Highly relativistic circular orbits of spinning particle in the Kerr field
Abstract
The Mathisson-Papapetrou equations in Kerr's background are considered. The region of existence of highly relativistic planar circular orbits of a spinning particle in this background and dependence of the particle's Lorentz $\ensuremath{\gamma}$ factor on its spin and radial coordinate are investigated. It is shown that in contrast to the highly relativistic circular orbits of a spinless particle, the corresponding orbits of a spinning particle are allowed in a much wider space region. Some of these orbits show the significant attractive action of the spin-gravity coupling on a particle and others are caused by the significant repulsive action. Numerical estimates for electrons, protons, and neutrinos in the gravitational field of black holes are presented.