A package for calculating neutron properties from DT and DD fusion reactions.

This package accurately calculates the neutron energies and distributions by accounting for the plasma temperature.

• mean neutron energy
• neutron energy standard deviation
• thermal reactivity

A Python 🐍 package with a Rust 🦀 backend.

The package makes use of the Sadler–Van Belle formula and Bosch-Hale parametrization for reactivity. For energy distributions Ballabio is used.

This package has been inspired by the NeSST package.

Install

pip install fusion_neutron_utils

Usage

To find the average neutron energy and the standard deviation of that energy.

These results could then be input into openmc.stats.Normal distribution for a neutron source term in OpenMC

from fusion_neutron_utils import neutron_energy_mean_and_std_dev
neutron_energy_mean_and_std_dev(
    reaction='D+T=n+a',
    ion_temperature=30e3,
    temperature_units='eV',
    neutron_energy_units='eV'
)
>>>>(14092196.942384735, 413861.375751198)

The relative reaction rates can be found for the different reactions, this can be useful for setting the relative Source.strength in OpenMC. Relative reaction rates returns the DT, DD (n+He3), and DD (p+T) reaction rates in that order. Note the DD (p+T) does not emit a neutron but is there for completeness.

from fusion_neutron_utils import relative_reaction_rates
relative_reaction_rates(
    ion_temperature=30e3,
    temperature_units='eV',
    dt_fraction=0.1,
    dd_fraction=0.9,  
)
>>>[0.9989900631769298, 0.0005595866500573114, 0.00045035017301275736] 

The reactivity can also be found, this can be useful for finding the relative reaction rate for D+D or D+T at a specific temperature

from fusion_neutron_utils import reactivity
reactivity(
    ion_temperature=30e3,
    temperature_units='eV',
    reactivity_units='m^3/s',
    reaction='D+D=p+T',
    equation='Bosch-Hale'
)
>>>2.2356373732343755e-53