ENTRY 41652 20180410 41804165200000001 SUBENT 41652001 20180410 41804165200100001 BIB 12 129 4165200100002 TITLE Fission of 232Th in a spallation neutron field 4165200100003 REFERENCE (J,PPN/L,13,244,2016) 4165200100004 (J,FCY/L,13,382,2016) Iss.2 Both in English 4165200100005 AUTHOR (V.I.Yurevich,V.A.Nikolaev,R.M.Yakovlev) 4165200100006 INSTITUTE (4ZZZDUB) V.I.Yurevich 4165200100007 (4RUSRI) V.A.Nikolaev,R.M.Yakovlev 4165200100008 FACILITY (SYNCH,4ZZZDUB) Synchrophasotron 4165200100009 REL-REF (I,,V.I.Yurevich+,J,FCY/L,3,(3),49,2006) Iss. 3/132 4165200100010 (I,,V.I.Yurevich+,J,PPN/L,3,169,2006) Engl.translation 4165200100011 Investigation of neutron emission in the interaction 4165200100012 of relativistic protons with lead target. 4165200100013 Neutron spectrum for 2.0 GeV protons. 4165200100014 INC-SOURCE (SPALL) Spallation in thick lead target 20cm diameter, 4165200100015 60cm thick. Burst of 9 sec with intensity 4165200100016 10**9 - 10**10 particles/burst . 4165200100017 Al-27(p,x)Na-24 and Al-27(d,x)Na-24 reactions were used4165200100018 to measure fluence of protons . 4165200100019 Energy of proptons - 0.99, 2.00, 3.65 GeV 4165200100020 INC-SPECT Neutron energy of spallation neutron spectrum - from 4165200100021 thermal to GeV. 4165200100022 Details of spectra for 2.0 GeV protons are given in 4165200100023 REL-REF of Yurevich+. 4165200100024 Neutron distributions over the side surface of lead 4165200100025 target as function of Z - distance from the target 4165200100026 center - are on Fig.1( proton energy 0.99 GeV), 4165200100027 Fig.2 (proton energy 3.65 GeV) for the minimal neutron 4165200100028 energies 0., 1., 6., 20., 100. GeV . 4165200100029 Data from REL-REF of V.I.Yurevich+ were used as initial4165200100030 approximation in the iteration method to obtain neutron4165200100031 energy distributions. 4165200100032 Neutron angular distributions are on Figs.3,4 as 4165200100033 function of minimal neutron energy at angles 10,30,60, 4165200100034 90,120,150deg ( units n/sr/p ) . 4165200100035 Angular distributions for 5 energy groups 4165200100036 (digitized data) 4165200100037 - for proton energy 0.99 GeV ( Fig.3 ) : 4165200100038 Min.neutron energy,MeV Angle,degree dF/dAngle,n/sr/p 4165200100039 100. 10. 0.018461 4165200100040 20. 10. 0.14381 4165200100041 6. 10. 0.21618 4165200100042 1. 10. 0.60223 4165200100043 0. 10. 1.2173 4165200100044 100. 30. 0.17600 4165200100045 20. 30. 0.30557 4165200100046 6. 30. 0.36941 4165200100047 1. 30. 0.82311 4165200100048 0. 30. 1.5211 4165200100049 100. 60. 0.077729 4165200100050 20. 60. 0.20510 4165200100051 6. 60. 0.33114 4165200100052 1. 60. 1.1701 4165200100053 0. 60. 1.8015 4165200100054 100. 90. 0.04489 4165200100055 20. 90. 0.1689 4165200100056 6. 90. 0.3023 4165200100057 1. 90. 1.283 4165200100058 0. 90. 2.077 4165200100059 100. 120. 0.024657 4165200100060 20. 120. 0.14720 4165200100061 6. 120. 0.29486 4165200100062 1. 120. 1.4058 4165200100063 0. 120. 2.2041 4165200100064 100. 150. 0.023999 4165200100065 20. 150. 0.12119 4165200100066 6. 150. 0.24301 4165200100067 1. 150. 1.2149 4165200100068 0. 150. 1.9593 4165200100069 - for proton energy 3.65 GeV ( Fig.4 ) : 4165200100070 Min.neutron energy,MeV Angle,degree dF/dAngle,n/sr/p 4165200100071 100. 10. 1.1172 4165200100072 20. 10. 1.3155 4165200100073 6. 10. 1.5491 4165200100074 1. 10. 2.7254 4165200100075 0. 10. 4.0723 4165200100076 100. 30. 0.68427 4165200100077 20. 30. 1.0857 4165200100078 6. 30. 1.3832 4165200100079 1. 30. 3.2828 4165200100080 0. 30. 5.1338 4165200100081 100. 60. 0.26276 4165200100082 20. 60. 0.75260 4165200100083 6. 60. 1.2519 4165200100084 1. 60. 3.9584 4165200100085 0. 60. 5.8628 4165200100086 100. 90. 0.13535 4165200100087 20. 90. 0.59162 4165200100088 6. 90. 1.1421 4165200100089 1. 90. 4.5187 4165200100090 0. 90. 7.0058 4165200100091 100. 120. 0.077282 4165200100092 20. 120. 0.45931 4165200100093 6. 120. 0.92146 4165200100094 1. 120. 4.5519 4165200100095 0. 120. 7.8347 4165200100096 100. 150. 0.030170 4165200100097 20. 150. 0.49283 4165200100098 6. 150. 0.81303 4165200100099 1. 150. 3.4405 4165200100100 0. 150. 5.7329 4165200100101 In Table 8 of REL-REF of Yurevich+ 4165200100102 average neutron energy , 4165200100103 neutron kinetic energy Ekin 4165200100104 for incident P and D are given for Pb of 4165200100105 diameter 20 cm x 60 cm. 4165200100106 Proton energy, GeV ,MeV Ekin,MeV 4165200100107 0.994 8.82 213. 4165200100108 2.0 11.6 513. 4165200100109 3.65 13.7 1106. 4165200100110 DETECTOR (THRES) Fission threshod detectors with 1mg/cm2 layers 4165200100111 of U-235, Np-237, U-238, Bi-209. 4165200100112 6-mum PETP SSNTD to detect fragments produced . 4165200100113 Threshold detector Responces 4165200100114 90% 60% 4165200100115 U-235(n,f) 0.16-35.4 MeV 0.47-4.30 MeV 4165200100116 Np-237(n,f) 0.58-39.3 MeV 0.98-5.31 MeV 4165200100117 U-238(n,f) 1.50-113. MeV 2.06-25.8 MeV 4165200100118 Th-232(n,f) 1.50-155. MeV 2.54-48.5 MeV 4165200100119 Bi-209(n,f) 66.5-443. MeV 101.-291. MeV 4165200100120 SAMPLE 1 g/cm2 Th layer over the side surface of target per 4165200100121 proton. 4165200100122 CORRECTION Background was measured at 1m from the target center 4165200100123 to be (7+-2) % . 4165200100124 HISTORY (20160622C) M.M. Request for the data was sent to 4165200100125 V.I.Yurevich - no reply . 4165200100126 Subent 002 was deleted from final trans according to 4165200100127 a comments of N.Otsuka (NDS,IAEA) - 4165200100128 spectrum average CS for Eproton=0.99, 2.0, 3.65 GeV, 4165200100129 neutron mean energy 8.82, 11.6, 13.7 MeV - 4165200100130 121+-19, 123+-16, 124+-17 mb, respectively. 4165200100131 ENDBIB 129 0 4165200100132 NOCOMMON 0 0 4165200100133 ENDSUBENT 132 0 4165200199999 ENDENTRY 1 0 4165299999999