Deuterated-xylene (xylene-d10; EJ301D): A new, improved deuterated liquid scintillator for neutron energy measurements without time-of-flight

Abstract

In conjunction with Eljen Technology, Inc. (Sweetwater,TX) we have designed, constructed, and evaluated a 3 in. x 3 in. deuteratedxylene organic liquid scintillator (C 8 D 10 ; EJ301D) as a fast neutron detector. Similar to deuterated benzene (C 6 D 6 ; NE230, BC537, and EJ315) this scintillator can provide good pulse-shape discrimination between neutrons and gamma rays, has good timing characteristics, and can provide a light spectrum with peaks corresponding to discrete neutron energy groups up to ca. 20 MeV. Unlike benzene-based detectors, deuterated xylene is less volatile, less toxic, is not known to be carcinogenic, has a higher flashpoint, and hence is much safer for many applications. In addition EJ301D can provide slightly more light output and better PSD than deuterated-benzene scintillators. We show that, as with deuterated-benzene scintillators, the

(d,n) proton-transfer reactions on Be9, B11<

“…In a recent experiment at E d =6 MeV evaluating an improved deuterated liquid scintillator (EJ301D), we obtained a 13 C(d,n) spectrum devoid of such spurious peaks and with somewhat better resolution [15]. The forward angle data closely resembles the data obtained in this experiment (Fig.4).…”

“…The proton separation energy for 13 N is S p = 1.943 MeV and thus the excited states in 13 N observed are proton unbound. This is important data as it demonstrates the spectroscopic capability of the UM-DSA array for the study of particle-unbound states, which will become more relevant in the transition to shows that this is due to recoil protons which leak into the deuteron PSD gate due to breakup of scintillator deuterons [10,11,[14][15][16]. The overall effect is small but can add to the systematic uncertainty of the measurements.…”

“…The effective energy resolution is often better than a typical n-ToF measurement using a modest flight-path for E n >10 MeV [23]. This is true if the deuterated scintillator data is devoid of most background and the PSD can separate the recoil deuterons cleanly over a range of energies [10,11,[14][15][16]. In many of the nuclei studied, this is still not sufficient to adequately resolve many of the individual excited states.…”

“…E d , max = (8/9)E n ]. Thus, a distinct peak in the scintillator light spectrum is generated with a peak location directly related to the incident neutron energy [7][8][9][10][11][12][13][14][15][16]. However the extraction of high-quality neutron energy spectra was limited in the past by the lack of accurate detector response data and the computing power needed to unfold the detector spectra.…”

“…In particular, neutron-gamma digital pulse-shape discrimination (PSD) has made it possible to develop improved algorithms for optimal particle identification in liquid scintillators. Also, many of the detector response functions needed for accurate spectral unfolding using DSP to produce good neutron energy spectra from deuterated scintillators are now available [14][15][16][17][18][19].…”