Speaker
Sara Tomita
(Aoyama Gakuin University)
Description
The Weibel instability is thought to be important for
particle acceleration and generation of magnetic
fields in relativistic shocks. However, the magnetic
field produced by the Weibel instability cannot
occupy large regions because of the rapid decay.
Non-linear evolution of the Weibel instability has
been investigated in uniform plasmas or shocks
propagating into uniform plasmas so far. In order to
study non-linear evolution of the Weibel instability
in inhomogeneous background plasmas, we perform
two-dimensional particle in cell simulations. We find
that spatially anisotropic density structures produce
anisotropic velocity distributions, so that the
magnetic field fluctuations are excited by the Weibel
instability. Relativistic shocks propagating into
inhomogeneous plasmas are expected to produce
such anisotropic density structures in the
downstream region. Therefore, magnetic fields
generated by the Weibel instability could occupy
regions larger than previously thought. If so, the
maximum energy of accelerated particles would
become larger than previously thought.
| Registration number following "ICRC2015-I/" | 408 |
|---|---|
| Collaboration | -- not specified -- |
Author
Sara Tomita
(Aoyama Gakuin University)
Co-author
Yutaka Ohira
(Aoyama Gakuin University)
