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- 03.05. Jordan Simpson (IFY, NTNU): Cataclysmic variables with HiPERCAM
Abstract: Cataclysmic variables (CVs) are close interacting binary systems consisting of a white dwarf star (primary) accreting matter from a low-mass companion (secondary). As the end-state of many main sequence binaries, and potential progenitors to Type Ia supernovae, CVs form a crucial stage in the evolution of a wide variety of systems. The classical theory of CV evolution has persisted for over 40 years, despite its continuing failures to explain observations. Recently, a new empirical model has emerged that potentially explains many issues in CV evolution - however, a physical basis for this model is still needed. Using the ultra-fast quintuple-band imager HiPERCAM, along with advanced modelling techniques, the team at Sheffield (and collaborators) measures CVs with unprecedented precision to test this new model and ultimately resolve the long-standing problems in CV evolution once and for all.
- 10.505. , Alice HardingHarding (Los AlamosLANL): ??? Abstract: High-energy emission from spider binaries
Abstract: Compact binary systems containing rotation-powered millisecond pulsars with powerful winds that interact with their companions produce shocks that can accelerated particles to very high energies. The pulsar winds also heat and ablate the companion stars, and are appropriately named Black Widow and Redback systems. The Fermi Gamma-Ray Space Telescope has discovered most of the present population of 32 Black Widows and 13 Redbacks. I will discuss the acceleration and radiation from the intrabinary shocks in such systems and present a model for orbitally modulated emission from X-rays to Very-High-Energy gamma-rays.nds and outflows are ubiquitous at several scales throughout the Cosmos. They often develop a bubble structure characterized by strong shocks and turbulence where high-energy particles can be efficiently produced. I will present a model in which diffusive shock acceleration is a key process to energize particles in such astrophysical winds.I will show some model applications in the context of young massive stellar clusters, starburst galaxies and active galactic nuclei andI will discuss the associated multi-messenger implications in terms of high-energy photons, neutrinos and escaping cosmic rays.
slides
- 23.05., Mathias Pavely Noedtvedt (IFY, NTNU): ??? Abstract:
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- 10.06. Jens 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.
- tbd: . Kari (IFY, NTNU): ??
Abstract: On
- tbd: . Vittoria Vecchiotti (IFY, NTNU): ??
Abstract: On
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