MSc Thesis Presentation: Developing The Detector Array for Energy Measurement of Neutrons (DAEMON)

MSc Candidate

Zarin Ahmed

Abstract

This work provides a detailed overview of the developmental progress and the current status of the DAEMON project, emphasizing both accomplished milestones and remaining tasks. Situated within the crucial field of research of nuclei far from the line of stable nuclei, the study delves into the increasing likelihood of \(\beta-delayed\) neutron \((\beta n)\) emission as one explores the neutron-rich region. Traditional \(\beta-decay \) studies relying solely on \(\gamma-ray\) detection fall short in unveiling detailed nuclear structure information on these exotic isotopes. Understanding neutron emission probabilities and neutron energy spectra becomes crucial, prompting the construction of a large-scale neutron detector like the Detector Array for Energy Measurements of Neutrons (DAEMON). DAEMON, currently in the design and testing phase, will employ the time-of-flight technique for high-resolution energy measurements of neutrons \(post-\beta n\) emission, in conjunction with DESCANT (an array of liquid scintillator detectors for high-efficiency neutron detection, but poor energy resolution) at the GRIFFIN decay station at the TRIUMF-ISAC radioactive beam facility. Findings from tests at the University of Guelph involving EJ200 plastic scintillator geometries, silicon photomultiplier (SiPM) arrays, and various DAQ considerations are presented. Experimental data, well-reproduced in simulations, highlights features introduced by software summing 2 × 2 SiPM arrays. Achieving low-energy detection thresholds as low as 13 keV with a width of 9 keV using \(\gamma-ray\) sources, coupled with a timing resolution of 406(20) ps FWHM using the 2 × 2 SiPM-scintillator setup and using a CAEN VX1730 digitizer DAQ system, meets the required resolution goals. This thesis outlines the project’s trajectory, marking upcoming tests for the significant transition to an ASIC-based DAQ system and prototype testing with monoenergetic neutron beam at the University of Kentucky Accelerator Laboratory.

Examination Committee

• Dr. Xiaorong Qin, Chair
• Dr: Paul Garrett, Advisor
• Dr. Liliana Caballero, Advisory Committee
• Dr. De-Tong Jiang, Graduate Faculty