ENTRY 21568 20230212 231421568 0 1 SUBENT 21568001 20230212 231421568 1 1 BIB 12 82 21568 1 2 TITLE Measurement of the U-235(n,2n) cross section between 21568 1 3 threshold and 13 MeV 21568 1 4 AUTHOR (J.Frehaut, A.Bertin, R.Bois) 21568 1 5 REFERENCE (J,NSE,74,29,1980) For experimental information and 21568 1 6 U-235 data. 21568 1 7 (W,FREHAUT,19800609) Letter of J.Frehaut. 21568 1 8 (R,CEA-R-6447,2016) Revised data 21568 1 9 INSTITUTE (2FR BRC) Service De Physique Neutronique Et 21568 1 10 Nucleaire. 21568 1 11 REL-REF (M,,J.Frehaut,J,NIM,135,511,1976) 21568 1 12 Ref. for setup, method, corrections details. 21568 1 13 (O,21971004,J.Frehaut,R,CEA-R-6447,201611) 21568 1 14 H-2 n,2n cross section 21568 1 15 (O,21669001,J.Frehaut,R,CEA-R-6447,201611) 21568 1 16 C-13 n,2n cross section 21568 1 17 (O,20416001,J.Frehaut,R,CEA-R-6447,201611) 21568 1 18 Lot of other n,2n cross-sections . 21568 1 19 FACILITY (VDGT,2FR BRC) 14 MeV Tandem Van de Graaff, 21568 1 20 2.5 MHz, pulse width ~2 ns. 21568 1 21 DETECTOR (STANK) Large Gd-loaded liquid scintillator. 21568 1 22 Detector efficiency determined relative to the 21568 1 23 average number of prompt neutrons per spontaneous 21568 1 24 fission of Cf-252, taken as 3.732 and Maxwellian 21568 1 25 spectrum temperature 1.43 MeV. 21568 1 26 En,MeV Efficiency smoothed,% Efficiency ,% 21568 1 27 0.25 80.00 79.90 21568 1 28 0.50 79.80 77.90 21568 1 29 0.75 79.60 79.20 21568 1 30 1.00 79.30 80.70 21568 1 31 1.25 78.90 79.30 21568 1 32 1.50 78.40 79.30 21568 1 33 1.75 77.70 77.10 21568 1 34 2.00 76.90 77.20 21568 1 35 2.25 75.90 73.10 21568 1 36 2.50 74.90 71.90 21568 1 37 2.75 73.80 75.70 21568 1 38 3.00 72.70 74.30 21568 1 39 3.25 71.40 71.80 21568 1 40 3.50 70.30 70.10 21568 1 41 3.75 69.30 70.40 21568 1 42 4.00 68.40 68.50 21568 1 43 4.25 67.40 70.20 21568 1 44 4.50 66.40 66.60 21568 1 45 4.75 65.40 63.20 21568 1 46 5.00 64.60 64.60 21568 1 47 5.25 63.70 64.80 21568 1 48 5.50 62.90 61.70 21568 1 49 5.75 62.10 63.20 21568 1 50 6.00 61.30 60.60 21568 1 51 6.25 60.60 61.40 21568 1 52 6.50 59.90 59.20 21568 1 53 6.75 59.30 56.00 21568 1 54 7.00 58.80 56.40 21568 1 55 7.25 58.20 57.70 21568 1 56 7.50 57.50 59.20 21568 1 57 7.75 56.80 58.20 21568 1 58 8.00 56.00 56.90 21568 1 59 8.25 55.20 56.50 21568 1 60 8.50 54.20 51.00 21568 1 61 8.75 53.30 51.00 21568 1 62 9.00 52.30 53.90 21568 1 63 9.25 51.30 51.00 21568 1 64 9.50 50.20 49.80 21568 1 65 9.75 49.90 50.30 21568 1 66 10.00 49.50 49.90 21568 1 67 ASSUMED (ASSUM,98-CF-252(N,F),,NU) 21568 1 68 ANALYSIS Determination of the neutron multiplicity 21568 1 69 distribution for the detected events. 21568 1 70 CORRECTION Background, dead time, efficiency, multiple events, 21568 1 71 fission events with a multiplicity of 2 neutrons. 21568 1 72 COMMENT 1985-06-18 -Letter of J.Frehaut containing U-238 21568 1 73 data from NSE,74,29,1980 but corrected for the change 21568 1 74 in detection efficiency resulting from the difference 21568 1 75 between the energy spectra of (n,2n) and fission 21568 1 76 neutrons. 