ENTRY 41694 20210319 41954169400000001 SUBENT 41694001 20210319 41954169400100001 BIB 10 61 4169400100002 AUTHOR (Yu.S.Zamyatnin,D.K.Ryazanov,B.G.Basova,A.D.Rabinovich,4169400100003 V.A.Korostylev) 4169400100004 TITLE Prompt neutrons from fission of heavy nuclei 4169400100005 REFERENCE (J,SNP,29,305,1979) Eng.trans.of J,YF,29,595,1979 4169400100006 (J,YF,29,595,1979) Figures only. 4169400100007 INSTITUTE (4RUSNIR) 4169400100008 REL-REF (I,,B.G.Basova+,J,PTE,,(4),46,1975) 4169400100009 Details of ionization chamber. 4169400100010 (N,,B.G.Basova+,P,NIIAR-127,1971) 4169400100011 Algorithm of determination of fragment mass, velocity, 4169400100012 combined kinetic energy. 4169400100013 (M,,B.G.Basova+,P,NIIAR-269,1976) 4169400100014 (M,,B.G.Basova+,P,NIIAR-262,1975) 4169400100015 D.K.Ryazanov+,P,NIIAR-P-21(287),1976 - 4169400100016 details of analysis. 4169400100017 (N,40479001,Yu.S.Zamyatnin+,J,SNP,27,31,1978) 4169400100018 Eng.trans.of J,YF,27,(1),60,1978. 4169400100019 In this experiment for Pu-239 and Cf-252 the number of4169400100020 events was more than 1.E+7, ionization chamber working4169400100021 gas Ar + 3.% of N2. 4169400100022 METHOD (COINC) Coincidence of neutrons and fission fragments 4169400100023 (TOF) For separation of neutrons from prompt gammas. 4169400100024 Flight path 40. cm. 4169400100025 Mass resolution - 4 a.m.u., 4169400100026 kinetic energy resolution - 2.5 MeV. 4169400100027 Collimating of FF by mechanical collimator ( two 4169400100028 diaphragms of aperture diameter 8 mm, located coaxially4169400100029 of sample at 5.6 mm distance). 4169400100030 Two (two-dimensional 64x64 channel) sets were obtained-4169400100031 fragment-fragment double coincidences Nf(El,Eh), 4169400100032 fragment-fragment-neutron triple coincidences Nn(El,Eh)4169400100033 Number of counts at detector location 4169400100034 0 deg 90 deg 4169400100035 Cf-252 spont.fiss. 4169400100036 Nf 7841976 11228084 4169400100037 Nn 283441 98238 4169400100038 Pu-239 therm.neutr.fis. 4169400100039 Nf 1253081 486334 4169400100040 Nn 28778 2484 4169400100041 DETECTOR (COIN,IOCH,SCIN) Double ionization chamber, filled with4169400100042 96% Ar + 4.% of N2 to measure FF kinetic energy. 4169400100043 Plastic scintillator of 175 mm diameter, 70 mm 4169400100044 thickness for neutron registration by TOF; located at 4169400100045 angles 0 and 90 degrees to the fragment emission 4169400100046 direction; covered with Pb of 10 mm thickness. 4169400100047 Neutron registration energy range is 0.4 - 10 MeV. 4169400100048 Time resolution 4 nsec. 4169400100049 CORRECTION For detectors angular resolution, dependence of 4169400100050 neutron detector efficiency from neutron energy, 4169400100051 dependence of neutron spectrum average energy from 4169400100052 fragment mass. 4169400100053 ERR-ANALYS (ERR-1) Error due to detectors angular resolution - 2% 4169400100054 (ERR-2,4.,12.) Detection efficiency 4169400100055 for Cf - 4% for 0deg, 5% for 90 deg, up to 8% for 4169400100056 Nn-evap for 90 deg calculated from the data measured 4169400100057 at 0 deg; 4169400100058 for Pu - up to ~ 12 %. 