Centrifugally driven electrostatic instability in extragalactic jets

Monthly Notices of the Royal Astronomical Society

Mahajan

Machabeli

et al. 2014

Self Cite

A novel model of particle acceleration in the magnetospheres of rotating active galactic nuclei (AGN) is constructed.The particle energies may be boosted up to 10 21 eV in a two step mechanism: In the first stage, the Langmuir waves are centrifugally excited and amplified by means of a parametric process that efficiently pumps rotational energy to excite electrostatic fields. In the second stage, the electrostatic energy is transferred to particle kinetic energy via Landau damping made possible by rapid "Langmuir collapse". The time-scale for parametric pumping of Langmuir waves turns out to be small compared to the kinematic time-scale, indicating high efficiency of the first process. The second process of "Langmuir collapse" -the creation of caverns or low density regions -also happens rapidly for the characteristic parameters of the AGN magnetosphere. The Langmuir collapse creates appropriate conditions for transferring electric energy to boost up already high particle energies to much higher values. It is further shown that various energy loss mechanism are relatively weak, and do not impose any significant constraints on maximum achievable energies.

Section: Centrifugal Excitation Of Langmuir Wavesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Extremely efficient Zevatron in rotating AGN magnetospheres

Monthly Notices of the Royal Astronomical Society

Mahajan

Machabeli

et al. 2014

Self Cite

“…In this section we consider a slightly moderate mechanism of acceleration. In particular, in [6,7] we have shown that rotation energy might be very efficiently pumped into that of Langmuir waves. On the next stage, under certain conditions, energy of electrostatic modes might be converted into energy of plasma particles.…”

Section: Acceleration Via Damping Of Centrifugally Excited Langmmentioning

confidence: 97%

New mechanism of acceleration of particles by stellar black holes

2017

Int. J. Mod. Phys. D

In this paper we study efficiency of particle acceleration in the magnetospheres of stellar mass black holes. For this purpose we consider the linearized set of the Euler equation, continuity equation and Poisson equation respectively. After introducing the varying relativistic centrifugal force, we show that the charge separation undergoes the parametric instability, leading to generation of centrifugally excited Langmuir waves. It is shown that these waves, via the Langmuir collapse damp by means of the Landau damping, as a result energy transfers to particles accelerating them to energies of the order of 10 16 eV.

“…This method was applied to AGN jets in Ref. 9 and the stability problem of the rotation-induced electrostatic waves has been studied. The CF is significant also for inducing the CDI.…”

Section: Introductionmentioning

confidence: 99%

On the Role of the Curvature Drift Instability in the Dynamics of Electrons in Active Galactic Nuclei

2013

Int. J. Mod. Phys. D

We study the influence of the centrifugally driven curvature drift instability (CDI) on the dynamics of relativistic electrons in the magnetospheres of active galactic nuclei (AGN). We generalize our previous work by considering relativistic particles with different initial phases. Considering the Euler, continuity, and induction equations, by taking into account the resonant conditions, we derive the growth rate of the CDI. We show that due to the centrifugal effects, the rotational energy is efficiently pumped directly into the drift modes, that leads to the generation of a toroidal component of the magnetic field. As a result, the magnetic field lines transform into such a configuration when particles do not experience any forces and since the instability is centrifugally driven, at this stage the CDI is suspended.