NBIA Seminar: Annika Rudolph

Gamma-Ray Bursts (GRBs), which are among the most energetic events in our Universe, have long been discussed as potential sources of Ultra-High-Energy Cosmic-Rays (UHECRs). This paradigm is however challenged by the lack of high-energy neutrinos detected by IceCube that could be correlated with known GRBs. In this talk, I will summarize and put into context different scenarios that may reconcile GRBs as potential sources of UHECRs, assuming a multi-zone internal shock scenario for the prompt phase of the event. Starting with the diffuse flux constraints, I will introduce a fit to the UHECR spectrum (as observed by the Pierre Auger Observatory) with the population of conventional long GRBs. I will then discuss the (single-source) multi-wavelength and neutrino signatures of cosmic ray protons in energetic GRBs, including GRB 221009A. Finally, I review the class of low-luminosity GRBs as potential sources of UHECRs and Very-High-Energy photons.