4169400100059 (DATA-ERR) Type of uncertainty is not explained in 4169400100060 article. 4169400100061 HISTORY (20200909C)M.M. 4169400100062 (20210319U) COREL was added in STATUS of Subent 002. 4169400100063 ENDBIB 61 0 4169400100064 COMMON 1 3 4169400100065 ERR-1 4169400100066 PER-CENT 4169400100067 2. 4169400100068 ENDCOMMON 3 0 4169400100069 ENDSUBENT 68 0 4169400199999 SUBENT 41694002 20210319 41954169400200001 BIB 5 15 4169400200002 REACTION (98-CF-252(0,F)MASS,PR/FRG,NU) 4169400200003 SAMPLE Cf-252 was deposited on Al(2)O(3) (60 mug/cm2) by 4169400200004 vacuum evaporation, covered with Au (30 mug/cm2). 4169400200005 Sample activity 500 fis./sec . 4169400200006 REL-REF (A,14065001,H.R.Bowman+,J,PR,129,2133,1963) 4169400200007 (A,14065001,H.R.Bowman+,J,PR,126,2120,1962) 4169400200008 (A,,J.Terrell,J,PR,113,527,1959) 4169400200009 (A,,J.Terrell,J,PR,127,880,1962) 4169400200010 (A,,J.S.Fraser+,J,ARN,16,430,1966) 4169400200011 ERR-ANALYS Quantization errors (1/2 pixel): 4169400200012 scale X - 0.083 a.m.u., scale Y - 0.0044 prt/fis. 4169400200013 STATUS (CURVE) Fig.1 of Sov.Nucl.Phys.,v.29,p.305,1979 4169400200014 (COREL,40420002) Measurement by different sample - 4169400200015 backing Al(2)O(3) (thickness 30 mug/cm**2) 4169400200016 covered by gold film (thickness 10 mug/cm**2) 4169400200017 ENDBIB 15 0 4169400200018 COMMON 2 3 4169400200019 MASS-ERR-D ERR-DIG 4169400200020 NO-DIM PRT/FIS 4169400200021 0.069 0.0038 4169400200022 ENDCOMMON 3 0 4169400200023 DATA 3 60 4169400200024 MASS DATA DATA-ERR 4169400200025 NO-DIM PRT/FIS PRT/FIS 4169400200026 80.230 0.6030 0.1406 4169400200027 81.217 0.8053 0.1230 4169400200028 82.880 0.8583 0.1230 4169400200029 84.206 0.9727 0.1318 4169400200030 85.698 1.1136 0.0791 4169400200031 87.030 1.1226 0.0967 4169400200032 88.861 1.1668 0.1142 4169400200033 90.194 1.1671 0.1054 4169400200034 91.688 1.2640 0.0703 4169400200035 93.355 1.2643 0.0615 4169400200036 94.688 1.2733 0.0527 4169400200037 96.184 1.3263 0.0527 4169400200038 97.851 1.3266 0.0615 4169400200039 99.350 1.3356 0.0439 4169400200040 100.680 1.3886 0.0440 4169400200041 102.180 1.4240 0.0439 4169400200042 103.840 1.4770 0.0527 4169400200043 105.330 1.6442 0.0352 4169400200044 106.650 1.8465 0.0439 4169400200045 108.310 2.0313 0.0528 4169400200046 109.800 2.1897 0.0352 4169400200047 111.290 2.3306 0.0528 4169400200048 112.950 2.4363 0.0527 4169400200049 114.430 2.6474 0.0439 4169400200050 115.760 2.7443 0.0615 4169400200051 117.420 2.9467 0.0527 4169400200052 118.740 3.0436 0.0703 4169400200053 120.220 3.3514 0.0791 4169400200054 121.540 3.6152 0.1142 4169400200055 123.040 3.7033 0.1055 4169400200056 124.880 3.5982 0.1318 4169400200057 126.150 1.9465 0.1318 4169400200058 127.660 1.6393 0.0967 4169400200059 129.030 1.1563 0.0703 4169400200060 130.380 0.8226 0.0527 4169400200061 131.880 0.8404 0.0527 