MRI: Equipment: A New CeBr3 Gamma-Ray Detection Array (CeBrA) for Particle-Gamma Coincidence Experiments at the FSU Super-Enge Split-Pole Spectrograph

This award provides support for Ursinus College, a primarily undergraduate institution, to upgrade the particle-gamma ray coincidence capabilities at the John D. Fox Laboratory at Florida State University (FSU) by expanding the existing array of low-background CeBr3 scintillation detectors used to measure gamma rays in coincidence with particles collected by Super-Enge Split-Pole Spectrograph (SE-SPS) following nuclear reactions.

This combined setup will enable selective and detailed studies of nuclear-structure phenomena, of which many are also relevant for understanding nuclear reactions taking place in explosive stellar environments. The development of this array, known as CeBrA, will be performed by the PI and undergraduate students at Ursinus College in collaboration with co-PIs from Florida State University (FSU) and Ohio University (OU).

This new instrument will be a significant upgrade of present particle-gamma coincidence capabilities at FSU, will enable access to low-energy nuclear science facilities, and contribute to the education and training of the next generation of nuclear scientists. Those involved in this project will gain skills in using radiation detectors, troubleshooting, gathering, and analyzing data, and preparing results for publication.

The funds from this Major Research Instrumentation (MRI) grant will create an instrument for the measurement of gamma-rays in coincidence with charged particles detected in the SE-SPS. The planned CeBrA will consist of 14 low-background CeBr3 scintillation detectors with Hamamatsu photomultipliers read out with CAEN digitizers. The energy resolution of the CeBr3 detectors is sufficient to disentangle g decays leading to different excited states, enabling experimental programs complimentary to those at rare isotope facilities such as the Facility for Rare Isotope Beams at Michigan State University.

The initial testing and characterization of the CeBr3 detectors will be performed at Ursinus College. This stage will provide a unique possibility for the undergraduate students to get exposed to modern g-ray spectroscopy techniques and instruments at their home institution. At the same time, a GEANT4 simulation of the different detectors will be developed at Ursinus with support from FSU and OU.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.