High power Cherenkov radiation from a relativistic particle rotating around a dielectric ball

TL;DR

This paper investigates how a relativistic electron rotating around a dielectric ball can produce exceptionally high power Cherenkov radiation due to electromagnetic oscillations being trapped and superimposed inside the ball, surpassing radiation in infinite media.

Contribution

It reveals the mechanism of high power Cherenkov radiation generation from a rotating electron near a dielectric sphere, highlighting the role of electromagnetic oscillation locking.

Findings

Radiation power can exceed that in infinite media by dozens of times.

High power occurs at specific harmonics with weak absorption.

Electromagnetic oscillations are partially locked inside the dielectric ball.

Abstract

Some characteristic features in the radiation from a relativistic electron uniformly rotating along an equatorial orbit around a dielectric ball have been studied. It was shown that at some harmonics, in case of weak absorption of radiation in the ball material, the electron may generate radiation field quanta exceeding in several dozens of times those generated by electron rotating in a continuous, infinite and transparent medium having the same real part of permittivity as the ball material. The rise of high power radiation is due to the fact that electromagnetic oscillations of Cherenkov radiation induced along the trajectory of particle are partially locked inside the ball and superimposed in nondestructive way.