Institute for Advanced Study Informal Astrophysics Seminar - NOTE DAY
The Explosion Mechanism of Core-Collapse Supernovae and its Observational Signatures
Many massive stars explode as core-collapse supernovae. Supernova
simulations show that the shock wave accompanying formation of the
proto-neutron star evolves into a quasi-static accretion shock and it
proves difficult to revive its outward propagation. The stalled
accretion shock turns into explosion when the neutrino luminosity from
the collapsed core exceeds a critical value L_crit (the "neutrino
mechanism"). I will show the connection between the steady-state
isothermal accretion flows with bounding shocks and the neutrino
mechanism: there is a maximum, critical sound speed above which it is
impossible to maintain accretion with a standoff shock. I will derive
the "antesonic" condition, which characterizes the transition to
explosion over a broad range in accretion rate, PNS properties and
microphysics. Additionally, I will characterize the effects of
accretion luminosity and collective neutrino oscillations on L_crit.
The physics of the explosion mechanism and the progenitor structure
are imprinted in the observed distribution of neutron star masses. I
will use Bayesian analysis to model the double neutron star mass
distribution to infer the properties of the progenitor binary
population, fallback during the explosion, and constrain the mass
coordinate where the explosion develops.
Date & Time
November 16, 2012 | 11:00am – 12:00pm
Location
Bloomberg Hall, Astrophysics LibrarySpeakers
Ondrej Pejcha
Affiliation
The Ohio State University