ENTRY 23710 20200520 228823710 0 1 SUBENT 23710001 20200505 228823710 1 1 BIB 12 25 23710 1 2 TITLE The mass-yield curve for fission of 237Np by 14.5 MeV 23710 1 3 neutrons 23710 1 4 AUTHOR (R.F.Coleman,B.E.Hawker,J.L.Perkin) 23710 1 5 REFERENCE (J,JIN,14,8,1960) 23710 1 6 INSTITUTE (2UK ALD) 23710 1 7 FACILITY 500 keV deuterons bombard zirconium-tritide target. 23710 1 8 INC-SOURCE (D-T) 23710 1 9 INC-SPECT . 5.E+9 /sec/cm2 to measure various fission yields 23710 1 10 relative to Mo-99 yield. 23710 1 11 . Smaller neutron flux to measure absolute yield of 23710 1 12 Mo-99. 23710 1 13 .Neutron flux was determined by counting associated 23710 1 14 alpha-particles from D-T reaction. 23710 1 15 Thermal and epithermal neutrons < 3.E-5 % of 14 MeV 23710 1 16 flux, 1-3 MeV neutrons ~1% of 14 MeV flux. 23710 1 17 SAMPLE 200 mg of pure Np dioxide in the form of discs of 23710 1 18 100 mg/cm2 thickness between Al-catcher foils. 23710 1 19 DETECTOR (PROPC) . Placed at 135 deg to deuteron beam - to count23710 1 20 alpha-particles for the flux measurement. 23710 1 21 . 4PI proportional counter for fission products. 23710 1 22 METHOD (CHSEP) Details are given in the article. 23710 1 23 REL-REF (N,,D.Strominger+,J,RMP,30,585,1958) 23710 1 24 (N,,S.Katcoff,J,NUC,16,(4),78,1958) 23710 1 25 Two refs. for decay schemes and branching ratios. 23710 1 26 HISTORY (20200520C) M.M. 23710 1 27 ENDBIB 25 0 23710 1 28 COMMON 1 3 23710 1 29 EN 23710 1 30 MEV 23710 1 31 14.5 23710 1 32 ENDCOMMON 3 0 23710 1 33 ENDSUBENT 32 0 23710 199999 SUBENT 23710002 20200520 228823710 2 1 BIB 7 11 23710 2 2 REACTION (93-NP-237(N,F)ELEM/MASS,CUM,FY) 23710 2 3 MONITOR (93-NP-237(N,F)42-MO-99,CUM,FY) 23710 2 4 MONIT-REF (23710003,R.F.Coleman+,J,JIN,14,8,1960) 23710 2 5 Measured in this additional experiment, see Subent 003.23710 2 6 ANALYSIS Each value is the mean of three independent 23710 2 7 determinations from different irradiations. 23710 2 8 CORRECTION For Cd-115 - 10% correction to take into account 23710 2 9 the yield of Cd-115m. 23710 2 10 ERR-ANALYS (DATA-ERR) Total spread of individual result. 23710 2 11 STATUS (TABLE) Table 3 of 23710 2 12 J.of Inorganic and Nuclear Chemistry,14,8,1960 23710 2 13 ENDBIB 11 0 23710 2 14 COMMON 1 3 23710 2 15 MONIT 23710 2 16 PC/FIS 23710 2 17 4.94 23710 2 18 ENDCOMMON 3 0 23710 2 19 DATA 4 18 23710 2 20 ELEMENT MASS DATA DATA-ERR 23710 2 21 NO-DIM NO-DIM PC/FIS PC/FIS 23710 2 22 38. 91. 2.71 0.25 23710 2 23 39. 93. 4.94 0.25 23710 2 24 40. 97. 5.43 0.49 23710 2 25 45. 105. 3.50 0.20 23710 2 26 46. 109. 1.48 0.25 23710 2 27 46. 112. 1.23 0.05 23710 2 28 47. 111. 1.23 0.05 23710 2 29 48. 115. 1.23 0.05 23710 2 30 51. 127. 2.52 0.15 23710 2 31 52. 132. 4.29 0.74 23710 2 32 53. 131. 3.55 0.59 23710 2 33 56. 139. 4.84 0.35 23710 2 34 56. 140. 4.89 0.35 23710 2 35 58. 143. 3.60 0.74 23710 2 36 60. 147. 1.73 0.25 23710 2 37 62. 153. 0.32 0.025 23710 2 38 63. 157. 0.094 0.030 23710 2 39 64. 159. 0.069 0.030 23710 2 40 ENDDATA 20 0 23710 2 41 ENDSUBENT 40 0 23710 299999 SUBENT 23710003 20200520 228823710 3 1 BIB 6 20 23710 3 2 REACTION (93-NP-237(N,F)42-MO-99,CUM,FY) 23710 3 3 FLAG (1.) Measured by absolute neutron flux determination. 23710 3 4 (2.) Measured by mass yield curve determination. 23710 3 5 (3.) Mean of two measured values. 23710 3 6 METHOD 1. Irradiation at known neutron flux. Np-237 fission 23710 3 7 cross section used was base on two values 23710 3 8 2.4+-0.2 b for 14.6 MeV of Protopopov+ and 23710 3 9 2.5+-0.07 b for 14.0 MeV of Moat; 23710 3 10 More precise value at slightly lower energy was used. 23710 3 11 2. Relative mass yield curve was normalized to 200 %. 23710 3 12 Mirror points were calculated on the base of 23710 3 13 NU ~4.5 n/fis to draw smooth curve. 23710 3 14 REL-REF (R,40390003,A.N.Protopopov+,J,AE,4,190,1958) 23710 3 15 A.Moat, to be published in J.Nucl.Energy. 23710 3 16 ERR-ANALYS (DATA-ERR) Type of uncertainty is not explained in the 23710 3 17 article. It's mentioned only, that for value with 23710 3 18 Flag 1. the error includes error of fission cross 23710 3 19 section. 23710 3 20 STATUS (TABLE) Text page 13 of 23710 3 21 J.of Inorganic and Nuclear Chemistry,14,8,1960 23710 3 22 ENDBIB 20 0 23710 3 23 COMMON 1 3 23710 3 24 MONIT 23710 3 25 PC/FIS 23710 3 26 4.94 23710 3 27 ENDCOMMON 3 0 23710 3 28 DATA 3 3 23710 3 29 DATA DATA-ERR FLAG 23710 3 30 PC/FIS PC/FIS NO-DIM 23710 3 31 4.97 0.2 1. 23710 3 32 4.90 0.2 2. 23710 3 33 4.94 0.2 23710 3 34 ENDDATA 5 0 23710 3 35 ENDSUBENT 34 0 23710 399999 ENDENTRY 3 0 2371099999999