beginning[beta_a] = 10
beginning[beta_b] = 10
beginning[p0c] = 6e6
parameter[geometry] = open
parameter[absolute_time_tracking] = T
parameter[particle] = electron

call, file = lcls_gun_solenoid.bmad

SOL1: lcls_gun_solenoid

SOL1[L] = 0.19*2
SOL1[superimpose] = T
SOL1[offset] = 0.196010
SOL1[bs_field] = 0.25
SOL1[wrap_superimpose] = False

d0: drift, L = 0.5

lat: line = (d0)

use, lat