Princeton University Astroplasmas Special Seminar

Ultra High Energy (UHE) cosmic rays (≈ 1020 eV) may be produced by known processes of acceleration by plasma turbulence in magnetized jets produced by Active Galactic Nuclei (AGNs). A simple model in which turbulence is represented as hyper-resistivity in Ohm’s Law yields several predictions in sufficient agreement with observations to motivate further investigation. Besides jet dimensions, these predictions include the unique extra-galactic cosmic ray energy spectrum (∝ 1/E3) and a different interpretation of the synchrotron radiation by which AGN jets are observed. Crucial to the model is a new theory of jet propagation whereby un-collimated jets generated by General Relativistic MHD simulations evolve to a highly collimated structure, finally evolving at speed 0.01c that explains jet dimensions, while relativistic acceleration parallel to field lines yields both cosmic rays and synchrotron radiation. References: [1] S. A. Colgate, T. K. Fowler, H. Li & J.Pino, 2014 ApJ 789, 144, on AGN jets [2] S. A. Colgate, T. K. Fowler, H. Li et al. 2015 ApJ 813, 136, on jet stability [3] T. K. Fowler & H. Li, 2016 J. Plas. Phys. 82, 595820513, on UHE acceleration [4] T. K. Fowler, H. Li, R. Anantua, 2019 ArXiV 2615445