Up to now it is not yet clear what the actual composition of the jets
of Active Galactic Nuclei is.
Radiation models so far prefer either a pure leptonic or hadronic composition,
but it can be safely assumed that protons as well as electrons and
positrons are present in AGN jets.
In recent PIC simulations of colliding plasma streams pure
electron-positron [1,2,3]
or electron-proton plasmas [4] have been considered.
Our approach is now to consider mixed plasma of protons, electrons and
positrons. This will give us an
insight to the possible instabilities taking place in the mixed modes.
The interesting point is that due to the different masses the magnetic
field increase may be modified.
We have undertaken simulations of mixed mode plasmas using different
mass ratios. Our research shows
the influence of the mass ratio and the composition on the magnetic
field generated by the filamentation
instability. Also the energy spectra of high mass and low mass
particles are compared.
[1] Spitkovsky, Anatoly; On the Structure of Relativistic
Collisionless Shocks in Electron-Ion Plasmas
[2] Spitkovsky, Anatoly; Particle Acceleration in Relativistic
Collisionless Shocks: Fermi Process at Last?
[3] Silva, L. O.; Fonseca, R. A.; Tonge, J. W.; Dawson, J. M.; Mori,
W. B.; Medvedev, M. V.; Interpenetrating Plasma Shells:
Near-equipartition Magnetic Field Generation and Nonthermal Particle
Acceleration
[4] Chang, Philip; Spitkovsky, Anatoly; Arons, Jonathan; Long-Term
Evolution of Magnetic Turbulence in Relativistic Collisionless Shocks:
Electron-Positron Plasmas
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