7.23. [ T-4Dtrack ] section

This tally outputs particle track information (position and time). By loading the output file into the Particle tracks tab of PHIG-3D, the trajectories can be visualized on the geometry.

Table 7.23.1 file

value

explanation

file name

Output file name.
Table 7.23.2 reg

value

explanation

all (default)

Specify the region number for writing out tracks. Refer to the common tally parameter description for the format.
Table 7.23.3 part

value

explanation

all (default)

Specify the particles for which to write out tracks. If not specified, tracks for all particles will be written out. If part includes nucleus, unstable nuclei will also be included in the output. However, only nuclei with half-lives between HalfLifeMin and HalfLifeMax will be considered. Refer to Section 6.7.1 for the format.
Table 7.23.4 stepminEM

value

explanation

0.0 (default)

Minimum step distance (cm) for electrons, positrons, and photons. Adjusting this value can reduce the data size significantly without compromising the quality of the visualizing using PHIG-3D. See the following 1 for details.
Table 7.23.5 SkipRate

value

explanation

0.0 (default)

Specify the ratio for skipping the output of particle track endpoints. This setting applies to all particles. Set a value between 0 and 1. For example, if SkipRate=0.9 is specified, the output of endpoints will be skipped with a 90% probability. The size of the output file will be approximately (1 - SkipRate) times the original size. For exceptions to skipping, see 2 below.
Table 7.23.6 SkipRate-of(kf-code)

value

explanation

0.0 (default)

Apply SkipRate only to particles specified by kf-code. For example, if SkipRate-of(2112)=0.9 is specified, the output of endpoints for neutrons will be skipped with a 90% probability. If both SkipRate and SkipRate-of are set simultaneously, the value of SkipRate-of takes precedence.

  1. A particle track is essentially composed of continuous steps. The mean free paths of electrons, positrons, and photons are generally very small, so writing out every step would result in a very large data size. Therefore, to save data size, steps whose distance from the starting point of a step is less than stepminEM are not written out.

  2. The output of track points is not skipped if any of the following three conditions are met:

    1. The particle reaches the energy cutoff.

    2. The particle reaches the boundary of a region.

    3. An interaction occurs, and the number of final states is 2 or more.

Table 7.23.7 HistoryMax

value

explanation

None (default)

The maximum number of events to write out. If omitted, all events are written out.
Table 7.23.8 HistoryFile

value

explanation

file name

Specifies the file name containing the event numbers to be written out. If not specified, all events are written out. File structure: Write the NOCAS (event number) and NOBCH (batch number) of the desired event on each line (Example 1). The numbers can be read in real number format, so dump data files specifying NOCAS and NOBCH can also be loaded.
Table 7.23.9 format

value

explanation

t4d (default)

Specify the output format. Output in t4d format. For details, refer to /phits/utility/t-4dtrack/T4D-format/readme-en.pptx.

pict

Output in pict format used by EGS5.
Table 7.23.10 verbose

value

explanation

0

Specify the output level. For details, refer to /phits/utility/t-4Dtrack/format/readme-en.pptx. Output the minimum necessary information for track display in PHIG-3D.

1 (default)

Also output track cell information and other details. For examples of how to use cell information, see /phits/utility/t-4Dtrack/OriginTrackFinder/readme-en.pptx.

2

Output counter information and more. When outputting counter values, it is necessary to use ctmin or ctmax in a separate tally.
Table 7.23.11 precision

value

explanation

6 (default)

Number of digits for outputting real numbers.

An example of the input for the file specified by HistoryFile:

Listing 7.23.1 Example of HistoryFile input
  # NOCAS  NOBCH
        1      1
        2      1
        3      1
        1      2
        2      2
        3      2
Table 7.23.12 PinnedOption

value

explanation

0 (default)

Choose whether to keep (pin) a specified particle in the visualization after it stops due to falling below the energy cutoff, instead of immediately removing it. The duration for which it remains can be specified. Do not pin.

1

Pin generated nuclei. The target nuclei can be specified by their half-life.

2

Pin particles specified in PinnedParticles.
Table 7.23.13 PinnedTimeOption

value

explanation

0 (default)

Specify the type of duration for pinning. Fixed duration. Specified by PinnedTimeFix.

1

aHalf x (the half-life of an unstable nucleus)

2

max(0, aHalf x log10(half-life/s)+**bHalf**) (ns)
Table 7.23.14 PinnedTimeFix

value

explanation

10.0 (default)

Fixed pinning duration (ns). Used with PinnedTimeOption = 0.
Table 7.23.15 aHalf

value

explanation

1.0 (default)

Scale parameter for half-life. Used with PinnedTimeOption = 1,2.
Table 7.23.16 bHalf

value

explanation

0.0 (default)

Scale parameter for the logarithmic term of the half-life. Used with PinnedTimeOption = 2.
Table 7.23.17 HalfLifeMin

value

explanation

1.0e-22 s (default)

Minimum half-life for targeted unstable nuclei. Used with part = nucleus, PinnedTimeOption = 1,2. Enter a number followed by at least one space, then enter the unit of time. Available units are s, min, h, d, y, representing seconds, minutes, hours, days, and years, respectively.
Table 7.23.18 HalfLifeMax

value

explanation

3.0e+32 s (default)

Maximum half-life for targeted unstable nuclei. Used with part = nucleus, PinnedTimeOption = 1,2. The method of entering the value is the same as for HalfLifeMin.
Table 7.23.19 PinnedParticles

value

explanation

None (default)

Enter the names or kf codes of the particles to be pinned. If entering multiple, separate them with spaces.