&envelope_tracker
  lat_file = 'small_ring.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 = 400 !monitor emit_vs_turn.out for convergence. -1 to disable tracking.
  bend_slice_length = 0.2 !smaller values improve accuracy of synchrotron radiation calcs and IBS.
  slice_length = 0.2 !smaller values improve accuracy of IBS (SR calc is indifferent).
	regression_test = True
/