CURIE Measures Radiogenic Neutron Flux at 2.51e-5 cm-2 s-1 in Shallow Underground Site
The CURIE neutron background study provides quantitative radiogenic and cosmogenic fluxes critical for experiment design in shallow underground labs. Measurements exceed model predictions by 12% but align within errors, highlighting the value of empirical data over simulation alone for background budgeting.
Researchers deployed a Bonner Cylinder Spectrometer with a 3He counter and six HDPE moderators plus a BC-501A liquid scintillator at the Subatomic Particle Hideout in the Edgar Experimental Mine. The spectrometer response was simulated in GEANT4, calibrated with a 239Pu-9Be source using the shadow-cone method, and unfolded to extract the isotropic field flux after 1431 hours of scintillator data with pulse-shape discrimination isolating 55 neutron candidates. These values sit 12% above prior CURIE-specific Monte Carlo predictions yet remain consistent within combined uncertainties. The work supplies the first site-specific normalization for planning low-background experiments at 400 m.w.e. overburden.
Keblbeck et al.: CURIE muon-induced flux central value will fall within 15% of simulation when re-measured with 3000+ hours of scintillator data by 2028.
Sources (3)
- [1]Primary Source(https://arxiv.org/abs/2610.31856)
- [2]Supporting Source(https://arxiv.org/abs/1504.07980)
- [3]Supporting Source(https://doi.org/10.1016/j.nima.2018.10.045)