Faisceau de protons focalise par un B constant

-- Mass of particules : 1.6726e-27
-- Charge of particles : 1.6022e-19
-- Permittivity of free space : 8.8542e-12
-- Light velocity : 2.9979e+08
-- Energy of the beam (eV) : 5000000
-- Current of the beam (A) : 0.1
-- Lenght of one period (m) : 0.4196
-- x radius of the beam (m) : 0.0099548918
-- y radius of the beam (m) : 0.0099548918
-- Tune depression in x : 0.700342
-- Tune depression in y : 0.700342