4169400200062 133.380 0.8758 0.0528 4169400200063 136.190 1.1839 0.0439 4169400200064 137.690 1.2808 0.0439 4169400200065 139.510 1.3865 0.0527 4169400200066 140.840 1.4395 0.0615 4169400200067 142.510 1.4925 0.0527 4169400200068 143.840 1.5367 0.0527 4169400200069 145.490 1.6951 0.0527 4169400200070 146.990 1.8008 0.0615 4169400200071 148.480 1.9856 0.0615 4169400200072 149.970 2.1352 0.0527 4169400200073 151.460 2.2848 0.0703 4169400200074 152.940 2.4960 0.0967 4169400200075 154.600 2.6983 0.0879 4169400200076 155.920 2.8567 0.1143 4169400200077 157.750 3.0064 0.1054 4169400200078 159.080 2.9627 0.1318 4169400200079 160.580 3.0069 0.1669 4169400200080 162.070 3.1829 0.2109 4169400200081 163.700 3.7280 0.1933 4169400200082 165.210 3.5173 0.3075 4169400200083 166.720 3.3770 0.4393 4169400200084 168.360 3.8430 0.6151 4169400200085 170.030 3.7203 0.9577 4169400200086 ENDDATA 62 0 4169400200087 ENDSUBENT 86 0 4169400299999 SUBENT 41694003 20200909 41894169400300001 BIB 6 10 4169400300002 REACTION (94-PU-239(N,F)MASS,PR/FRG,NU,,SPA) 4169400300003 INC-SPECT Thermal neutrons . 4169400300004 SAMPLE Pu-239 was deposited electrically on a Au-covered 4169400300005 organic film 4169400300006 REL-REF (A,,B.G.Basova+,C,75KIEV,5,160,1975) 4169400300007 (A,,H.Nifenecker+,C,73ROCH,2,117,1973) 4169400300008 paper SM-174/207 4169400300009 ERR-ANALYS Quantization errors (1/2 pixel): 4169400300010 scale X - 0.077 a.m.u., scale Y - 0.0032 prt/fis. 4169400300011 STATUS (CURVE) Fig.2 of Sov.Nucl.Phys.,v.29,p.305,1979 4169400300012 ENDBIB 10 0 4169400300013 COMMON 3 3 4169400300014 EN-DUMMY MASS-ERR-D ERR-DIG 4169400300015 EV NO-DIM PRT/FIS 4169400300016 2.53E-02 0.055 0.0032 4169400300017 ENDCOMMON 3 0 4169400300018 DATA 3 62 4169400300019 MASS DATA DATA-ERR 4169400300020 NO-DIM PRT/FIS PRT/FIS 4169400300021 73.794 0.5604 0.3373 4169400300022 75.342 0.7003 0.2737 4169400300023 76.891 0.9357 0.2037 4169400300024 77.968 0.7257 0.1273 4169400300025 79.665 0.6492 0.0955 4169400300026 81.063 1.0119 0.1273 4169400300027 82.759 0.8909 0.1018 4169400300028 84.151 1.0118 0.0636 4169400300029 85.695 0.9799 0.0573 4169400300030 87.242 1.0880 0.0636 4169400300031 88.635 1.2089 0.0700 4169400300032 90.179 1.2025 0.0509 4169400300033 91.881 1.3361 0.0446 4169400300034 93.115 1.2978 0.0382 4169400300035 94.661 1.3678 0.0382 4169400300036 96.362 1.4441 0.0382 4169400300037 97.906 1.4567 0.0446 4169400300038 99.142 1.4631 0.0446 4169400300039 100.840 1.4566 4169400300040 102.230 1.5457 4169400300041 103.780 1.5138 0.0318 4169400300042 105.320 1.6156 0.0318 4169400300043 106.560 1.8128 0.0255 4169400300044 107.960 1.9591 0.0318 4169400300045 109.360 2.3664 0.0509 4169400300046 110.750 2.6145 0.0636 4169400300047 112.300 2.8245 0.1273 4169400300048 113.700 3.2190 0.2100 4169400300049 115.390 2.8116 0.3055 4169400300050 116.620 2.4488 0.2991 4169400300051 118.460 2.2578 0.2800 4169400300052 119.710 2.4933 0.4137 4169400300053 121.240 1.8950 0.3373 4169400300054 122.930 1.8949 