Detector Tallies

Like Object tallies, detector tallies are associated with Blender objects, from which the position and region size (if needed) are obtained according to the corresponding object's bounding box. Additionally, multiple tallies of the same type can be defined within the same Blender object, for example, to use different scoring mesh bins. However, this type of tally must necessarily be associated with a material body that has the detector flag enabled in the Body properties. Therefore, the tally is enabled for all bodies sharing the same detector index.

For tally types that affect a limited spatial region (instead of the entire detector volume), note that the defined region includes only the body bounding box of the object where the tally is defined.

Like object-based tallies, these tallies can be created and removed from the panel object > Tally Properties:

Detector Tallies

Regarding the naming of tallies, the final name is created according to the following pattern:

{Object Name}_{index}_{Tally Name}

here: - Object Name is the name of the Blender object. - index corresponds to the tally index within the specific type. - Tally Name is the name specified by the user for this tally.

The following object tallies can be defined within the plugin:

Impact Detector

This tally is capable of measuring different magnitudes: fluence, particle energy, energy deposition, and particle age spectra. Each magnitude is described below:

  • Fluence Spectrum
    Measures the spectral fluence integrated over the detector volume, expressed in cm/eV. The output file provides the fluence for each particle type as well as the total fluence within the specified detector.

  • Energy Spectrum
    Reports the energy spectrum of particles entering the specified detector volume. Particles generated inside the detector, such as secondary particles, are not included in this tally. The units are given in 1/(eV·history). The output file contains the energy spectrum for each particle type.

  • Age Spectrum
    Records the age distribution of particles impacting the detector, with units in 1/(seconds·history). The output file contains the probability distribution across different time intervals for all simulated particles. Notice the particle age will be calculated only if it is enabled in Source Parameters.

  • Energy Deposition Spectrum
    Reports the energy deposition spectrum measured in the specified detector. The units are given in 1/(eV·history). The output file contains the probability distribution across energy intervals, considering all simulated particles.

Each magnitude can be enabled or disabled using the corresponding toggle in the tally panel. Additionally, a linear or logarithmic scale can be used for each case. To configure the recording histograms, the following parameters must be set:

  • Energy
    Energy parameters specify the energy range and bins for all energy-based magnitudes. Additionally, energy range limits also the particles to be recorded for age spectrum.

    • Min
      Minimum energy to be recorded, in eV.
    • Max
      Maximum energy to be recorded, in eV.
    • Bins
      Number of energy bins.

  • Age
    Age parameters specify the time range and bins for the Age Spectrum. These are only required if the Age Spectrum is enabled.

    • Min
      Minimum particle age to be recorded, in seconds.
    • Max
      Maximum particle age to be recorded, in seconds.
    • Bins
      Number of age bins.

Spatial Distribution

This tally records the energy spectrum of particles reaching a specified detector within a spatial 3D grid. Like other impact detectors, particles created inside the detector will not be recorded. The available configuration parameters are as follows:

  • Energy
    Energy parameters specify the energy range and bins to score the spectrum.

    • Min
      Minimum energy to be recorded, in eV.
    • Max
      Maximum energy to be recorded, in eV.
    • Bins
      Number of energy bins.

  • Spatial
    Spatial parameters specify the number of bins, in each axis, for the 3D spatial grid.

    • X Bins
      Number of bins in the X-axis.
    • Y Bins
      Number of bins in the Y-axis.
    • Z Bins
      Number of bins in the Z-axis.

  • Particle Type
    Specifies the particle type to be recorded. Other types will be ignored by the tally.

  • Coordinates
    If enabled, the coordinates (X, Y, and Z) will be printed alongside the results, in cm.

  • Print Bins
    If enabled, the bin indexes in the X, Y, and Z axes will be printed alongside the results.

PSF

This tally generates a particle phase space file (PSF) storing all particles impacting the specified detector. Additionally, the impacting particles can be filtered by energy range and particle type. The configuration parameters are described below:

  • Min
    Minimum particle energy to be recorded, in eV.

  • Max
    Maximum particle energy to be recorded, in eV.

  • Gammas
    Enable/disable gamma recording.

  • Electrons
    Enable/disable electron recording.

  • Positrons
    Enable/disable positron recording.

Angular Detector

This tally reports the angular energy spectrum in a specified detector. In this tally, the polar and azimuthal angles of impacting particles are defined relative to the Z-axis (0, 0, 1) and the particle's direction. Therefore, these angles are not related to the detector's orientation. The recorded particles are filtered by energy and angular intervals. The energy spectra of particles are tallied in units of 1/(eV·sr·particle). Below are the parameters used to configure this tally:

  • Energy
    Energy parameters specify the energy range and bins to score the spectrum.

    • Min
      Minimum particle energy to be recorded, in eV.
    • Max
      Maximum particle energy to be recorded, in eV.
    • Bins
      Number of energy bins.

  • Polar Angle
    Defines the polar angle interval to be recorded.

    • Min
      Minimum polar angle, in degrees.
    • Max
      Maximum polar angle, in degrees.

  • Azimuthal Angle
    Defines the azimuthal angle interval to be recorded.

    • Min
      Minimum azimuthal angle, in degrees.
    • Max
      Maximum azimuthal angle, in degrees.