Explosive deaths of stars: Core-collapse supernovae and stellar mergers

Interest in the transient astronomical sky has increased tremendously
thanks to modern time-domain surveys, which have discovered unexpected
diversity in previously known phenomena and identified many new
classes of transients. I will focus on two types of transients that
are important for the nucleosynthesis in the Universe and the
evolution of gravitational wave sources. I will argue that the deaths
of massive stars and the associated core-collapse supernovae are
highly sensitive to initial conditions, which leads to a complex
pattern of neutron star and black hole formation. Many stars are
members of binary systems and their evolution can be significantly
affected by a catastrophic interaction, which results in the rapid
loss of mass, energy and angular momentum, and sometimes even merger
of the binary star. This phase was recently connected to a newly
identified group of red transients and I will present surprising
findings from the theoretical interpretation of observations of these
red transients.

20 Feb 2018
215 Sharp Lab
Ondrej Pejcha, Charles University, Czech Republic