ENTRY 21546 20230207 2154600000001 SUBENT 21546001 20230207 20231011 2154600100001 BIB 13 57 2154600100002 TITLE Measurement of the fission neutron energy spectra 2154600100003 for the fast neutron-induced fission of U-235 and 2154600100004 U-238 2154600100005 AUTHOR (A.Bertin,R.Bois,J.Frehaut) 2154600100006 REFERENCE ((R,INDC(FR)-27,1978)=(R,CEA-R-4913,1978)) in French 2154600100007 (J,ANS,32,732,1979) 2154600100008 (P,CEA-N-1875,71,1976) in French 2154600100009 (J,ANS,22,667,1975) 2154600100010 (C,75KIEV,5,349,1975) 2154600100011 INSTITUTE (2FR BRC) 2154600100012 FACILITY (VDG,2FR BRC) 4 MeV, 1 ns puls-width, 1 MHz repetition 2154600100013 rate, 3 to 4 uA average current. 2154600100014 INC-SOURCE (P-LI7) Solid target of 430 ug/cm2, proton 2154600100015 energy 2.35 MeV for production of 600 keV neutrons. 2154600100016 (D-D) Deuteron-deuterium reaction on gaseous 2154600100017 target, 1 cm long, at 2. atm. pressure, deuteron 2154600100018 energy 4 MeV, entrance window of Havar of 2 microns 2154600100019 thickness for the production of 7 MeV neutrons. The 2154600100020 energy loss in the target is 34 keV. 2154600100021 SAMPLE Massif U hollow cylinder, 2 cm outer diam, 1 cm inner 2154600100022 diam, 3 cm high, 93.5% enriched in U-235 for the 2154600100023 sample method. 100 disks of stainless steel, 80 mm 2154600100024 diam, 0.2 mm thick at distances of 1 mm, with 1 mg/cm2 2154600100025 fissile material, in the fission chamber method. 2154600100026 METHOD (TOF) Time-of-flight to detect the fission neutron 2154600100027 energy. Two methods of measurement were used. The 2154600100028 sample method (2 m flight path, 600 keV neutrons) 2154600100029 uses a massif sample. The fission chamber method uses 2154600100030 thin deposits (1.4 m flight path, 600 keV and 2 m 2154600100031 flight path, 7 MeV). In this method the incoming 2154600100032 neutron energy is also measured by TOF. 2154600100033 DETECTOR (SCIN ) Liquid scintillator NE213, diam=10 cm, 2154600100034 thickness 5 cm, coupled to a fast photomultiplier (PM)2154600100035 XP1041 at an angle of 90 degr. With respect to the 2154600100036 neutron beam, at 2 m from the sample. Its efficiency 2154600100037 was determined in 3 ways. 2154600100038 (SCIN) For neutron flux measurements, liquid 2154600100039 scintillator, NE102, 1 in * 1 in, PM-tube 56AVP. 2154600100040 (FISCH) Fission chamber filled with 80% argon, 2154600100041 20% methane, under 4 kJ pressure. 2154600100042 COMMENT The fission neutron spectrum does not have a 2154600100043 Maxwellian shape, due to an excess in the low 2154600100044 energy part of the spectrum. The two methods of 2154600100045 measurement are compared in table 3 of the 2154600100046 publication. Also different energy intervals 2154600100047 are considered to determine the average neutron 2154600100048 energy. 2154600100049 CORRECTION Off time slow neutron-induced fission background 2154600100050 (by a delayed random coincidence method) and 2154600100051 secondary effects. 2154600100052 ERR-ANALYS (DATA-ERR) Statistical + systematic (efficiency) 2154600100053 errors. 2154600100054 HISTORY (19800514C) G.C. 2154600100055 (20201016A) SD:Updated to new date formats,lower case. 2154600100056 Corrections in all Subents. Page of ref.ANS,32, 2154600100057 corrected (p.733 ->732). 