2007/12/12 by Richard H. Olsher, R. H. Olsher, David T. Seagraves +1
Engineering · Physics and Astronomy · #Atomic and Subatomic Physics Research #Computer science #Electrical engineering #Engineering #Environmental science #Metre #Neutron #Nuclear Physics and Applications #Nuclear engineering #Nuclear physics #Physics #Radiation Detection and Scintillator Technologies #Upgrade
paper · doi:10.1097/01.hp.0000284890.33001.af
openalex publication_date 2007/12/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Thermo Fisher Scientific's NRD rem meter has been in production for almost 40 y and is the primary rem meter in use at many U.S. Department of Energy facilities. An upgrade project was initiated at the Los Alamos National Laboratory with the primary goal of increasing the NRD's neutron sensitivity through the substitution of pressurized 3He gas (4 atmospheres) for the stock counter tube's BF3 fill gas. Historically, BF3 counters were far less expensive relative to 3He and were usually chosen on the basis of cost. That is no longer the case, with pricing for both types of counters being similar. Test results have shown that the 3He counter version of the NRD exhibits stable operation at a reasonable bias voltage and good gamma rejection. Sensitivity has been increased by about a factor of four with no penalty in cost.