Wakefield Acceleration in a Jet from a Neutrino Driven Accretion Flow around a Black Hole

We have investigated electromagnetic pulses in a jet from a neutrino driven accretion flow (NDAF) around a black hole. NDAFs are massive accretion disks of accretion rates M ̇ ≈ 0.01−10M⊙/s for black holes of several solar masses M ≤ 10M⊙, such extreme accretions are investigated as a model of gamma-ray bursts (GRBs) as well as supernovae and hypernovae. Recently, Ebisuzaki & Tajima 2019 (ET19) have proposed a model of acceleration mechanism of charged particles to very high energies ∼ 10²⁰ eV by electromagnetic wave-particle interaction. If episodic eruptive accretions generate Alfv ́enic pulses along large-scale structured magnetic field in the jet, such Alfv ́enic pulses act as a driver of the collective accelerating pondermotive forces which drive the wakes whose direction is parallel to the motion of particles. Because the wakes propagate at the same speed with the particles, the so-called wakefield acceleration has a robust built-in coherence by the acceleration system itself.

In this study we extend a model of the accretion disk presented by ET19 into a NDAF. We estimate the energy flux of both the electro-magnetic wave pulses and neutrino emissions from the NDAFs. We find that the total luminosity of waves L_wave = M ̇ c²/??√18α²β³ and the that of neutrinos L_ν = M ̇ c²/4 where α and β are the viscosity parameter and the plasma-β of the disk, respectively. The properties of the NDAFs and magnetically driven jets as well as the maximum energy of accelerated charged particles will be discussed.