21568 1 77 HISTORY (19800609C) G.C. 21568 1 78 (19850618C) CN. 21568 1 79 (20170125A) M.M. Upper -> lower case correction. Dates 21568 1 80 were corrected for 4-digits year. REL-REFs were added. 21568 1 81 New ref. R,CEA-R-6447 was added. Subent 004 was added. 21568 1 82 EN-RSL->EN-RSL-HW. Ref. W,FREHAUT,19850618 was deleted.21568 1 83 (20230212A) SD: Correction in Subents 005, 006. 21568 1 84 ENDBIB 82 0 21568 1 85 COMMON 1 3 21568 1 86 ASSUM 21568 1 87 PRT/FIS 21568 1 88 3.732 21568 1 89 ENDCOMMON 3 0 21568 1 90 ENDSUBENT 89 0 21568 199999 SUBENT 21568002 20170125 225921568 2 1 BIB 8 13 21568 2 2 REACTION (92-U-235(N,2N)92-U-234,,SIG) 21568 2 3 INC-SOURCE (P-T) Proton-tritium reaction on gaseous target. 21568 2 4 SAMPLE .Metallic enriched sample. Disk of 25 mm diam., 21568 2 5 about 15 gram. 21568 2 6 MONITOR ((MONIT)92-U-235(N,F),,SIG) Taken from ENDF/B-5. 21568 2 7 MONIT-REF (,,3,ENDF/B-V,,1978) 21568 2 8 ERR-ANALYS (ERR-S) Statistical error only. No contribution for the21568 2 9 reference monitor reaction. 21568 2 10 STATUS (TABLE) Table 1, NSE,74,29,1980 21568 2 11 (SPSDD,21568004) Superseded by revised data 21568 2 12 HISTORY (19800609C) G.C. 21568 2 13 (19800612E) 21568 2 14 (20170225A) M.M. DATA-ERR -> ERR-S 21568 2 15 ENDBIB 13 0 21568 2 16 NOCOMMON 0 0 21568 2 17 DATA 5 16 21568 2 18 EN EN-RSL-HW MONIT DATA ERR-S 21568 2 19 MEV MEV B B B 21568 2 20 5.7300E+00 9.0000E-02 1.0600E+00 4.0000E-03 2.4000E-02 21568 2 21 5.9800E+00 9.0000E-02 1.1120E+00 1.2800E-01 2.3000E-02 21568 2 22 6.4900E+00 8.5000E-02 1.3640E+00 2.7300E-01 3.0000E-02 21568 2 23 7.0100E+00 8.0000E-02 1.5530E+00 3.5500E-01 3.2000E-02 21568 2 24 7.5200E+00 7.5000E-02 1.7200E+00 4.6300E-01 3.4000E-02 21568 2 25 8.0300E+00 7.5000E-02 1.7820E+00 4.8200E-01 3.8000E-02 21568 2 26 8.5400E+00 7.0000E-02 1.7820E+00 6.1400E-01 5.2000E-02 21568 2 27 9.0400E+00 6.5000E-02 1.7700E+00 6.4200E-01 4.3000E-02 21568 2 28 9.5500E+00 6.5000E-02 1.7600E+00 7.3400E-01 4.8000E-02 21568 2 29 1.0060E+01 6.0000E-02 1.7480E+00 7.7200E-01 5.5000E-02 21568 2 30 1.0560E+01 6.0000E-02 1.7370E+00 7.7500E-01 5.5000E-02 21568 2 31 1.1070E+01 5.5000E-02 1.7320E+00 8.5700E-01 6.6000E-02 21568 2 32 1.1570E+01 5.5000E-02 1.7340E+00 8.7000E-01 7.1000E-02 21568 2 33 1.2080E+01 5.5000E-02 1.7510E+00 8.5700E-01 8.5000E-02 21568 2 34 1.2580E+01 5.0000E-02 1.8400E+00 8.6300E-01 1.0900E-01 21568 2 35 1.3090E+01 5.0000E-02 1.9300E+00 7.1700E-01 1.1000E-01 21568 2 36 ENDDATA 18 0 21568 2 37 ENDSUBENT 36 0 21568 299999 SUBENT 21568003 20170125 225921568 3 1 BIB 8 17 21568 3 2 REACTION (92-U-238(N,2N)92-U-237,,SIG) 21568 3 3 INC-SOURCE (P-T) Proton-tritium reaction on gaseous target. 21568 3 4 SAMPLE .Metallic enriched sample. Disk of 25 mm diam., 21568 3 5 about 15 gram. 21568 3 6 MONITOR ((MONIT)92-U-238(N,F),,SIG) Taken from evaluation of 21568 3 7 Sowerby et al.,AERE-R-72/73 (1973). 