Inputs

Inputs

All physics parameters are in one workbook, radcluster_code/input/input_parameters.xlsx.

Sheets

Sheet	Content
Production	survival efficiency, displacement and helium generation rates, clustered fractions, cascade power-law slopes and cut-offs. One column per spectrum (fission and fusion)
Energetics	lattice and elastic constants, atomic volume, formation energies, surface energy, loop Burgers vectors
Diffusion	pre-exponentials and migration energies for vacancies, SIAs and helium, 1D-glide parameters, solute concentrations and trap binding energies, mobility cut-offs
Dissociation	binding-energy models: void capillarity, helium virial equation of state, loop binding fits, trap-mutation barriers
Reactions	geometric prefactors, dislocation bias factors, sink densities, cluster-size limits, the discrete/bin split, solver settings

Rows

Each row contains:

• a parameter name
• a Symbol key
• a value
• the units
• a note that cites the equation or the table the value comes from

Overrides

The Symbol key is what a run-time override uses:

PARAM_OVERRIDES = {'T': 673.0, 'rho_d': 5e14, 'eta': 0.28}   # K, m^-2, -

An override replaces the workbook value for that run only. It is recorded in the provenance file of the run.

Note: Permanent changes belong in the workbook. The code reads the parameters. It does not hard-code them.

Cascade spectra

The fission and fusion spectra differ in the survival efficiency, the clustered fractions, the power-law slopes and the largest in-cascade cluster sizes. The cascade option of the simulation selects the column of the Production sheet, and with it the helium reduction (see Methodology).