Astroparticle Seminars
Upcoming seminars
23.09.2024. at 14.15h:
Mariam Gogilashvili (Niels Bohr Institute) - Towards Predicting Which Massive Stars Explode
Place: Aud. A, Blegdamsvej 17
Abstract:
At the end of their lives, most massive stars undergo core collapse. Some stars explode as a core-collapse supernova (CCSN) explosion leaving behind neutron stars (NS) while others fail to explode and collapse to stellar-mass black holes (BH). Predicting which massive stars explode, and thus the resulting NS and BH mass distributions, remains a major challenge in CCSN theory. We develop an analytic force explosion condition (FEC) to predict which massive stars explode. The FEC is $\tilde{L}_\nu\tau_g-a\tilde{\kappa}+\tilde{W}_b+b \tilde{R}_r^r >c$ and depends upon four dimensionless parameters only: 1. net neutrino heating deposited in the gain region: $\tilde{L}_\nu \tau_g = L_{\nu} \tau_g R_{\rm NS}/ ( G \dot{M} M_{\rm NS})$, 2. neutrino opacity $\tilde{\kappa} = \kappa \dot{M} / \sqrt{G M_{\rm NS} R_{\rm NS}}$ that parameterizes the neutrino optical depth in the accreted matter near the neutron-star surface, 3. the integrated buoyant driving, $\tilde{W}_b = W_b R_{\rm NS}/ (G M_{\rm NS} |\dot{M}|)$, and 4. the radial component of the Reynolds stress, $\tilde{R}_{r}^r = R_{r}^r R_{\rm NS} / (G M_{\rm NS})$. The FEC promises to be an accurate explosion condition for multi-dimensional simulations as well as being useful diagnostic to measure a "distance" to explosion. I will present a progress in validating the FEC with multi-dimensional simulations and discuss potential to expand the model by including additional effects that may be important to predict explosions and the resulting compact object properties.
Organizers: Irene Tamborra, Mariam Gogilashvili, Johan Samsing, Chris Tiede