DOSE: Total Ionizing Dose

Overview

The CREME96 DOSE program module evaluates the dose (in rads) from an input particle flux file. The DOSE program is primarily intended for evaluating the dose due to non-trapped components of the radiation environment (solar quiet fluxes and solar energetic particles.)

The DOSE module can also be used to evaluate dose due to the trapped proton fluxes produced by the CREME96/TRP program module. However, in general, such calculations are not recommended. Although the DOSE trapped proton calculations are as accurate as the underlying AP8 models allow, the CREME96/TRP module does NOT include trapped electrons. Trapped electrons often provide a significant contribution to total ionizing dose, at least for devices deployed under less than ~300 mils (~2 g/cm² Al) of shielding. Better software for calculating dose due to trapped radiation, including both electrons and protons, is available elsewhere.

The DOSE calculation integrates over all arrival directions, covering 4-pi steradians. The calculation treats the input flux as isotropic or, equivalently, as an omnidirectional average.

Inputs

To run the DOSE program module, you must:

• Select the input particle flux file:
  • The .tfx files, which contain particle fluxes after transport through shielding by the TRANS module, are the recommended starting points for DOSE calculations.
  • Flux and TRP trapped proton files may also be selected, however, in general these files should not be used, since the fluxes they contain have not been processed through shielding by the TRANS module. Using these "unshielded fluxes" can often lead to large overestimates of the dose, especially for solar particle events, which include large fluxes of low-energy particles.
• Specify the minimum and maximum atomic numbers to be included in the dose calculation.
  • The default values (0) will automatically include all of the elements found in the input particle flux file.
• Select the device material.
  • At present, only silicon is available.
• Specify the rootname of the output file. The DOSE program will automatically add the extension .dse to the filename.

Outputs

Results of the DOSE calculation will be recorded in the output file. You can download the output .dse file to your machine.

The output file will contain the average dose rates in rads/sec and krad/year.

Average dose rates are reported in rads/sec and krad/year. In addition, for the "worst-week" and "worst-day" solar particle environments, the event-integrated dose is also reported.

The output file contains a header which documents the inputs to the calculation. This header also reproduces the header information from the particle flux file which you input to DOSE.