ~1.5E-4 Msun of 44Ti in the iron/silicon core
to satisfactorily reproduce most of the observed lines. We compare models with local
and non-local positron deposition, and find better agreement assuming local trapping.
The cold and neutral ejecta produce strong Fe I lines. We also see that radiative
transfer effects still play a crucial role for the spectral formation even many years
after explosion. One outstanding problem is, however, to explain the weak Fe II 26
mu line observed by Spitzer. I also briefly discuss current work on modeling other
Type IIP SNe in the 200-600 day range.
Primary author
Mr
Anders Jerkstrand
(Stockholm University)
Co-authors
Cecilia Kozma
(Stockholm University)
Claes Fransson
(Stockholm University)
