Astronomy & Astrophysics Seminar: Quasi-periodic X-ray Eruptions from Stars Inspiraling Towards a Supermassive Black Hole

Zoom: https://tau-ac-il.zoom.us/j/89636068691?pwd=YkVoWG9laTFPZHVENWovQ1FWczUvQT09

Abstract:

Centers of galaxies are fertile environments for a variety of dynamical processes, owing to the high density of stars and the presence of a central supermassive black hole. Stars may occasionally be deflected onto a deadly trajectory, passing too close to the central black hole where they are being tidally disrupted, or they may gently inspiral towards the black hole due to the emission of gravitational waves, until they fill their Roche lobe and shed mass towards the supermassive black hole, forming a “stellar extreme mass-ratio inspirals (EMRIs)”. I will review these processes and discuss a possible connection between stellar EMRIs and a recently discovered class of transient X-ray events, known as Quasi-Periodic Eruptions (QPEs) associated with galactic nuclei. I will conclude by discussing the predictions we make regarding the evolution of the observed QPE systems on a decade timescale, and comment on their prospects as multi-messenger targets in the era of space-based GW detectors, and all-sky X-ray surveys.

Seminar Organizer: Dr. Iair Arcavi