21568 3 8 MONIT-REF (,M.G.Sowerby+,R,AERE-R-72/73,1973) 21568 3 9 ERR-ANALYS (ERR-S) Statistical error only. No contribution for the21568 3 10 reference monitor reaction. 21568 3 11 STATUS (TABLE) Data from Frehaut's letter of 18th June 1985. 21568 3 12 Prelim. data in Table 1 of NSE,74,29,1980 21568 3 13 (SPSDD,21568005) Superseded by revised data 21568 3 14 HISTORY (19800609C) G.C. 21568 3 15 (19800612E) 21568 3 16 (19850618C) CN. 21568 3 17 (19850723E) 21568 3 18 (20170225A) M.M. DATA-ERR -> ERR-S 21568 3 19 ENDBIB 17 0 21568 3 20 NOCOMMON 0 0 21568 3 21 DATA 5 14 21568 3 22 EN EN-RSL-HW MONIT DATA ERR-S 21568 3 23 MEV MEV B B B 21568 3 24 6.4900E+00 8.5000E-02 5.0000E-03 5.0000E-02 21568 3 25 7.0100E+00 8.0000E-02 8.7300E-01 3.0300E-01 4.4000E-02 21568 3 26 7.5200E+00 7.5000E-02 9.3100E-01 5.8400E-01 5.3000E-02 21568 3 27 8.0300E+00 7.5000E-02 9.5500E-01 8.3100E-01 7.0000E-02 21568 3 28 8.5400E+00 7.0000E-02 9.6300E-01 1.0790E+00 8.3000E-02 21568 3 29 9.0400E+00 6.5000E-02 9.6300E-01 1.1010E+00 8.3000E-02 21568 3 30 9.5500E+00 6.5000E-02 9.5800E-01 1.2150E+00 8.2000E-02 21568 3 31 1.0060E+01 6.0000E-02 9.5000E-01 1.2310E+00 9.3000E-02 21568 3 32 1.0560E+01 6.0000E-02 9.4800E-01 1.2580E+00 8.0000E-02 21568 3 33 1.1070E+01 5.5000E-02 9.5300E-01 1.3390E+00 9.7000E-02 21568 3 34 1.1570E+01 5.5000E-02 9.6000E-01 1.3470E+00 1.1500E-01 21568 3 35 1.2080E+01 5.5000E-02 9.7100E-01 1.3170E+00 9.8000E-02 21568 3 36 1.2580E+01 5.8000E-02 9.8800E-01 1.3030E+00 1.2500E-01 21568 3 37 1.3090E+01 5.0000E-02 1.0160E+00 1.2100E+00 1.0500E-01 21568 3 38 ENDDATA 16 0 21568 3 39 ENDSUBENT 38 0 21568 399999 SUBENT 21568004 20170125 225921568 4 1 BIB 8 37 21568 4 2 REACTION (92-U-235(N,2N)92-U-234,,SIG) 21568 4 3 INC-SOURCE (P-T) 21568 4 4 MONITOR (92-U-235(N,F),,SIG) 21568 4 5 En,MeV Standard2007 cross-section,barn 21568 4 6 5. 0.5467 21568 4 7 5.5 0.5463 21568 4 8 6. 0.6108 21568 4 9 6.5 0.8158 21568 4 10 7. 0.9387 21568 4 11 8. 1.0111 21568 4 12 9. 1.0094 21568 4 13 10. 1.0013 21568 4 14 11. 1.0019 21568 4 15 12. 0.9850 21568 4 16 13. 1.0151 21568 4 17 14. 1.1434 21568 4 18 15. 1.2346 21568 4 19 MONIT-REF (,,R,STI/PUB-1291,2007) 21568 4 20 International Evaluation of neutron cross-section 21568 4 21 Standards. IAEA,Vienna, 2007. 21568 4 22 CORRECTION Background correction. 21568 4 23 For dead time losses. 21568 4 24 Efficiency correction. 21568 4 25 Multiple event correction. 21568 4 26 For events not induced in sample. 21568 4 27 For (n,2n) reactions induced by non-monoenergetic 21568 4 28 neutrons. 21568 4 29 Correction in the flux measurement. 21568 4 30 For the effect of (n,2n) reaction in the axial tube 21568 4 31 of scintillator tank - estimated to be negligible. 21568 4 32 For reactions induced by degradated neutrons ( -3%) 21568 4 33 and loss of secondary neutrons in sample ( +0.5%) . 21568 4 34 ERR-ANALYS (DATA-ERR) Type of error is not explained. 