2154600100058 (20230207A) SD: Subents 003, 004 were added. 2154600100059 ENDBIB 57 0 2154600100060 NOCOMMON 0 0 2154600100061 ENDSUBENT 60 0 2154600199999 SUBENT 21546002 20201016 22942154600200001 BIB 4 5 2154600200002 REACTION (92-U-235(N,F)0-NN-1,PR,KE) 2154600200003 SAMPLE (92-U-235,ENR=0.935) 2154600200004 STATUS (TABLE) text on p.26 of CEA-R-4913. 2154600200005 HISTORY (20201016A) SD: SF4=NN-1 added; SF6=AKE -> KE; SF7=N 2154600200006 deleted from REACTION code. STATUS updated. 2154600200007 ENDBIB 5 0 2154600200008 COMMON 1 3 2154600200009 DATA-ERR 2154600200010 MEV 2154600200011 0.006 2154600200012 ENDCOMMON 3 0 2154600200013 DATA 3 2 2154600200014 EN EN-ERR DATA 2154600200015 MEV MEV MEV 2154600200016 0.600 0.05 2.04 2154600200017 7. 0.035 2.14 2154600200018 ENDDATA 4 0 2154600200019 ENDSUBENT 18 0 2154600299999 SUBENT 21546003 20201016 22942154600300001 BIB 3 4 2154600300002 REACTION (92-U-238(N,F)0-NN-1,PR,KE) 2154600300003 STATUS (TABLE) text on p.26 of CEA-R-4913. 2154600300004 HISTORY (20201016A) SD: SF4=NN-1 added; SF6=AKE -> KE; SF7=N 2154600300005 deleted from REACTION code. STATUS updated. 2154600300006 ENDBIB 4 0 2154600300007 NOCOMMON 0 0 2154600300008 DATA 4 1 2154600300009 EN EN-ERR DATA DATA-ERR 2154600300010 MEV MEV MEV MEV 2154600300011 7. 0.035 2.07 0.07 2154600300012 ENDDATA 3 0 2154600300013 ENDSUBENT 12 0 2154600399999 SUBENT 21546004 20230207 20231011 2154600400001 BIB 4 6 2154600400002 REACTION (92-U-235(N,F)0-NN-1,PR,NU/DE,,RRE/REL) 2154600400003 N(E)/sqrt(E) 2154600400004 SAMPLE (92-U-235,ENR=0.935) 2154600400005 STATUS (CURVE) Fig.14 of CEA-R-4913 (same on fig.1 of 2154600400006 Trans.Am.Nuc.Soc.,32,732,1979, only for E=7MeV). 2154600400007 HISTORY (20230207C) SD 2154600400008 ENDBIB 6 0 2154600400009 COMMON 2 3 2154600400010 E-ERR-DIG ERR-DIG 2154600400011 MEV PER-CENT 2154600400012 0.016 1.5 2154600400013 ENDCOMMON 3 0 2154600400014 DATA 4 53 2154600400015 EN E DATA DATA-ERR 2154600400016 MEV MEV ARB-UNITS ARB-UNITS 2154600400017 0.6 0.354 3.650E+04 4.747E+03 2154600400018 0.6 0.398 3.804E+04 3.240E+03 2154600400019 0.6 0.510 3.302E+04 2.804E+03 2154600400020 0.6 0.624 2.752E+04 1.735E+03 2154600400021 0.6 0.804 2.160E+04 1.361E+03 2154600400022 0.6 0.962 1.876E+04 2.012E+03 2154600400023 0.6 1.119 1.564E+04 1.328E+03 2154600400024 0.6 1.298 1.474E+04 1.252E+03 2154600400025 0.6 1.545 1.181E+04 1.003E+03 2154600400026 0.6 1.836 9.471E+03 8.042E+02 2154600400027 0.6 2.262 7.009E+03 4.418E+02 2154600400028 0.6 2.845 4.415E+03 2.771E+02 2154600400029 0.6 3.675 2.274E+03 1.427E+02 2154600400030 0.6 4.952 9.600E+02 8.177E+01 2154600400031 0.6 7.389 2.368E+02 2.539E+01 2154600400032 0.6 9.791 2.919E+01 7.334E+00 2154600400033 7.0 0.391 1.856E+05 3.424E+04 2154600400034 7.0 0.479 1.858E+05 1.882E+04 2154600400035 7.0 0.523 1.814E+05 1.843E+04 2154600400036 7.0 0.589 1.860E+05 1.890E+04 2154600400037 7.0 0.679 1.572E+05 1.183E+04 2154600400038 7.0 0.769 1.297E+05 1.317E+04 2154600400039 7.0 0.879 1.237E+05 9.311E+03 2154600400040 7.0 0.990 1.124E+05 1.142E+04 2154600400041 7.0 1.079 9.735E+04 1.249E+04 2154600400042 7.0 1.168 9.285E+04 1.194E+04 2154600400043 7.0 1.258 7.659E+04 7.781E+03 2154600400044 7.0 1.368 7.485E+04 5.634E+03 2154600400045 