0.3309 4169400300055 124.320 1.6976 0.2991 4169400300056 126.000 0.7047 0.1209 4169400300057 127.540 0.5774 0.0955 4169400300058 129.230 0.3736 0.0636 4169400300059 130.310 0.4245 0.0509 4169400300060 132.010 0.3799 0.0446 4169400300061 133.410 0.5389 0.0446 4169400300062 134.950 0.7489 0.0573 4169400300063 136.350 1.0607 0.0255 4169400300064 137.900 1.2197 0.0382 4169400300065 139.450 1.3469 0.0318 4169400300066 141.150 1.3787 0.0318 4169400300067 142.540 1.4996 0.0318 4169400300068 144.240 1.5695 0.0318 4169400300069 145.480 1.6967 0.0382 4169400300070 147.180 1.8940 0.0318 4169400300071 148.570 1.9321 0.0573 4169400300072 150.120 1.9766 0.0827 4169400300073 151.810 1.9001 0.0827 4169400300074 153.060 2.2947 0.1464 4169400300075 154.610 2.5555 0.1527 4169400300076 156.150 2.5809 0.1655 4169400300077 157.710 2.8673 0.2673 4169400300078 159.090 2.7845 0.3437 4169400300079 160.940 2.4726 0.3437 4169400300080 162.030 2.7844 0.4773 4169400300081 163.880 2.8925 0.5473 4169400300082 165.430 3.2043 0.5919 4169400300083 ENDDATA 64 0 4169400300084 ENDSUBENT 83 0 4169400399999 SUBENT 41694004 20200909 41894169400400001 BIB 6 9 4169400400002 REACTION (94-PU-239(N,F)MASS,PR,NU,,SPA) 4169400400003 INC-SPECT Thermal neutrons . 4169400400004 SAMPLE Pu-239 was deposited electrically on a Au-covered 4169400400005 organic film 4169400400006 REL-REF (A,,H.Nifenecker+,C,73ROCH,2,117,1973) 4169400400007 paper SM-174/207 4169400400008 ERR-ANALYS Quantization errors (1/2 pixel): 4169400400009 scale X - 0.077 a.m.u., scale Y - 0.021 prt/fis. 4169400400010 STATUS (CURVE) Fig.2 of Sov.Nucl.Phys.,v.29,p.305,1979 4169400400011 ENDBIB 9 0 4169400400012 COMMON 3 3 4169400400013 EN-DUMMY MASS-ERR-D ERR-DIG 4169400400014 EV NO-DIM PRT/FIS 4169400400015 2.53E-02 0.063 0.017 4169400400016 ENDCOMMON 3 0 4169400400017 DATA 3 30 4169400400018 MASS DATA DATA-ERR 4169400400019 NO-DIM PRT/FIS PRT/FIS 4169400400020 118.86 4.585 0.497 4169400400021 120.56 4.295 0.539 4169400400022 122.26 4.751 0.331 4169400400023 123.49 5.538 0.290 4169400400024 125.50 4.709 0.290 4169400400025 126.74 4.295 4169400400026 128.13 3.715 4169400400027 129.36 2.970 4169400400028 130.91 2.514 4169400400029 132.30 2.224 4169400400030 135.54 2.390 4169400400031 137.08 2.639 4169400400032 138.63 2.763 4169400400033 140.33 2.846 4169400400034 141.72 3.012 4169400400035 143.42 3.012 4169400400036 144.96 3.053 4169400400037 146.19 3.302 4169400400038 147.58 3.302 4169400400039 149.44 3.178 4169400400040 151.14 3.054 4169400400041 152.53 3.592 4169400400042 153.92 3.758 4169400400043 155.46 3.841 4169400400044 156.85 4.090 0.456 4169400400045 158.55 3.344 4169400400046 160.40 3.303 0.539 4169400400047 161.64 4.090 4169400400048 163.18 4.421 4169400400049 164.73 4.256 0.994 4169400400050 ENDDATA 32 0 4169400400051 ENDSUBENT 50 0 4169400499999 SUBENT 41694005 20200909 41894169400500001 BIB 6 27 4169400500002 REACTION 1(98-CF-252(0,F),PR,NU/TKE,,MSC,DERIV) 4169400500003 Fig.5b - NUevap - neutrons from completely accelerated 4169400500004 fragments ( part of total prompt neutrons) 4169400500005 2(98-CF-252(0,F),PR,NU/TKE,,MSC,DERIV) 4169400500006 Fig.5c - scission neutrons. 