no_digested
parameter[geometry] = open
parameter[taylor_order] = 1
parameter[ptc_exact_model] = T
beginning[p0c] =   1e9
beginning[beta_a] = 10 
beginning[beta_b] = 10
beginning[alpha_a] = 0
beginning[alpha_b] = 0

particle_start[x]  = 0.00
particle_start[px] = 0
particle_start[y]  = 0.00
particle_start[py] = 0.00
particle_start[z]  =  1e-6
particle_start[pz] = 0.0
particle_start[spin_x] = 1
particle_start[spin_y] = 0
particle_start[spin_z] = 0

q: quad, l = 1, k1 = 1
rf: lcav, l = 1, rf_frequency = 1e9, gradient = 1e6
mm: match, beta_a1 = 1, beta_b1 = 11, match_end = T
l1: line = (q, rf, mm)
use, l1

expand_lattice
slice_lattice 1:2