Synchrotron radiation by slowly rotating fermions

TL;DR

This paper investigates how slow, classical rotation of a charged fermion in a magnetic field affects synchrotron radiation, revealing that rotation can significantly modify the radiation intensity depending on various parameters.

Contribution

It provides an exact solution of the Dirac equation for a rotating fermion in a magnetic field and analyzes the impact of rotation on radiation spectrum and chirality.

Findings

Rotation can enhance or suppress radiation depending on orientation and charge.

Radiation intensity increases with particle energy due to rotation.

Explicit numerical results demonstrate the effect of rotation on synchrotron radiation.

Abstract

We study the synchrotron radiation emitted by a charged fermion, rotating as a part of a larger system, in a constant magnetic field $B$ parallel to the axis of rotation. The rotation is classical and independent of the magnetic field. The angular velocity of rotation $\Omega$ is assumed to be much smaller than the inverse magnetic length $\sqrt{qB}$ which allows us to ignore the boundary effects at $r=1/\Omega$. We refer to such rotation as slow, even though in absolute value it may be an extremely rapid rotation. Using the exact solution of the Dirac equation we derived the intensity of electromagnetic radiation, its spectrum and chirality. We demonstrate by explicit numerical calculation that the effect of rotation on the radiation intensity increases with the particle energy. Depending on the relative orientation of the vectors $\bf\Omega$ and $\bf B$ and the sign of the electric charge, the rotation can either strongly enhance or strongly suppress the radiation.