ENTRY 14570 20200421 148814570 0 1 SUBENT 14570001 20200421 148814570 1 1 BIB 10 37 14570 1 2 TITLE Expansion of the surrogate method to measure the 14570 1 3 prompt fission neutron multiplicity for 241Pu 14570 1 4 AUTHOR (O.A.Akindele,B.S.Alan,J.T.Burke,R.J.Casperson, 14570 1 5 R.O.Hughes,J.D.Koglin,K.Kolos,E.B.Norman,S.Ota, 14570 1 6 A.Saastamoinen) 14570 1 7 INSTITUTE (1USAUCX,1USALRL,1USATAM) 14570 1 8 REFERENCE (J,PR/C,99,054601,2019) 14570 1 9 FACILITY (CYCLO,1USATAM) Experiment was performed at the Texas 14570 1 10 A&M University Cyclotron Institute 14570 1 11 SAMPLE (94-PU-238,ENR=0.00003) 14570 1 12 (94-PU-239,ENR=0.00005) 14570 1 13 (94-PU-240,ENR=0.00021) 14570 1 14 (94-PU-241,ENR=0.00006) 14570 1 15 (94-PU-242,ENR=0.99952) 14570 1 16 (94-PU-240,ENR=0.00021) 14570 1 17 (95-AM-241,ENR=0.00013) Target was made by 14570 1 18 electroplating of 242Pu onto 100 mu-g/cm2 thick 14570 1 19 natural carbon backing. Target thickness was 14570 1 20 140 mu-g/cm2. 14570 1 21 DETECTOR (TELES,SI,SI) Scattered alpha particles were detected 14570 1 22 using dE-E silicon telescope located downstream of the 14570 1 23 242Pu target. 14570 1 24 (SI) Another Si detector was located upstream of the 14570 1 25 target to identify fission events. 14570 1 26 (SCIN) A large cylindrical tank containing 2.2 tons 14570 1 27 of EJ-335 liquid scintillator was used to detect 14570 1 28 neutrons. Tank was segmented into four quadrants. 14570 1 29 Neutron detection efficiency was determined to be 14570 1 30 (50.81+-0.15)% 14570 1 31 METHOD Surrogate method was used. Reaction 14570 1 32 n + 241Pu -> 242Pu* -> FL + FH + nu*N 14570 1 33 was replaced by reaction 14570 1 34 a + 242Pu -> 242Pu* + a' -> FL + FH + nu*N 14570 1 35 (a' -> inelastically scattered alpha particle) 14570 1 36 assuming Bohr independence hypothesis 14570 1 37 ANALYSIS (SURGT) 14570 1 38 HISTORY (20200421C) Compiled by S.H. 14570 1 39 ENDBIB 37 0 14570 1 40 NOCOMMON 0 0 14570 1 41 ENDSUBENT 40 0 14570 199999 SUBENT 14570002 20200421 148814570 2 1 BIB 3 8 14570 2 2 REACTION (94-PU-241(N,F),,NU) 14570 2 3 Average neutron multiplicity for 241Pu(n,f) reaction 14570 2 4 ERR-ANALYS (ERR-T) Total uncertainties 14570 2 5 (ERR-1) Uncertainty in neutron detection efficiency 14570 2 6 (ERR-2) Additional systematic uncertainty due to energy14570 2 7 dependence of neutron detection efficiency 14570 2 8 STATUS (TABLE) Data presented in fig. 7 of the reference 14570 2 9 sent by author O.A.A. 14570 2 10 ENDBIB 8 0 14570 2 11 COMMON 3 3 14570 2 12 EN-ERR ERR-1 ERR-2 14570 2 13 MEV PER-CENT PER-CENT 14570 2 14 0.25 0.15 1. 14570 2 15 ENDCOMMON 3 0 14570 2 16 DATA 3 41 14570 2 17 EN DATA ERR-T 14570 2 18 MEV PRT/FIS PRT/FIS 14570 2 19 0.0 2.90 0.118 14570 2 20 0.5 2.92 0.094 14570 2 21 1.0 2.88 0.100 14570 2 22 1.5 3.17 0.112 14570 2 23 2.0 3.09 0.108 14570 2 24 2.5 3.16 0.111 14570 2 25 3.0 3.25 0.117 14570 2 26 3.5 3.37 0.124 14570 2 27 4.0 3.43 0.126 14570 2 28 4.5 3.49 0.128 14570 2 29 5.0 3.54 0.134 14570 2 30 5.5 3.72 0.142 14570 2 31 6.0 3.70 0.142 14570 2 32 6.5 3.85 0.146 14570 2 33 7.0 3.85 0.145 14570 2 34 7.5 4.17 0.149 14570 2 35 8.0 4.05 0.141 14570 2 36 8.5 4.05 0.142 14570 2 37 9.0 4.16 0.147 14570 2 38 9.5 4.19 0.150 14570 2 39 10.0 4.30 0.155 14570 2 40 10.5 4.26 0.155 14570 2 41 11.0 4.54 0.164 14570 2 42 11.5 4.46 0.166 14570 2 43 12.0 4.46 0.171 14570 2 44 12.5 4.51 0.174 14570 2 45 13.0 4.64 0.178 14570 2 46 13.5 4.70 0.180 14570 2 47 14.0 4.83 0.177 14570 2 48 14.5 4.85 0.182 14570 2 49 15.0 4.82 0.182 14570 2 50 15.5 5.05 0.183 14570 2 51 16.0 4.95 0.189 14570 2 52 16.5 5.00 0.184 14570 2 53 17.0 5.19 0.191 14570 2 54 17.5 5.18 0.194 14570 2 55 18.0 5.27 0.194 14570 2 56 18.5 5.06 0.191 14570 2 57 19.0 5.22 0.195 14570 2 58 19.5 5.39 0.199 14570 2 59 20.0 5.46 0.207 14570 2 60 ENDDATA 43 0 14570 2 61 ENDSUBENT 60 0 14570 299999 ENDENTRY 2 0 1457099999999