&envelope_tracker
  lat_file = 'dc12c.bmad'
  ey0 = 0.0e-12  ! Desired zero-current vertical excitation. If the ring has no coupling
                 ! and no vertical dispersion, this sets the vertical emittance exactly.  
                 ! the excitation is generated by kicking the pypy component of the beam sigma matrix.

  include_ibs = .true.
  current = 0.002
  tail_cut = .true.

  starting_a_emit = 136.0d-12
  starting_b_emit = 1.0e-15  !10.0d-12
  starting_c_emit = 2.8e-6   !sigma_e * sigma_z

  nturns = 40000           ! Monitor emit_vs_turn.out for convergence. -1 to disable tracking.
  bend_slice_length = 0.01 ! Smaller Values improve accuracy of synchrotron radiation calcs and IBS.
  slice_length = 0.1       ! Smaller values improve accuracy of IBS (SR calc is indifferent).

  user_supplied_tunes = F  ! Set True and supply the tunes if the program cannot correctly guess the tunes.
  tune_x = 0               ! Units of rad/2pi. Set if user_supplied_tunes = T.
  tune_y = 0
  tune_z = 0
/