NIF ETA Experiment

The NIF energy tuning assembly (ETA) experiment was designed to spectrally shape the NIF deuterium-tritium fusion neutron source into a thermonuclear and prompt fission neutron spectrum. The environment was modeled in MCNP5 with a full-scale NIF model and neutron flux covariance with SCALE Sampler with MAVRIC. The neutron flux was unfolded using measured activation products and the initial guess spectrum with covariance information.
A highly enriched uranium sample was fielded in the experimental cavity of the ETA and fission products have been measured in the unique environment.

(MCNP directory) Contains an MCNP5 model for ETA experiment with a surface source SSR (rssa)

(SCALE Sampler and MAVRIC directory) Contains base input for SCALE MAVRIC with Sampler in 252 group structure with output lower triangular correlation matrix and neutron spectra related to experiment. The file outputs have been compressed into a Python pickle file which can be opened with: import pickle Datafiles=open('ETA_Fielded_Samples.pckl','rb') SampledData=pickle.load(Datafiles) Datafiles.close(). The file is a dictionary containing the response functions for each of the independent Sampler runs.

(PNNL STAYSL directory) Contains libraries, input, and output for STAYSL unfold in 129-group structure

(GEF directory) Contains General Observables of Fission code input and output for estimated fission products

(Fission Product Experimental Data directory) Contains experimental data utilized to fit to expression to estimate fission products

(Fission Products directory) Contains measured fission product data

(Components) Contains isotopic and elemental analysis of components.