7.0 1.501 6.643E+04 6.749E+03 2154600400046 7.0 1.656 6.041E+04 6.120E+03 2154600400047 7.0 1.833 5.364E+04 5.434E+03 2154600400048 7.0 1.966 5.119E+04 6.596E+03 2154600400049 7.0 2.077 4.766E+04 6.128E+03 2154600400050 7.0 2.188 4.128E+04 5.295E+03 2154600400051 7.0 2.321 3.753E+04 4.825E+03 2154600400052 7.0 2.476 3.496E+04 3.542E+03 2154600400053 7.0 2.609 3.029E+04 3.077E+03 2154600400054 7.0 2.809 2.626E+04 3.368E+03 2154600400055 7.0 2.986 2.388E+04 3.064E+03 2154600400056 7.0 3.186 1.926E+04 2.476E+03 2154600400057 7.0 3.408 1.591E+04 2.480E+03 2154600400058 7.0 3.651 1.448E+04 2.266E+03 2154600400059 7.0 3.939 1.169E+04 1.826E+03 2154600400060 7.0 4.249 9.903E+03 1.550E+03 2154600400061 7.0 4.603 7.807E+03 1.220E+03 2154600400062 7.0 5.001 6.784E+03 1.060E+03 2154600400063 7.0 5.449 2.996E+03 9.133E+02 2154600400064 7.0 5.955 2.871E+03 6.983E+02 2154600400065 7.0 6.528 2.821E+03 6.871E+02 2154600400066 7.0 7.258 1.797E+03 5.478E+02 2154600400067 7.0 8.120 1.233E+03 2.994E+02 2154600400068 7.0 9.082 2.525E+02 3.083E+02 2154600400069 7.0 9.792 1.357E+02 1.964E+02 2154600400070 ENDDATA 55 0 2154600400071 ENDSUBENT 70 0 2154600499999 SUBENT 21546005 20230207 20231011 2154600500001 BIB 3 4 2154600500002 REACTION (92-U-238(N,F)0-NN-1,PR,NU/DE,,RRE/REL) 2154600500003 STATUS (CURVE) Fig.14 of CEA-R-4913 (same on fig.1 of 2154600500004 Trans.Am.Nuc.Soc.,32,732,1979). 2154600500005 HISTORY (20230207C) SD 2154600500006 ENDBIB 4 0 2154600500007 COMMON 3 3 2154600500008 E-ERR-DIG ERR-DIG EN 2154600500009 MEV PER-CENT MEV 2154600500010 0.016 1.5 7.0 2154600500011 ENDCOMMON 3 0 2154600500012 DATA 3 37 2154600500013 E DATA DATA-ERR 2154600500014 MEV ARB-UNITS ARB-UNITS 2154600500015 0.374 1.094E+04 1.476E+03 2154600500016 0.440 1.178E+04 1.832E+03 2154600500017 0.527 1.237E+04 1.591E+03 2154600500018 0.595 1.045E+04 1.065E+03 2154600500019 0.683 1.021E+04 1.038E+03 2154600500020 0.773 8.426E+03 8.560E+02 2154600500021 0.884 7.297E+03 5.512E+02 2154600500022 0.996 6.474E+03 8.323E+02 2154600500023 1.064 5.211E+03 8.140E+02 2154600500024 1.151 5.609E+03 8.778E+02 2154600500025 1.264 4.003E+03 5.147E+02 2154600500026 1.374 4.207E+03 5.409E+02 2154600500027 1.507 3.644E+03 4.685E+02 2154600500028 1.662 3.314E+03 3.367E+02 2154600500029 1.818 2.871E+03 3.700E+02 2154600500030 1.996 2.371E+03 3.048E+02 2154600500031 2.105 2.492E+03 3.204E+02 2154600500032 2.215 2.619E+03 3.359E+02 2154600500033 2.326 2.214E+03 3.458E+02 2154600500034 2.482 1.965E+03 3.626E+02 2154600500035 2.637 1.703E+03 2.659E+02 2154600500036 2.794 1.276E+03 2.354E+02 2154600500037 2.993 1.189E+03 1.858E+02 2154600500038 3.214 1.082E+03 1.688E+02 2154600500039 3.413 9.849E+02 1.817E+02 2154600500040 3.636 7.038E+02 1.503E+02 2154600500041 3.942 8.571E+02 1.339E+02 2154600500042 4.255 5.432E+02 1.002E+02 2154600500043 4.591 2.838E+02 7.757E+01 2154600500044 5.053 2.995E+02 8.196E+01 2154600500045 5.433 1.565E+02 5.790E+01 2154600500046 5.966 1.019E+02 4.812E+01 2154600500047 6.582 1.002E+02 5.096E+01 2154600500048 7.545 1.733E+01 2.940E+01 2154600500049 8.151 4.938E+01 2.510E+01 2154600500050 9.060 2.597E+01 1.320E+01 2154600500051 9.519 3.770E+00 9.820E+00 2154600500052 ENDDATA 39 0 2154600500053 ENDSUBENT 52 0 2154600599999 ENDENTRY 3 0 2154699999999