| Abstract : | Particle transport in small-scale turbulence is a topic of interest following the recent advancements in the theory of relativistic shocks and subsequent Fermi-type acceleration in such systems.
Small-scale turbulence is crucial in helping the particles complete enough Fermi cycles (upstream-downstream-upstream) for sufficient acceleration in relativistic shocks.
Here, I will discuss this small-scale turbulence, threaded by a mean magnetic field, as a possible candidate for driving re-acceleration in the non-thermal particles.
In contrast to prior research, which primarily focused on the spatial transport of particles in such turbulence, we examine the momentum transport of these particles under various turbulent conditions.
While calculating the transport coefficients, we also consider turbulence spectra that lack power at the resonant scale (or at the scale of a particle's gyro-radius).
Using quasi-linear theory, we compute the transport coefficients for this scenario and show that the averaged pitch-angle diffusion coefficient follows an inverse power-law trend with the particle Lorentz factor.
Such a trend is opposite compared to the case for large-scale turbulence.
We further study the interplay of synchrotron loss and particle escape via parallel diffusion with particle acceleration in such a scenario for some test cases.
Such an investigation is relevant to comprehend the stochastic acceleration of particles caused by the turbulent downstream of relativistic shocks. |
