November 12th at 11:45am (EST) we are grateful to have Rostom Mbarek, graduate student at the University of Chicago, virtually present his research on UHECR and neutrino production in AGN jets.
Rostom’s work in this area can be found here (2019) and here (2021). Seethe end of this email for his title and abstract. In addition, Steven will discuss the recent paper on T-510, a SLAC experiment that aims to understand the radio emission from particle showers in dense material. This ultra-interesting lunch is themed towards ultra-high energy interactions.
Please, actively join us in this hybrid mode lunch. The zoom link of the Astrolunch is available on our webpage:https://sites.google.com/site/ccappastrolunch/.You are encouraged to attend in person at the Price Place.
Title: Ultra-High-Energy Cosmic Rays and Neutrinos from relativistic jets of Active Galactic Nuclei'
Abstract: In Mbarek & Caprioli (2019), we laid the groundwork for studying the espresso paradigm Caprioli (2015), a reacceleration mechanism to boost galactic cosmic rays (CRs) to Ultra-High-Energy CR (UHECR) levels. Our bottom-up approach uses realistic 3D MHD simulations of relativistic AGN jets and accounts for all of the crucial ingredients of a universal acceleration theory: injection, acceleration, and escape in realistic environments. Our results are consistent with the main features of UHECR spectra, i.e., power-law slopes, chemical composition, and anisotropy. In Mbarek & Caprioli (2021), we refine our model by including sub-grid particle scattering to model small-scale magnetic turbulence that cannot be resolved by MHD simulations, constraining for the first time one crucial but hard-to-model ingredient, and allowing us to establish the relative importance of espresso and stochastic shear acceleration in relativistic jets. Here, we analyze high-energy neutrinos produced from our accelerated UHECRs considering the effects of external photon fields, and incorporate nucleus photodisintegration. We find that UHECRs are not significantly affected by photodisintegration in AGN jets, which is consistent with Auger's detection of heavy elements at the highest energies. We also note that the source neutrino flux at E>1e17 eV is comparable to that of cosmogenic neutrinos, and that the steady neutrino emission from AGN jets cannot solely account for IceCube's signal.