anchor.diff:  
                   ! Add the spawning rate (for the processor) to the running
                   ! total.
  -                rspawn = rspawn + spawning_rate(ndeath, nattempts)
  +                ! Note that 'death' in CCMC creates particles in the spawned
  +                ! list, so the number of deaths not in the spawned list is 0.
  +                rspawn = rspawn + spawning_rate(0, nattempts)
   
                   call direct_annihilation()
   
  
positive.code:                 ! This is used for accounting later, not for controlling the spawning.
                  nattempts = 2*nparticles(1)
  
                  ! Reset death counter
                  ndeath = 0
  
                  ! Allow one spawning & death attempt for each excip on the
                  ! processor.
                  do iattempt = 1, nparticles(1)
  
negative.code:         integer(lint) :: iattempt, nattempts, nparticles_old(sampling_size)
          type(det_info) :: cdet
  
          integer :: nspawned, excitation_level
          real(p) :: cluster_amplitude, pcluster
          type(excit) :: connection
  
  