Astrophysical Wake Acceleration Driven by Relativistic Alfvenic Pulse Emitted from Bursting Accretion Disk

Toshikazu Ebisuzaki
Computational Astrophysics Laboratory | RIKEN
Tuesday, February 25, 2020
11:00 am
FRH 4179
We consider that electromagnetic pulses produced in the jets of this innermost part of the accretion disk accelerate charged particles (protons, ions, electrons) to very high energies including energies above 1020 eV for the case of protons and nucleus and 1012-15 eV for electrons by electromagnetic wave-particle interaction. The episodic eruptive accretion in the disk by the magneto-rotational instability gives rise to the strong electro-magnetic pulses, which act as the driver of the collective accelerating pondermotive force. This pondermotive force drives the wakes. The accelerated hadrons (protons and nuclei) are released to the intergalactic space to be ultra-high energy cosmic rays. Some of them collide with the protons in the interstellar medium to produce secondary particles, such as neutrinos and gamma-ray photons. The high-energy electrons, on the other hand, emit photons in the collisions with electromagnetic perturbances to produce various non-thermal emissions (radio, IR, visible, UV, and gamma-rays) of active galactic nuclei. Applying the bow wakefield acceleration theory to nine candidate galaxies (NGC253, M82, NGC4945, NGC1068, NGC6814, Cen A, M87, For, A, and Cen B), we find two starburst galaxies (NGC253, M82), one Seyfert galaxy (NGC4945), and one radio galaxy (Cen A) are promising as UHECR sources. The sky map of these four galaxies is consistent to the arrival direction analysis of the UHECRs. In particular, M82 seams responsible to the northern hot spot suggested by TA group. Electrons are also accelerated by the same wakefield to produce high energy gamma-rays. Accelerated protons can emit high energy neutrinos though the collisions with the protons in the interstellar medium. We estimate the gamma-ray and neutrino flux from the possible UHECR sources. Finally, we suggested that galactic microquasars such as Cyg X-1, Cyg X-3, SS433, GX3+1, or GX339-4, which distributes in the galactic disk and central region of our Milky Way Galaxy can be promising neutrino sources.

Toshikazu Ebisuzaki1 and Toshiki Tajima2
1RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako 351-1198, Japan,
2Depart. of Physics and Astronomy, University of California, Irvine, CA 92679, USA,
Franklin Dollar