Publications Details

A search for cosmogenic production of β-neutron emitting radionuclides in water

Sweany, Melinda; Dazeley, S.; Askins, M.; Bergevin, M.; Bernstein, A.; Bowden, N.S.; Jaffke, P.; Rountree, S.D.; Shokair, T.M.

Here we present the first results of WATCHBOY, a water Cherenkov detector designed to measure the yield of β-neutron emitting radionuclides produced by cosmic ray muons in water. In addition to the β-neutron measurement, we also provide a first look at isolating single-β producing radionuclides following muon-induced hadronic showers as a check of the detection capabilities of WATCHBOY. The data taken over 207 live days indicates a 9Li production yield upper limit of 1.9× 10-7μ-1g-1 cm2 at ∼400 m water equivalent (m.w.e.) overburden at the 90% confidence level. In this work the 9Li signal in WATCHBOY was used as a proxy for the combined search for 9Li and 8He production. This result will provide a constraint on estimates of antineutrino-like backgrounds in future water-based antineutrino detectors.