Dissipation effects in the ratchetlike Fermi acceleration

Abstract

Ac driven asymmetric pulses can be used to control the Fermi acceleration between three different motions, $\mathbf{A}:$ the {\it accelerated} mode; $\mathbf{D}:$ the {\it decelerated} mode and $\mathbf{H}:$ the {\it hyperaccelerated} mode. In this work we show that dissipation strongly affects the particles velocity, reducing the possibility for an accurate control of the dynamics. The saturation time, where the mean velocity starts to be constant due to dissipation, decays with a power law $\sim {\gamma }^{-\beta }$, where $\gamma$ is the dissipation parameter and $\beta$ is close to 1. The value of the saturated mean velocity also decays with a power law with exponent $\beta \sim 0.6$ for the case $\mathbf{H}$, and $\beta \sim 0.3$ for the case $\mathbf{A}$. In the case $\mathbf{D}$ this velocity is almost constant for small dissipations.

5 pages and 4 figs. Accepted in Mathematical Problems in Engineering

References in corpus (9)

• The Fermi-Ulam Accelerator Model Under Scaling Analysis
• Acceleration of Particles by Oblique Shocks and Cosmic Ray Spectra around the Knee Region
• Ion leakage from quasiparallel collisionless shocks: implications for injection and shock dissipation
• Hyperacceleration in a stochastic Fermi-Ulam model
• The Fermi accelerator in atom optics
• Increasing thermoelectric efficiency towards the Carnot limit
• Chaotic motion at the emergence of the time averaged energy decay
• Ratchetlike pulse controlling the Fermi deceleration and hyperacceleration
• Cosmic-Ray Momentum Diffusion In Magnetosonic Versus Alfvenic Turbulent Field