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1 Contents Overview of Neutron Beam facilities of HANARO Cold Neutron Guide Project Thermal Neutron Guide Project 2 HANARO Reactor Hall ENF PGAA RSI NRF HRPD T-TAS Bio-C Bio-D FCD 3 •14 in operation 7 thermal: HRPD, FCD, RSI, NRF, ENF, PGAA , Bio-D 7 cold: 18M & 40M SANS, REF-V, DC-ToF, Bio-REF, G-TS , KIST-USANS •5 under commissioning Th-TAS, Bio-C , Cold-TAS, C-PGAA, C-NDP DS-TOF 18M-SANS 40M-SANS Bio-REF USANS C-TAS RDF-V G-TS 4 Overview of CNRF Project at HANARO Project : Establishment of infrastructure for cold neutron research facilities at HANARO Project start : July. 2003 Project end : May. 2010 (start of normal operation) Project objectives : Development of a cold neutron source Development of a neutron guide system Development of five new spectrometers 40-m SANS, Cold-TAS, DC-TOF, HR-SANS, Guide Test Station Re-location of three (3) spectrometers existing in the reactor hall REF-V Bio-REF 6m-SANS 18m-SANS 5 Cold Neutron Guide system 5 neutron guide(M=2) with different cross-section installed in the beam plug starting at position with a distance of 1.84m from the cold source. After the beam plug filled with helium, the main rotary shutter located outside the biological shielding operating with vacuum. After the main shutter, the guides start to curve, in order to remove the gamma rays and fast neutrons having different curvatures. Two of the guides seperated into 2 guides. (total 7 cold neutron guides) The layout of the beam plug guides 6 Cold neutron guide (detail) Guide tubes at the reactor wall (to guide shielding room) In-pile Plug Removable Shielding Guide Guide tube in the beam tube at the entrance position from the cold source of 1.83m Primary Shutter Guide Support Fig 4. Neutron Guide System 7 Cold Neutron Instruments • • Five new neutron scattering instruments had developed and installed in the cold neutron guide hall, and three neutron instruments were moved from reactor hall to guide hall. The layout of the instruments in the cold neutron guide hall had been determined throughout simulations to optimize the performance of each instruments. Guide (dimension) CG1 (20x150mm) CG2 (50x150mm) CG5 (50x150mm) Curvature Length of curved part Line of sight +3.04 400m↗ 26m 8m 800m↗ 24m 17.9m (40M-SANS) 350m↗ 26.3m 11.8m (Cold-PGA) 2500m↗ 25.6m 24.5m (DC-TOF) 2500m↗ 32m 36.8m *** 600m↘ 16m 15.5m (Hr-SANS) (Bio-REF) (18M-SANS) 1500m↘ 26m 31.4m (Cold-TAS) CG2A (50 x 50mm) CG2B (50 x 95mm) CG3 (30x150mm) CG4 (50x150mm) incline angle CG4A (50x50mm) CG5A (50x150mm) (Mirror-Test) (V-REF) (NDP) +2.03 +0.54 CG4B (50x95mm) Instrument -0.93 -2.50 8 Layout of cold neutron instruments 9 Guide Hall 10 Tracing Neutron Guide Performance Cold neutron guide and cold source performance have been traced at each cold neutron instruments with measuring neutron flux. Measured neutron intensity with a standard sample (silica) at 40M SANS 11 Neutron guide fabrication Sputtering : magnetron sputtering system (4 magnetron guns + ion gun) Neutron guide of KAERI : M2 Supermirror, Reflectivity : 88% at critical angle 12 Thermal Neutron Guide Project 2014 : Planning project milestone 2015~2016 : Preliminary conceptual design of ST1 beam plug, main shutter and neutron guide shielding, High-M neutron guide development 2016 :Thermal neutron guide project proposal 2017 : Project start 2020 : Project end Project objectives : Development of a thermal neutron guide system including neutron guide production Development of four new spectrometers I-RSI, I-HRPD, T-NR, Raue diffractometer Re-location of three (3) spectrometers existing in the reactor hall Bio-C/D, RSI 13 Neutron flux at beam port noses Beam tube Thermal neutron flux < 0.625eV ST1 1.89 x 1014 ST2 2.22 x 1014 ST3 2.24 x 1014 ST4 2.53 x 1014 CN 9.68 x 1013 NR 4.32 x 1013 IR 2.70 x 1014 14 Thermal guide (beam port ST1) 15 Reactor hall and guide hall comm Cold guide hall Reactor hall NR In op RSI, ENF T-TAS Thermal Guide Bio-C, D HRPD, FCD Cold TAS KIST-USANS Bio-REF 18M SANS GT-S REF-V CONAS Length from beam nose to reactor wall : 14.47m Length from reactor wallbuilding to thermal guide shielding wall : 30.3m Aux Length from beam nose to main shutter end : 5.7m Total length form beam nose to thermal guide shielding wall : 44.47 Available total length for the curved guide : 38.77 Length of line of sight for a neutron guide with a width of 50mm Curvature 1500m 31.4m Curvature 2000m 33.8m 40M SANS DC-TOF Thermal neutron guide Some information for simulation - Beam nose : f 88mm - Neutron guide starting position : 1.78m from beam nose - Neutron guides : 3 guides (50mmW x 150mmH) - Neutron guide curvature :1500m - Neutron flux at beam nose : 1.89x10 14 𝑛/𝑐𝑚 2 ∙ 𝑠𝑒𝑐 - Length of the 1st straight part of the neutron guide 3.94m - Length of the curved neutron guide after the main shutter : 32m - Length of the 2nd straight part of the neutron guide : 30m 17 Thermal guide Neutron flux calculation McSTAS(ver.2.1) Measurement At main shutter position Neutron flux Neutron flux Neutron flux Neutron flux At curved guide end At straight guide end M=2 (SM for plug&main M=2 (SM for curved M=2 (SM for straight shutter guide) guide) guide) 3.45E10 n∙cm 2 ∙sec 4.92E9 n∙cm 2 ∙sec 4.28E9 n∙cm 2 ∙sec M=2 M=3 M=2 3.45E10 n∙cm 2 ∙sec 1.04E10 n∙cm 2 ∙sec 6.48E9 n∙cm 2 ∙sec M=2 M=3 M=3 3.45E10 n∙cm 2 ∙sec 1.04E10 n∙cm 2 ∙sec 8.16E9 n∙cm 2 ∙sec M=3 M=3 M=3 4.18E10 n∙cm 2 ∙sec 1.18E10 n∙cm 2 ∙sec 8.81E9 n∙cm 2 ∙sec 18 Simulation result (M3M3M3) 19 Simulation result Maxwell distributions of thermal neutrons at straight guide end position 20 Simulation result (M2M3M3) 21 Layout of thermal neutron guides Cold neutron guide Thermal neutron guide Thermal neutron instrument 22 Summary Six cold neutron guides were successfully installed and stabilized. Seven cold neutron instruments are operating and open to domestic and international users. Three instruments are under commissioning will and open next year. A proposal for development of thermal neutron guides and thermal neutron instruments will be submitted late 2016, and the project will start in 2017. 23 Thank you for your attention!! 24
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