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- 14.11. Raphaël Mignon-Risse (IFY, NTNU): Oes
Abstract: Cle.
slides Towards multi-messenger observations of accreting binary black holes
Abstract: Despite the re-birth of multi-messenger astronomy, no unambiguous electromagnetic (EM) counterpart to binary black hole (BBH) merger has been reported. Supermassive BBHs are potential targets because they should be embedded in gas-rich media provided by their host galaxies merging together. However, their accretion properties and EM/multi-messenger signatures are not firmly identified because few numerical codes are able to model accretion and emission around BBHs in General Relativity (GR). In this talk, I will present e-NOVAs, standing for "extended Numerical Observatory for Violent Accreting systems" as it has been recently extended to work with any type of spacetime. It is the first European code to evolve an analytical BBH metric as it solves the equations of GR-magnetohydrodynamics and to compute synthetic observations in the same metric via GR ray-tracing. Using e-NOVAs, I will study a BBH circumbinary disk evolution and its EM observables. I will briefly present the accretion structures that could potentially help us distinguishing BBHs. I will show if their spectro-timing properties could be used as an EM signature allowing us to distinguish BBHs from other transient sources in the future. Finally, I will briefly present the first project I will be carrying out here at NTNU.
slides
Towards multi-messenger observations of accreting binary black holes
- tbd. Jens Oluf Andersen (IFY, NTNU): Pion condensation and pion stars
Abstract: In this talk I will discuss pion condensation in the context of two and three-flavor chiral perturbation theory. I will present results for quark and pion condensates as functions of the isospin chemical potential. The results compare favorably to those of lattice QCD. As an application, I will discuss pion condensation in a dense neutrino cloud and the possibility of pion stars. These are compact objects with a mass up to 20 solar masses and radii of up to 140km.
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