Analysis of (n, γ) Reactions in Natural Gadolinium by Thermal Neutron Beam

Gadolinium is an element of significant interest in several applications, such as radiotherapy and experimental neutrino physics, due to the large neutron capture cross section of its isotopes ¹⁵⁵Gd and ¹⁵⁷Gd. We present results from measurements of neutron capture conducted at the University of Massachusetts Lowell Research Reactor where a sample of natural gadolinium metal is incident to a beam of neutrons from the reactor thermal column. An array of high-purity germanium (HPGe) detectors were positioned about the target to collect gamma spectra for evaluation against ENSDF reference data. This proof-of-concept experiment is the early stage of a series of planned measurements with the reactor thermal column; we discuss new developments to the detector array, including a customized amplifier stage for Transistor Reset pulses from the preamplifiers of newly acquired HPGe detectors, the addition of purpose-built CdZnTe (CZT) detectors for X-ray emissions, and a remote-operated sample positioning system to be used in upcoming trials with gadolinium and other targets of interest.