Program - Brookhaven National Laboratory

presentation. The detector energy scale was calibrated with standard gamma-rays sources, in the electron
energy range 0.3 MeVee to 4 MeVee 207 Bi, and 252 Cf sources, and background were measured during
long duration experiments. The PH distributions for measurements at the end of each run were compared
with the reference spectra. The gain correction was estimated by using the Least Squares Method with
a non-linear fitting procedure. Our results demonstrate a rather large non-linearity of the scale and the
importance of the off-line gain corrections.
Corresponding author: Thomas N. Massey
PR 29
Fast Neutron Spectroscopy with Cs2LiYCl6
N. D’Olympia, P. Chowdhury, C.J. Guess, T. Harrington, E.G. Jackson, S. Lakshmi, C.J. Lister,
Department of Physics and Applied Physics, University of Massachusetts, Lowell, Lowell MA 01854. J.
Glodo, R. Hawrami, K. Shah, U. Shirwadkar, Radiation Monitoring Devices Inc., Watertown, MA 02472.
Neutron spectroscopy has re-emerged as a key area of research in nucleosynthesis science and nuclear
structure, while having always been important in many applied nuclear fields, such as reactor control,
fusion science, and homeland security. Technically, efficient, high resolution neutron spectroscopy has
always been challenging, and so new technologies are constantly being sought. Cs2LiYCl6 (CLYC) has
recently attracted interest as a thermal neutron detector due to its excellent neutron / gamma-ray pulseshape
discrimination and good energy resolution for both gamma-rays and neutrons. Preliminary work
using a 1”x1” CLYC detector has yielded intriguing results for the possibility of employing CLYC for
fast neutron spectroscopy. The response of this detector to mono-energetic neutrons was studied at the
University of Massachusetts Lowell 5.5 MV Van de Graaf using neutrons with energies spanning range of
0.8 MeV to 2.0 MeV, produced via the 7 Li(p,n) reaction. In the fast neutron response, a broad continuum
from the 6 Li(n,α) reaction was observed, and also a peak arising from the 35 Cl(n,p) 35 S reaction, which
had not previously been reported. This latter reaction, with a positive Q-value of 615keV, yields a single
neutron-induced peak with a resolution of 9%, determined by the reaction kinematics, making CLYC
a promising candidate as a fast neutron spectrometer in the energy range of 0.5 to 3 MeV. Simulations
using MCNPX corroborate our initial findings and allow us to investigate methods by which the practical
measurement range can be extended to at least 10 MeV. New results will be presented, covering neutrongamma
separation, energy resolution for gamma rays and neutrons, efficiency, and timing. This research
was supported by grants from DOE Office of Science, NNSA, and the SBIR program.
Corresponding author: C.J. (Kim) Lister
PR 30
X-Ray Fluorescence to Determine Zn in Bolivian Children Using Hair Samples
C.A. Telleria Narvaez, S. Fernandez Alcazar, F.G. Barrientos Zamora, A.O. Munoz Gosalvez, Centro de
Investigaciones y Aplicaciones Nucleares (CIAN-Viacha). Viacha, Bolivia. L.E. Romero Bolanos,
Instituto Boliviano de Ciencia y Tecnologia Nuclear. Av. 6 de Agosto No 2905. La Paz, Bolivia. G.M.
Ramirez Avila, Instituto de Investigaciones Fisicas, Universidad Mayor de San Andres. Campus
Universitario Cota Cota. Casilla 8635. La Paz, Bolivia.
With the aim of evaluating nutritional levels in Bolivian children (8-13 years-old), we carried out X-Ray
Fluorescence measurements in hair samples of children belonging to different social classes and living either
in rural areas or in cities. The aim of this study is to contribute to health policies tending to improve
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