Oral Presentation

Microscopic Processes in Global Relativistic Jets Containing Helical Magnetic Fields

Author(s): Ken-Ichi Nishikawa, Yosuke Mizuno, Jose L. Gómez, Charley Wthite, Jacek Niemiec, Oleh Kobzar, Martin Pohl, Ioana Duan, Asaf Pe’er, Jacob Trier Frederiksen, Åke Nordlund, Athina Meli, Helene Sol, Philip E. Hardee and Dieter H. Hartmann

Presenter: Kenichi Nishikawa (Univ. of Alabama in Huntsville)

 In the study of relativistic jets one of the key open questions is their interaction with the environment on the microscopic level. Here, we study the initial evolution of both electron–proton and electron–positron relativistic jets containing helical magnetic fields, focusing on their interaction with an ambient plasma. We have performed simulations of “global” jets containing helical magnetic fields in order to examine how helical magnetic fields affect kinetic instabilities such as the Weibel instability, the kinetic Kelvin-Helmholtz instability (kKHI) and the Mushroom instability (MI). In our initial simulation study these kinetic instabilities are suppressed and new types of instabilities can grow. In the electron-proton jet simulation a recollimation-like instability occurs and jet electrons are strongly perturbed. In the electron-positron jet simulation a recollimation-like instability occurs at early times followed by a kinetic instability and the general structure is similar to a simulation without helical magnetic field. The evolution of electron-ion jets will be investigated with different mass ratios. Simulations using much larger systems are required in order to thoroughly follow the evolution of global jets containing helical magnetic fields.