Neutron Spectroscopy without Time-of-Flight: Spectrum Unfolding and (d,n) Measurements with Deuterated Liquid Scintillators

Deuterated liquid scintillation detectors can provide neutron spectroscopic information without time-of-flight (ToF) [1] allowing for close proximity to the reaction chamber for large angular coverage and increased absolute detector efficiency. This has led to the development of the University of Michigan Deuterated Scintillator Array (UM-DSA) and its associated high-speed digital-signal processing system [1]. As part of the UM project, the response matrix for the deuterated scintillator (EJ-315) utilized in the UM-DSA was measured using a ToF slicing method with neutrons up to 30 MeV produced from the reaction of 15 MeV deuterons on a thick 11B target. A Maximum Likelihood Expectation Maximization (MLEM) method was used for extraction of data for excited states populated in 9Be, 11B, 13C, 14,15N, and 19F(d,n) reactions performed at Ed $=$ 16.0 MeV. Cross sections from 10 to 160 deg. (lab) permitted assignment of angular momentum transfers and extraction of spectroscopic information using a DWBA analysis. Other applications of these detectors will also be discussed. \\[4pt] [1] M. Febbraro, et al., IEEE TNS 60 (2013) 890 - 896.