title: Comparing standard Bonner spheres and high-sensitivity Bonner cylinders.
abstract: Standard Bonner spheres and proposed high-sensitivity Bonner cylinders were calibrated in a neutron calibration room, using a (252)Cf source. The Bonner sphere system consists of 11 polyethylene (PE) spheres of various diameters and 4 extended spheres that comprise embedded metal shells. Similar to the design of Bonner spheres, a set of Bonner cylinders was assembled using a large cylindrical (3)He tube as the central probe, which was wrapped using various thicknesses of PE. A layer of lead was employed inside one of the PE cylinders to increase the detection efficiency of high-energy neutrons. The central neutron probe used in the Bonner cylinders exhibited an efficiency of ∼17.9 times higher than that of the Bonner spheres. However, compared with the Bonner spheres, the Bonner cylinders are not fully symmetric in their geometry, exhibiting angular dependence in their responses to incoming neutrons. Using a series of calculations and measurements, this study presents a systematic comparison between Bonner spheres and cylinders in terms of their response functions, detection efficiencies, angular dependences and spectrum unfolding.
authors.affiliation: Institute of Nuclear Energy Research, Longtan, Taoyuan 32546, Taiwan, ROC Institute of Nuclear Engineering and Science, National Tsing Hua University, 101, Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC.
authors.forename: Kuo-Wei
authors.initials: KW
authors.lastname: Lee
authors.affiliation: Institute of Nuclear Energy Research, Longtan, Taoyuan 32546, Taiwan, ROC.
authors.forename: Ming-Chen
authors.initials: MC
authors.lastname: Yuan
authors.affiliation: Institute of Nuclear Engineering and Science, National Tsing Hua University, 101, Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC Department of Engineering and System Science, National Tsing Hua University, 101, Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC.
authors.forename: Shiang-Huei
authors.initials: SH
authors.lastname: Jiang
authors.affiliation: Institute of Nuclear Engineering and Science, National Tsing Hua University, 101, Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC Department of Engineering and System Science, National Tsing Hua University, 101, Sec. 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC rjsheu@mx.nthu.edu.tw.
authors.forename: Rong-Jiun
authors.initials: RJ
authors.lastname: Sheu
mesh_terms: D000465:Algorithms; D002138:Calibration; D002142:Californium; D004867:Equipment Design; D006371:Helium / Q000737:chemistry; D007554:Isotopes; D009502:Neutrons; D010315:Particle Accelerators; D020959:Polyethylene / Q000737:chemistry; D011829:Radiation Dosage; D011835:Radiation Protection; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods
chemical_list: D007554:Isotopes; D006371:Helium; D020959:Polyethylene; D002142:Californium