• An NPS card specifies the number of particle histories: NPS n means that the Monte Carlo calculation stops after n source particles.

• A CTME card specifies the computer time limit (in minutes): if a run duration is greater, the Monte Carlo calculation stops.

TotNu and NoNu cards

• NoNu means that fission is treated as a simple capture; this card may be useful to see primary fission neutrons.

• TotNu has two meanings, depending on the type of calculation: (1) In KCODE mode (critical calculation), if TOTNU is not present or is present with no argument, the total neutron number (including delayed neutrons) v is used; if TOTNU is followed by NO, the prompt v is used. (2) In non-KCODE mode, if TOTNU is absent or present with NO, the prompt v is used, whereas if TOTNU is present with no argument, the total v is used.

PHYS card

This card is used as