This keyword enables the total energy-integrated projectile flux (per square cm per second) to be specified for a particular time interval. Note that if several consecutive time intervals require the same flux value, it need be entered only once for these intervals. Setting a total flux value equal to 0 gives a purely decay time-step, but flux must be set to a non-zero positive value before the first irradiation step and must be set to zero before using the ZERO keyword.
Example usage, where the flux is set to 1.0E10, then 1.0E5 and then 0.0 particles per cm squared per second:
< -- Control phase -- > ... CUMFYLD FISPACT * Title of the simulation < -- Initial phase -- > ... FLUX 1.0E10 ATOMS < -- Inventory phase -- > TIME 1.0 HOURS ATOMS FLUX 1.0E5 TIME 1.0 HOURS ATOMS FLUX 0.0 ZERO << cooling periods >> TIME 1.0 HOURS ATOMS ...