Radiation from accelerated particles in relativistic jets with shocks, shear-flow, and reconnection

¹ University of Alabama in Huntsville, 320 Sparkman Drive, ZP12, Huntsville, AL 35805, USA
² Department of Physics and Astronomy, The University of Alabama, Tuscaloosa, AL 35487, USA
³ Institute of Astronomy, National Tsing-Hua University, Hsinchu, Taiwan 30013, Republic of China
⁴ Institute of Space Science, Atomistilor 409, Bucharest-Magurele RO - 077125, Romania
⁵ Department of Physics, University of Nevada, Las Vegas, NV 89154, USA
⁶ Department of Physics and Astronomy, University of Kansas, KS 66045, USA
⁷ Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
⁸ Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, 31-342 Kraków, Poland
⁹ Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen Ø, Denmark
¹⁰ LUTH, Observatore de Paris-Meudon, 5 place Jules Jansen, 92195 Meudon Cedex, France
¹¹ Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Strasse 24/25 14476 Potsdam-Golm, Germany
¹² Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
¹³ Institute for Astrophysical Research, Boston University, 725 Commonwealth Ave., Boston, MA 02215, USA
¹⁴ Instituto de Astrofísica de Andalucía, CSIC, Apartado 3004, 18080 Granada, Spain

^a e-mail: ken-ichi.nishikawa@nasa.gov

Published online: 9 December 2013

Abstract

We have investigated particle acceleration and shock structure associated with an unmagnetized relativistic jet propagating into an unmagnetized plasma for electron-positron and electron-ion plasmas. Strong magnetic fields generated in the trailing jet shock lead to transverse deflection and acceleration of the electrons. We have self-consistently calculated the radiation from the electrons accelerated in the turbulent magnetic fields for different jet Lorentz factors. We find that the synthetic spectra depend on the bulk Lorentz factor of the jet, the jet temperature, and the strength of the magnetic fields generated in the shock. We have investigated the generation of magnetic fields associated with velocity shear between an unmagnetized relativistic (core) jet and an unmagnetized sheath plasma. We discuss particle acceleration in collimation shocks for AGN jets formed by relativistic MHD simulations. Our calculated spectra should lead to a better understanding of the complex time evolution and/or spectral structure from gamma-ray bursts, relativistic jets, and supernova remnants.