4169400500007 . Dependence from kinetic energy of fission fragments. 4169400500008 SAMPLE Cf-252 was deposited on Al(2)O(3) (60 mug/cm2) by 4169400500009 vacuum evaporation, covered with Au (30 mug/cm2). 4169400500010 Sample activity 500 fis./sec . 4169400500011 ANALYSIS It was assumed : 4169400500012 - at 0 deg - neutrons evaporated from fully accelerated4169400500013 fragments (evaporated neutrons), corresponding to 4169400500014 time > 5.E-21 sec; contribution of scission neutrons 4169400500015 is small. 4169400500016 - at 90 deg - there are evaporated neutrons and 4169400500017 neutrons emitted before complete acceleration of 4169400500018 fragments. 4169400500019 - spectrum of scission neutrons is Maxwellian with 4169400500020 average energy 2.5 MeV, angular distribution is 4169400500021 isotropic. 4169400500022 2 See formula (4) for derived yield of scission neutrons4169400500023 MISC-COL (MISC) Fig5a - ratio at 90 deg Nexperimental/Nevapor. 4169400500024 ERR-ANALYS Quantization errors (1/2 pixel): 4169400500025 Fig.1b: scale X - 0.083 MeV, scale Y - 0.017 prt/fis; 4169400500026 Fig.1c: scale X - 0.083 MeV, scale Y - 0.0034 prt/fis; 4169400500027 (ERR-S) Statistical error 4169400500028 STATUS (CURVE) Fig.5 of Sov.Nucl.Phys.,v.29,p.305,1979 4169400500029 ENDBIB 27 0 4169400500030 COMMON 3 3 4169400500031 E-ERR-DIG 1ERR-DIG 1ERR-DIG 2 4169400500032 MEV PRT/FIS PRT/FIS 4169400500033 0.068 0.0093 0.0026 4169400500034 ENDCOMMON 3 0 4169400500035 DATA 6 26 4169400500036 TKE DATA 1DATA-ERR 1DATA 2ERR-S MISC 4169400500037 MEV PRT/FIS PRT/FIS PRT/FIS PRT/FIS NO-DIM 4169400500038 155.01 5.7131 0.2985 0.3228 0.2115 4169400500039 157.40 5.7076 0.2671 0.2113 1.0796 4169400500040 159.95 5.5693 0.0544 0.1229 1.0153 4169400500041 162.41 5.5306 -0.0899 0.0955 0.9677 4169400500042 165.16 5.4248 -0.0708 0.0682 0.9671 4169400500043 167.65 5.3529 0.0372 0.0613 1.0069 4169400500044 170.06 5.1482 0.0155 0.0682 0.9997 4169400500045 172.50 4.9767 0.1712 0.0477 1.0429 4169400500046 175.09 4.7716 0.2313 0.0409 1.0491 4169400500047 177.51 4.5004 0.2574 0.0409 1.0721 4169400500048 180.21 4.1621 0.3175 0.0409 1.1287 4169400500049 182.42 3.9585 0.3435 0.0477 1.1551 4169400500050 185.01 3.6534 0.3833 0.0477 1.1949 4169400500051 187.44 3.5819 0.4639 0.0477 1.2179 4169400500052 189.97 3.4104 0.4558 0.0546 1.2409 4169400500053 192.45 3.2056 0.4955 0.0409 1.2505 4169400500054 194.87 3.0016 0.4943 0.0545 1.2768 4169400500055 197.45 2.7958 0.5340 0.0818 1.2931 4169400500056 199.76 2.6582 0.5397 0.0886 1.2893 4169400500057 202.46 2.4860 0.5930 0.0954 1.3324 4169400500058 204.84 2.2820 0.6735 0.1569 1.3655 4169400500059 207.20 2.1101 0.6383 0.2113 1.3819 4169400500060 209.82 2.0050 0.3650 0.5757 0.2454 1.2738 4169400500061 212.41 1.9656 0.5314 0.4858 0.2659 1.3943 4169400500062 