The particle's radius of curvature  is proportional to its momentum perpendicular to the beam (i.e. transverse momentum or ) according to the formula  (where  is the particle's charge and  is the magnetic induction), while the degree to which it drifts in the direction of the beam axis gives its momentum in that direction.
The radius of curvature for this particle is directly related to its perpendicular momentum (transverse momentum or ) via the equation , where  signifies the particle's charge and  stands for the magnetic field strength. The degree of drift parallel to the beam axis reflects its momentum in that direction.