Simona Pacuraru "Magnetic field evolution during tidal disruption events"

Wednesday 4 Feb 2026, 12:30 → 14:00 Europe/Rome

A tidal disruption event (TDE) occurs when a star is torn apart by the strong tidal pull of a supermassive black hole residing at the center of a galaxy. During this event, the stellar magnetic field gets transferred to the stream debris formed from the disruption, taking part in the subsequent evolution of the TDE. Making use of magneto-hydrodynamic simulations and a simplified semi-analytical model, I studied the early evolution of the debris stream around the black hole in the presence of magnetic fields. I will present the results from this work, focusing on the dynamical effect of magnetic fields on gas through magnetic pressure. For strongly magnetized stars, the magnetic field can become dynamically important, causing a fast increase in the stream width, an effect that may impact the subsequent gas evolution. Furthermore, my characterization of the magneto-hydrodynamic properties of the returning stream can be used in future studies of the later phases of a TDE. These will be crucial to determine the role of magnetic fields in providing the source of viscosity when an accretion disc has formed, thus affecting observable signatures such as X-ray radiation and relativistic outflows.