3.7. Card 6: Irradiation and cooling times

Refer to Section 4.3 for an example utilizing these parameters.

Table 3.7.1 ITSTEP PHITS: other means

Value	Description
(D=1)	Sum of the number of irradiation periods and cooling periods.

Card 6a: Time and beam power listings

Each of the following 3 entries must be listed on a single line, separated by any nonzero number of spaces, and this sequence must be repeated ITSTEP times on ITSTEP lines.

Table 3.7.2 TBIN PHITS: same name

Value	Description
	Duration of an irradiation/cooling step. Note that these entries are not the time elapsed since the beginning of the first time step but rather the duration of each time step/bin \(\Delta t\).

Table 3.7.3 TBINU PHITS: same name

Value	Description
	Time units of TBIN expressed as a single character. Acceptable entries are seconds (s), minutes (m), hours (h), days (d), and years (y).

Table 3.7.4 BEAMPW PHITS: same name

Value

Description

Normalized beam intensity. The total beam intensity used by the code is calculated as BEAMPW \(\times\) AMP; likewise, the total neutron flux in each region is calculated as BEAMPW \(\times\) FLUXS. Thus, this allows for adjustment between full power (1.0), cooling (0.0), and beam powers above and below the nominal intensity. Setting BEAMPW=0.0 is how the cooling time-steps are distinguished from the irradiation steps.

(Note: The end of the final time step listed here is used to terminate the calculation. Output cannot be requested at times beyond the sum of all ITSTEP time step values.)