214.81 0.6687 0.2455 1.3467 4169400500063 217.28 0.5585 0.2726 1.4167 4169400500064 ENDDATA 28 0 4169400500065 ENDSUBENT 64 0 4169400599999 SUBENT 41694006 20200909 41894169400600001 BIB 7 27 4169400600002 REACTION 1(94-PU-239(N,F),PR,NU/TKE,,SPA/MSC,DERIV) 4169400600003 Fig.7b - NUevap - neutrons from completely accelerated 4169400600004 fragments ( part of total prompt neutrons) 4169400600005 2(94-PU-239(N,F),PR,NU/TKE,,SPA/MSC,DERIV) 4169400600006 Fig.7c - scission neutrons. 4169400600007 . Dependence from kinetic energy of fission fragments. 4169400600008 INC-SPECT Thermal neutrons . 4169400600009 SAMPLE Pu-239 was deposited electrically on a Au-covered 4169400600010 organic film 4169400600011 ANALYSIS It was assumed : 4169400600012 - at 0 deg - neutrons evaporated from fully accelerated4169400600013 fragments (evaporated neutrons), corresponding to 4169400600014 time > 5.E-21 sec; contribution of scission neutrons 4169400600015 is small. 4169400600016 - at 90 deg - there are evaporated neutrons and 4169400600017 neutrons emitted before complete acceleration of 4169400600018 fragments. 4169400600019 - spectrum of scission neutrons is Maxwellian with 4169400600020 average energy 2.5 MeV, angular distribution is 4169400600021 isotropic. 4169400600022 2 See formula (4) for derived yield of scission neutrons4169400600023 MISC-COL (MISC) Fig.7a - ratio at 90 deg Nexperimental/Nevapor. 4169400600024 ERR-ANALYS Quantization errors (1/2 pixel): 4169400600025 Fig.1b: scale X - 0.069 MeV, scale Y - 0.014 prt/fis; 4169400600026 Fig.1c: scale X - 0.069 MeV, scale Y - 0.003 prt/fis; 4169400600027 (ERR-S) Statistical error 4169400600028 STATUS (CURVE) Fig.7 of Sov.Nucl.Phys.,v.29,p.305,1979 4169400600029 ENDBIB 27 0 4169400600030 COMMON 4 3 4169400600031 EN-DUMMY E-ERR-DIG 1ERR-DIG 1ERR-DIG 2 4169400600032 EV MEV PRT/FIS PRT/FIS 4169400600033 2.53E-02 0.056 0.011 0.023 4169400600034 ENDCOMMON 3 0 4169400600035 DATA 6 23 4169400600036 TKE DATA 1DATA-ERR 1DATA 2ERR-S MISC 4169400600037 MEV PRT/FIS PRT/FIS PRT/FIS PRT/FIS NO-DIM 4169400600038 147.84 5.457 0.369 4169400600039 150.45 5.231 0.255 4169400600040 152.93 4.834 4169400600041 155.40 4.863 4169400600042 158.01 4.580 4169400600043 160.48 4.297 4169400600044 162.96 4.071 4169400600045 165.33 3.760 0.192 0.102 1.0971 4169400600046 167.90 3.477 0.095 0.057 1.0517 4169400600047 170.24 3.251 0.152 0.057 1.0601 4169400600048 172.67 2.911 0.379 0.096 1.1366 4169400600049 175.23 2.855 0.487 0.102 1.1932 4169400600050 177.66 2.628 0.590 0.085 1.2527 4169400600051 180.14 2.431 0.397 0.085 1.1675 4169400600052 182.52 2.119 0.647 0.182 1.2837 4169400600053 185.09 1.865 0.647 0.193 1.2921 4169400600054 187.70 1.639 0.517 0.119 1.2608 4169400600055 190.45 1.497 4169400600056 192.92 1.328 4169400600057 195.39 0.960 4169400600058 198.00 1.046 4169400600059 200.34 0.677 0.255 4169400600060 202.95 0.366 0.312 4169400600061 ENDDATA 25 0 4169400600062 ENDSUBENT 61 0 4169400699999 ENDENTRY 6 0 4169499999999