Gyroradius

The gyroradius (also known as radius of gyration, Larmor radius or cyclotron radius) is the radius of the circular motion of a charged particle in the presence of a uniform magnetic field. In SI units, the non-relativistic gyroradius is given by

where ${\displaystyle m}$ is the mass of the particle, ${\displaystyle v_{\perp }}$ is the component of the velocity perpendicular to the direction of the magnetic field, ${\displaystyle q}$ is the electric charge of the particle, and ${\displaystyle B}$ is the magnetic field flux density.

The angular frequency of this circular motion is known as the gyrofrequency, or cyclotron frequency, and can be expressed as

in units of radians/second.