Publications (27)
Radiation from relativistic shocks with turbulent magnetic fields
K. -I. Nishikawa, J. Niemiec, M. Medvedev +10
Using our new 3-D relativistic electromagnetic particle (REMP) code parallelized with MPI, we investigated long-term particle acceleration associated with a relativistic electron-p…
Relativistic Particle-In-Cell Simulation Studies of Prompt and Early Afterglows from GRBs
K. -I. Nishikawa, P. Hardee, Y. Mizuno +4
Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks e.g. gamma-ray bursts (GRBs) active galactic nuclei (AGNs) and microquasars commonl…
Radiation from relativistic jets in turbulent magnetic fields
K. -I. Nishikawa, M. Medvedev, B. Zhang +7
Using our new 3-D relativistic electromagnetic particle (REMP) code parallelized with MPI, we have investigated long-term particle acceleration associated with an relativistic elec…
Simulation of relativistic shocks and associated radiation
K. -I. Nishikawa, J. Niemiec, M. Medvedev +9
Using our new 3-D relativistic electromagnetic particle (REMP) code parallelized with MPI, we investigated long-term particle acceleration associated with a relativistic electron-p…
Particle Acceleration and Magnetic Field Generation in Electron-Positron Relativistic Shocks
K. -I. Nishikawa, P. Hardee, G. Richardson +3
Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., Buneman, Weibel and other two-stream instabilities)…
Particle acceleration in electron-ion jets
K. -I. Nishikawa, P. Hardee, C. B. Hededal +6
Weibel instability created in collisionless shocks is responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle (REMP)…
New Relativistic Particle-In-Cell Simulation Studies of Prompt and Early Afterglows from GRBs
K. -I. Nishikawa, J. Niemiec, H. Sol +8
Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and microquasars com…
Particle Acceleration, Magnetic Field Generation, and Associated Emission in Collisionless Relativistic Jets
K. -I. Nishikawa, Y. Mizuno, G. J. Fishman +1
Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., active galactic nuclei (AGNs), gamma-ray bursts (GRBs), and Galactic microqu…
A General Relativistic Magnetohydrodynamics Simulation of Jet Formation
K. -I. Nishikawa, G. Richardson, S. Koide +4
We have performed a fully three-dimensional general relativistic magnetohydrodynamic (GRMHD) simulation of jet formation from a thin accretion disk around a Schwarzschild black hol…
Relativistic Jet Response to Precession and Wave-Wave Interactions
P. Hardee, P. Hughes, A. Rosen +1
Three dimensional numerical simulations of the response of a Lorentz factor 2.5 relativistic jet to precession at three different frequencies have been performed. Low, moderate and…
Radiation from accelerated particles in relativistic jets with shocks, shear-flow, and reconnection
K. -I. Nishikawa, P. Hardee, B. Zhang +11
We have investigated particle acceleration and shock structure associated with an unmagnetized relativistic jet propagating into an unmagnetized plasma. Strong magnetic fields gene…
Weibel Instability Driven by Relativistic Pair Jets: Particle Acceleration, Magnetic Field Generation, and Emission
K. -I. Nishikawa, P. Hardee, C. B. Hededal +4
Shock acceleration is a ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., Buneman, Weibel and other two-stream instabilities) c…
Simulation of Relativistic Jets and Associated Self-consistent Radiation
K. -I. Nishikawa, E. J. Choi, K. Min +11
lasma instabilities excited in collisionless shocks are responsible for particle acceleration. We have investigated the particle acceleration and shock structure associated with an…
Radiation from Particles Accelerated in Relativistic Jet Shocks and Shear-flows
K. -I. Nishikawa, P. Hardee, I. Dutan +12
We have investigated particle acceleration and emission from shocks and shear flows associated with an unmagnetized relativistic jet plasma propagating into an unmagnetized ambient…
Pinpointing the TeV gamma-ray emission region in M87 using TeV and 43 GHz radio monitoring
R. M. Wagner, M. Beilicke, F. Davies +8
The TeV radio galaxy M87 is the first radio galaxy detected in the TeV regime. The structure of its jet, which is not pointing towards our line of sight, is spatially resolved in X…
Particle Acceleration, Magnetic Field Generation, and Emission in Relativistic Shocks
K. -I. Nishikawa, P. Hardee, C. B. Hededal +4
Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., Buneman, Weibel and other two-stream instabilities)…
On Dynamical Models for Radio Galaxies
J. Eilek, P. Hardee, T. Markovic +2
The tailed radio galaxies that have been called ``Type I'' are not a uniform set. To study their dynamics, we have used the Ledlow-Owen data set, which provides a new sample of 250…
Radiation from relativistic jets
K. -I. Nishikawa, Y. Mizuno, P. Hardee +7
Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and Galactic microqu…
3D Relativistic MHD Simulations of Magnetized Spine-Sheath Relativistic Jets
Y. Mizuno, P. Hardee, K. -I. Nishikawa
We have performed numerical simulations of weakly and strongly magnetized relativistic jets embedded in a weakly and strongly magnetized stationary or mildly relativistic (0.5c) sh…
3-D GRMHD Simulations of Disk-Jet Coupling and Emission
K. -I. Nishikawa, Y. Mizuno, S. Fuerst +7
We have performed a fully three-dimensional general relativistic magnetohydrodynamic (GRMHD) simulation of jet formation from a thin accretion disk around a Schwarzschild black hol…
The 2010 very high energy gamma-ray flare & 10 years of multi-wavelength observations of M 87
The H. E. S. S. Collaboration, :, A. Abramowski +442
Abridged: The giant radio galaxy M 87 with its proximity, famous jet, and very massive black hole provides a unique opportunity to investigate the origin of very high energy (VHE;…
Relativistic Shocks: Particle Acceleration and Magnetic Field Generation, and Emission
K. -I. Nishikawa, P. Hardee, G. Richardson +3
Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g.,Buneman, Weibel and other two-stream instabilities) c…
Particle acceleration, magnetic field generation, and emission in relativistic pair jets
K. -I. Nishikawa, P. Hardee, C. B. Hededal +4
Shock acceleration is a ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., Buneman, Weibel and other two-stream instabilities) c…
Particle Acceleration in Relativistic Jets due to Weibel Instability
K. -I. Nishikawa, P. Hardee, G. Richardson +3
Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, two-streaming instability,…
Magnetic field generation in a jet-sheath plasma via the kinetic Kelvin-Helmholtz instability
K. -I. Nishikawa, P. Hardee, B. Zhang +11
We have investigated generation of magnetic fields associated with velocity shear between an unmagnetized relativistic jet and an unmagnetized sheath plasma. We have examined the s…
3-D GRMHD and GRPIC Simulations of Disk-Jet Coupling and Emission
K. -I. Nishikawa, Y. Mizuno, M. Watson +4
We investigate jet formation in black-hole systems using 3-D General Relativistic Particle-In-Cell (GRPIC) and 3-D GRMHD simulations. GRPIC simulations, which allow charge separati…
Particle Acceleration and Radiation associated with Magnetic Field Generation from Relativistic Collisionless Shocks
K. -I. Nishikawa, P. Hardee, G. Richardson +3
Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, two-streaming instability,…