21568 4 35 reference monitor reaction. 21568 4 36 STATUS (TABLE) Table 20 of R,CEA-R-6447,201611 21568 4 37 This Subent supersedes Subent 002. 21568 4 38 HISTORY (20170225C) M.M. Subent was added. 21568 4 39 ENDBIB 37 0 21568 4 40 NOCOMMON 0 0 21568 4 41 DATA 4 16 21568 4 42 EN EN-RSL-HW DATA DATA-ERR 21568 4 43 MEV MEV MB MB 21568 4 44 5.73 0.090 4. 24. 21568 4 45 5.98 0.090 126. 23. 21568 4 46 6.49 0.085 267. 30. 21568 4 47 7.01 0.080 352. 32. 21568 4 48 7.52 0.075 458. 34. 21568 4 49 8.03 0.115 483. 38. 21568 4 50 8.54 0.070 618. 52. 21568 4 51 9.04 0.065 645. 43. 21568 4 52 9.55 0.065 738. 48. 21568 4 53 10.06 0.060 776. 48. 21568 4 54 10.56 0.060 779. 55. 21568 4 55 11.07 0.055 857. 66. 21568 4 56 11.57 0.055 856. 71. 21568 4 57 12.08 0.055 849. 85. 21568 4 58 12.58 0.050 852. 109. 21568 4 59 13.09 0.050 707. 110. 21568 4 60 ENDDATA 18 0 21568 4 61 ENDSUBENT 60 0 21568 499999 SUBENT 21568005 20230212 231421568 5 1 BIB 8 36 21568 5 2 REACTION (92-U-238(N,2N)92-U-237,,SIG) 21568 5 3 INC-SOURCE (P-T,D-D) 21568 5 4 MONITOR (92-U-238(N,F),,SIG) 21568 5 5 Sowerby Standard2007 Ratio 21568 5 6 En,MeV Cross-section,barn No-dim.21568 5 7 6. 0.613 0.6108 0.9964 21568 5 8 6.5 0.753 0.8158 1.0834 21568 5 9 7. 0.874 0.9387 1.0740 21568 5 10 8. 0.956 1.0111 1.0576 21568 5 11 9. 0.963 1.0094 1.0482 21568 5 12 10. 0.952 1.0013 1.0518 21568 5 13 11. 0.954 1.0019 1.0502 21568 5 14 12. 0.966 0.9850 1.0197 21568 5 15 13. 1.008 1.0151 1.0070 21568 5 16 14. 1.126 1.1434 1.0155 21568 5 17 15. 1.238 1.2346 0.9973 21568 5 18 MONIT-REF (,,R,STI/PUB-1291,2007) 21568 5 19 International Evaluation of neutron cross-section 21568 5 20 Standards. IAEA,Vienna, 2007. 21568 5 21 CORRECTION Background correction. 21568 5 22 For dead time losses. 21568 5 23 Efficiency correction. 21568 5 24 Multiple event correction. 21568 5 25 For events not induced in sample. 21568 5 26 For (n,2n) reactions induced by non-monoenergetic 21568 5 27 neutrons. 21568 5 28 Correction in the flux measurement. 21568 5 29 For the effect of (n,2n) reaction in the axial tube 21568 5 30 of scintillator tank - estimated to be negligible. 21568 5 31 For reactions induced by degraded neutrons ( -3%) 21568 5 32 and loss of secondary neutrons in sample ( +0.5%) . 21568 5 33 ERR-ANALYS (DATA-ERR) Type of error is not explained. 21568 5 34 STATUS (TABLE) Table 19 of R,CEA-R-6447,201611 21568 5 35 This Subent supersedes Subents 21568.003 and 20416.02121568 5 36 HISTORY (20170225C) M.M. Subent was added. 21568 5 37 (20230212A) SD: SF1=U-235 -> U-238 in MONITOR. 21568 5 38 ENDBIB 36 0 21568 5 39 NOCOMMON 0 0 21568 5 40 DATA 4 36 21568 5 41 EN EN-RSL-HW DATA DATA-ERR 21568 5 42 MEV MEV MB MB 21568 5 43 6.49 0.085 27. 33. 21568 5 44 6.89 0.185 251. 39. 21568 5 45 7.01 0.080 315. 39. 21568 5 46 7.41 0.165 630. 27. 21568 5 47 7.52 0.075 697. 37. 21568 5 48 7.67 0.160 857. 62. 21568 5 49 7.93 0.150 916. 25. 21568 5 50 8.03 0.115 969. 39. 21568 5 51 8.18 0.145 1054. 41. 