Event Calendar

Location: MP 15th Floor Conf Room

Title: Nature’s Death Stars: A Discussion of Supermassive Black Holes, Relativistic Jets, and The Event Horizon Telescope.

Abstract: What are relativistic jets made of? The answer is central to our understanding of how supermassive black holes influence their surrounding galactic environments. In this talk I will present my research on the composition of relativistic jets (and in particular blazars) within the context of the Event Horizon Telescope (EHT) collaboration. Blazars represent an extreme subclass of active galactic nuclei (AGN), in which an accreting supermassive black hole launches and powers a relativistic jet of magnetized plasma that is closely aligned to our line-of-sight. Blazar jets: (i) shine across the entire electromagnetic spectrum (from low-frequency radio waves to high-energy gamma-rays), (ii) exhibit dramatic flares, and (iii) dominate the high-energy extragalactic sky. Very long baseline interferometric (VLBI) arrays (such as phased ALMA \& The Event Horizon Telescope) are capable of imaging the polarized synchrotron emission emanating from the innermost regions of relativistic blazar jets with unprecedented angular resolution and sensitivity. In particular, the linearly and circularly polarized synchrotron emission from blazars carry imprints of both the strength and orientation of the collimating magnetic fields as well as the plasma content of each jet. In parallel to these advances in VLBI imaging, modern computational resources now support the production and execution of increasingly sophisticated 3D numerical jet simulations, from semi-analytic shock-in-jet and turbulence models, to relativistic magneto-hydrodynamic (RMHD) and particle-in-cell (PIC) jet plasma simulations. My research focuses on bridging the gap between these 3D relativistic jet simulations and mm-wave global VLBI observations of blazar jets through the application of ray-tracing and polarized radiative transfer. In this talk, I will present a suite of relativistic jet simulations that attempt to place firmer constraints on the as yet unknown plasma content of black hole jets.

Host: Almog

Location: MP1318A

Weekly paper discussion focussing on pulsars, compact objects, and propagation effects.

For a list of upcoming discussions, see:
https://docs.google.com/spreadsheets/d/1KEyKBCmeGFUmMoiYKuHEDguCv9OOrEZqm3A6GM1Slk0/edit?usp=sharing 

If you would like to sign up for the presenter rota, email: simard@astro.utoronto.ca Location: CITA lounge

Location: MP1318A

The schedule of speakers: https://tinyurl.com/cosmo-rota  
Location: 15th floor conference room

Title: Higgs vacuum decay with primordial black holes

Abstract: Phase transitions are part of everyday life, yet are also believed to be part of the history of our universe, where the nature of particle interactions change as the universe settles into its vacuum state. The recent discovery of the Higgs and its mass suggests that our vacuum may not be entirely stable, and that a further phase transition could take place. My talk will review how we find the probability of these phase transitions and I will discuss how black holes alter this rate. This leads to a constraint either on primordial black hole formation or the Higgs potential.

Host: Tom

Location: MP1318A

The schedule of speakers: https://tinyurl.com/cita-blackboard Location: MP 1318A

Location: MP 15th Floor Conf Room

Title: TBA

Abstract: TBA

Host: Pavel

Weekly paper discussion focussing on pulsars, compact objects, and propagation effects.

For a list of upcoming discussions, see:
https://docs.google.com/spreadsheets/d/1KEyKBCmeGFUmMoiYKuHEDguCv9OOrEZqm3A6GM1Slk0/edit?usp=sharing 

If you would like to sign up for the presenter rota, email: simard@astro.utoronto.ca Location: CITA lounge

Open discussion of stars- and planets-related topics or more specialized discussion of dynamics-related papers on alternating weeks. See here for details. Location: MP 1318A

The schedule of speakers: https://tinyurl.com/cosmo-rota  
Location: 15th floor conference room

Title: Core-collapse supernova physics in the multi-messenger era

Abstract: Our understanding of the core-collapse supernova explosion mechanism is incomplete. While the favoured scenario is delayed revival of the stalled shock by neutrino heating, it is difficult to reliably compute explosion outcomes and energies, which depend sensitively on the complex radiation hydrodynamics of the post-shock region. The dynamics of the (non-)explosion depend sensitively on how energy is transported from inside and near the proto-neutron star to material just behind the supernova shock. While supernovae are observed daily across the electromagnetic spectrum, only second-hand information on what is driving these stellar explosions can be inferred through photons. Neutrinos and gravitational waves, emitted from the very heart of the core-collapse supernova, offer a unique opportunity to directly probe the dynamics of the central engine driving the explosion. In this talk, I will discuss how multi-messenger observations of core-collapse supernovae - combined with a broad comprehension of the underlying physics of stellar collapse - can be used to directly probe core-collapse supernova theory, and infer the properties of nascent compact objects therein borne.

Location: MP1318A

Location: MP1318A

The schedule of speakers: https://tinyurl.com/cita-blackboard Location: MP 1318A