&bbu_params
  bbu_param%lat_file_name = 'prstab2004_chrom.lat'         ! Bmad lattice file name   
  bbu_param%bunch_freq = 1.3e9                ! Freq in Hz.
  bbu_param%limit_factor = 1e1                ! Init_hom_amp * limit_factor = simulation unstable limit
  bbu_param%hybridize = False               ! Combine non-hom elements to speed up simulation?
  bbu_param%keep_overlays_and_groups = True ! Keep when hybridizing?
  bbu_param%current = 20e-3                   ! Starting current (amps)
  bbu_param%rel_tol = 1e-3                    ! Final threshold current accuracy.
  bbu_param%write_hom_info = True  
  bbu_param%drscan = True                   ! If true, do DR scan as in PRSTAB 7 (2004) Fig. 3.
  bbu_param%elname = 'T1'
  bbu_param%nstep = 50
! PRSTAB 2004
  bbu_param%begdr = 5.234
  bbu_param%enddr = 6.135

  beam_init%n_particle = 100
  beam_init%sig_e = 0.2e-3

  bbu_param%ran_seed = 1234

  bbu_param%verbose = False
  bbu_param%regression = True
/