21568 5 52 8.44 0.135 1122. 26. 21568 5 53 8.54 0.070 1167. 40. 21568 5 54 8.69 0.130 1078. 60. 21568 5 55 8.94 0.125 1209. 20. 21568 5 56 9.04 0.065 1153. 61. 21568 5 57 9.44 0.115 1228. 23. 21568 5 58 9.55 0.065 1215. 56. 21568 5 59 9.93 0.110 1299. 22. 21568 5 60 10.06 0.06 1299. 55. 21568 5 61 10.19 0.105 1302. 65. 21568 5 62 10.42 0.100 1332. 24. 21568 5 63 10.56 0.060 1295. 54. 21568 5 64 10.74 0.095 1348. 71. 21568 5 65 10.91 0.095 1329. 22. 21568 5 66 11.07 0.055 1358. 59. 21568 5 67 11.40 0.090 1350. 26. 21568 5 68 11.57 0.055 1381. 84. 21568 5 69 11.88 0.085 1368. 23. 21568 5 70 12.08 0.055 1355. 47. 21568 5 71 12.36 0.085 1360. 31. 21568 5 72 12.58 0.050 1380. 64. 21568 5 73 12.85 0.080 1330. 23. 21568 5 74 13.09 0.050 1322. 72. 21568 5 75 13.33 0.075 1227. 29. 21568 5 76 13.80 0.075 1020. 27. 21568 5 77 14.28 0.070 904. 31. 21568 5 78 14.76 0.065 757. 32. 21568 5 79 ENDDATA 38 0 21568 5 80 ENDSUBENT 79 0 21568 599999 SUBENT 21568006 20230212 231421568 6 1 BIB 8 31 21568 6 2 REACTION (92-U-238(N,3N)92-U-236,,SIG) 21568 6 3 INC-SOURCE (D-D) 21568 6 4 MONITOR (92-U-238(N,F),,SIG) 21568 6 5 Sowerby Standard2007 Ratio 21568 6 6 En,MeV Cross-section,barn No-dim.21568 6 7 10. 0.952 1.0013 1.0518 21568 6 8 11. 0.954 1.0019 1.0502 21568 6 9 12. 0.966 0.9850 1.0197 21568 6 10 13. 1.008 1.0151 1.0070 21568 6 11 14. 1.126 1.1434 1.0155 21568 6 12 15. 1.238 1.2346 0.9973 21568 6 13 MONIT-REF (,,R,STI/PUB-1291,2007) 21568 6 14 International Evaluation of neutron cross-section 21568 6 15 Standards. IAEA,Vienna, 2007. 21568 6 16 CORRECTION Background correction. 21568 6 17 For dead time losses. 21568 6 18 Efficiency correction. 21568 6 19 Multiple event correction. 21568 6 20 For events not induced in sample. 21568 6 21 For (n,2n) reactions induced by non-monoenergetic 21568 6 22 neutrons. 21568 6 23 Correction in the flux measurement. 21568 6 24 For the effect of (n,2n) reaction in the axial tube 21568 6 25 of scintillator tank - estimated to be negligible. 21568 6 26 For reactions induced by degraded neutrons ( -3%) 21568 6 27 and loss of secondary neutrons in sample ( +0.5%) 21568 6 28 ERR-ANALYS (DATA-ERR) Type of error is not explained. 21568 6 29 STATUS (TABLE) Table 19 of R,CEA-R-6447,201611 21568 6 30 This Subent supersedes Subent 20416.022 21568 6 31 HISTORY (20170225C) M.M. Subent was added. 21568 6 32 (20230212A) SD: SF1=U-235 -> U-238 in MONITOR. 21568 6 33 ENDBIB 31 0 21568 6 34 NOCOMMON 0 0 21568 6 35 DATA 4 10 21568 6 36 EN EN-RSL-HW DATA DATA-ERR 21568 6 37 MEV MEV MB MB 21568 6 38 11.88 0.085 35. 11. 21568 6 39 12.08 0.055 42. 25. 21568 6 40 12.36 0.085 66. 13. 21568 6 41 12.58 0.050 106. 23. 21568 6 42 12.85 0.080 173. 12. 21568 6 43 13.09 0.050 188. 31. 21568 6 44 13.33 0.075 309. 16. 21568 6 45 13.80 0.075 407. 18. 21568 6 46 14.28 0.070 515. 24. 21568 6 47 14.76 0.065 585. 24. 21568 6 48 ENDDATA 12 0 21568 6 49 ENDSUBENT 48 0 21568 699999 ENDENTRY 6 0 2156899999999