Prof. Dr. Patrick Regan (U Surrey): The Application of LaBr3(Ce) Gamma-ray Detectors for Precision Nuclear Structure Spectroscopy Studies and Absolute Measurement Standards
An overview of the recent exploitation of discrete-energy gamma-ray detectors based on cerium-doped Lanthanum-tribromide (LaBr3) halide scintillators will be presented, including a review of the nuclear gamma-ray fast-timing technique, instrumentation, signal processing and coincidence analysis methods. Examples of research focussed on nuclear collective excitations in competition with single-particle-like transitions will be discussed, including experiments carried out using with hybrid HPGe-LaBr3 gamma-ray coincidence arrays for in-beam nuclear spectroscopy measurements, at ROSPHERE at IFIN-HH, Romania and nuBALL at IPN-Orsay, France. The LaBr3 array, FATIMA has been designed for radioactive decay and isomer studies at intermediate-energy projectile fragmentation Radioactive Beam facilities, with initial results from such experiments demonstrated following beta-decay studies of fission fragments in conjunction with the EURICA decay gamma-ray at the RIBF-RIKEN, Japan. The first commissioned, full experiment using the FATIMA array within the Decay Spectroscopy (DESPEC) set-up at GSI took place in March 2020; preliminary results of its operation will be presented. If time allows, applications of the LaBr3 detectors for measurements of absolute nuclear reaction ‘sub-barrier’ fusion cross-sections of nucleosynthesis interest and absolute radioactive material standardisation at the UK’s National Measurement Institute, NPL, will be presented, highlighting some of the unique sub-nanosecond timing capabilities and limitations of using these medium energy resolution detectors.