Pseudopospieszność

thumb|right|Pseudorapidity values shown on a polar plot. In particle physics, an angle of zero is usually along the beam axis, and thus particles with high pseudorapidity values are generally lost, escaping through the space in the detector along with the beam. thumb|right|As polar angle approaches zero, pseudorapidity tends towards infinity. In experimental particle physics, pseudorapidity, \eta, is a commonly used spatial coordinate representing the angle of a particle relative to the beam axis. It is defined as \eta \equiv -\ln\left[\tan\left(\frac{\theta}{2}\right)\right], where \theta is