Optimizing the 8 Li yield for the IsoDAR Neutrino Experiment

Abstract

© 2019 IOP Publishing Ltd and Sissa Medialab. The focus of this paper is on optimizing the electron-antineutrino source for the IsoDAR (Isotope Decay at Rest) experimental program. IsoDAR will perform sensitive short-baseline neutrino oscillation and electroweak measurements, among other Beyond Standard Model searches, in combination with KamLAND and/or other suitable detectors. IsoDAR will rely on the high-Q β- decay of the 8Li isotope for producing electron-antineutrinos, created mainly via neutron capture in an isotopically enriched 7Li sleeve surrounding the Be target. In particular, this paper examines the performance, defined in terms of absolute 8Li (or, equivalently, electron-antineutrino) production rate, of various candidate sleeve materials, including a lithium-fluoride, beryllium-fluoride mixture ("FLiBe") sleeve and a homogeneous mixture of lithium and beryllium ("Li-Be"). These studies show that the 8Li yield can be increased substantially by employing a Li-Be sleeve and therefore motivate significant changes to the nominal IsoDAR design.