parameter[lattice] = g_2
parameter[particle] = electron
parameter[geometry]=open
beginning[beta_a]=1
beginning[beta_b]=1
parameter[e_tot] =   3.1e10

incoming: em_field, descrip = '/home/dlr/g-2/magneticfield/injec_fld.dat', field_calc = custom, l = 4.395, &
       tracking_method = runge_kutta, num_steps = 100 , mat6_calc_method = tracking, ds_step=0.001

inject: line=(incoming)
use, inject