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Neutrons – you either love them or you hate them.

The neutron is the neutral cousin of the electrically-charged proton in the atomic nucleus.   Without the strong binding of neutrons to protons, the nucleus would blow apart by the repulsive forces of the positively-charged protons.  Without the neutron, there would be no nuclei, no stable atoms, and no molecules.  The universe would be a very different place.  As a form of radiation, the neutron creates serious problems.  Without that electric charge, it ignores electric and magnetic fields.  This makes it difficult to stop and usually requires large amounts of lead and concrete.  Standard equipment like plastic scintillators or gaseous ion chambers are inefficient at detecting neutrons.  In experiments searching for dark matter, a dark matter particle is discovered when all other particles are accounted for.  Because of the neutron’s low detection efficiency, it is common for it to mimic the dark matter signal.

Dr. Michael Wood, a Physics Professor and chair of the Department of Quantitative Sciences, has been awarded a Department of Energy Small Business Innovation Research grant to test a novel material to efficiently detect neutrons.  The grant, titled “Gadolinium-Loaded Plastic Scintillators for Dark Matter Search”, is a $12,777.00 subcontract with Radiation Monitoring Devices, Inc. (RMD) in Watertown, MA and collaborators from Lamar University and Occidental College.  RMD will manufacture samples of a plastic scintillator loaded with gadolinium.  The gadolinium is special due to its ability to absorb neutrons and emit gamma rays that can be detected by the scintillator.   Dr. Wood will study the characteristics of the sample in his lab in Science Hall followed by a measurement of the detection efficiency with a dark matter detector at Occidental College in Los Angeles, CA.  If the gadolinium-loaded scintillators have a high detection efficiency, they will be utilized to remove the neutron background and eventually lead to a discover of a dark matter particle.

Submitted by: Dr. Michael Wood, Physics Professor and Chair, Department of Quantitative Sciences