# LARMOR RADIUS

## We introduce here a simple method to calculate the Larmor radius of
a charged particle in space, located in the Earth's vicinity. We calculate Earth
magnetic field starting from particle posistion
in the shifted tilted approximation as seen below.

## Then Larmor radius is calculated with this simple formula

## The rigidity is defined as

## where p is the momentum, c is the speed of light, e is the electron charge, Z is the particle charge number, A is the mass number and kinetic and rest energy are per nucleon (if energy is in eV then rigidity is in Volts)

Last updated on 17-JUL-2002 by Davide Grandi