Duvall Kenneth C, Meier Michael M, Wasson Oren A, Huynh Vinh D
Center for Radiation Research, National Bureau of Standards, Washington, DC 20234.
Bureau Internaltional des Poids et Mesures, Sevres, France.
J Res Natl Bur Stand (1977). 1978 Nov-Dec;83(6):555-561. doi: 10.6028/jres.083.037.
National Bureau of Standards (NBS) participation in an International Bureau of Weights and Measures (BIPM) sponsored neutron flux intercomparison is described. The efficiencies of two transfer instruments, a gas-filled He proportional counter and a BF counter imbedded in a polyethylene sphere, were determined at neutron energies of 250 keV and 560 keV. The efficiency of the He detector was determined by placing it in the flux monitored by the NBS "black" detector. Since the polyethylene sphere detector shadows the "black" detector, a secondary BF counter was calibrated and it normalized the sphere and "black" detector runs. The efficiencies are reported and compared to the quantities determined at other participating standards laboratories.
描述了美国国家标准局(NBS)参与国际计量局(BIPM)主办的中子通量比对的情况。在250 keV和560 keV的中子能量下,测定了两种传递仪器的效率,一种是充气氦正比计数器,另一种是嵌入聚乙烯球中的BF计数器。通过将氦探测器置于NBS“黑色”探测器监测的通量中来确定其效率。由于聚乙烯球探测器会遮挡“黑色”探测器,因此对一个辅助BF计数器进行了校准,并使其对球探测器和“黑色”探测器的测量结果进行归一化。报告了这些效率,并与其他参与的标准实验室所测定的量进行了比较。