ENTRY 12396 20220210 14981239600000001 SUBENT 12396001 20220210 14981239600100001 BIB 12 58 1239600100002 TITLE Total neutron cross sections for 235U, normal uranium, 1239600100003 239Pu 1239600100004 AUTHOR (R.L.Henkel,L.Cranberg,R.B.Day,G.A.Jarvis,R.Nobles, 1239600100005 J.E.Perry) 1239600100006 REFERENCE (R,LA-1493,1952) 1239600100007 REL-REF (A,12370001,H.H.Barschall,R,LA-1060,1950) 1239600100008 INSTITUTE (1USALAS) 1239600100009 FACILITY (VDG,1USALAS) 1239600100010 INC-SOURCE (P-LI7,P-T,D-D) Monoenergetic neutrons were produced 1239600100011 from three sources for the present work. For the 1239600100012 neutron energy interval between 40 and 200 keV, the 1239600100013 Li(p,n)Be7 source was used with evaporated lithium 1239600100014 targets of about 10 keV stopping power. Between 160 1239600100015 and 350 keV, neutrons were produced by the T(p,n)He3 1239600100016 reaction with a tritium gas target having 30 to 10 1239600100017 keV stopping power. The source of neutrons for the 1239600100018 range of 4 to 7.5 MeV was the reaction D(d,n)He3, 1239600100019 which was produced by bombarding a deuterium gas 1239600100020 target about 300 to 100 keV thick. Neutrons emitted 1239600100021 in the forward direction were used from these 1239600100022 reactions, except for the energy interval of 40 to 1239600100023 120 keV where data were obtained at ll5 degrees from 1239600100024 the proton beam direction. 1239600100025 SAMPLE The samples of material which were used in this 1239600100026 simple transmission experiment were 1 in. diameter 1239600100027 cylinders of different lengths. The length of sample 1239600100028 used at a given energy was governed by the fact that 1239600100029 the greatest accuracy in cross section value is about 1239600100030 60%. 1239600100031 METHOD (TRN) Data for measuring total neutron cross sections 1239600100032 were obtained from a good geometry transmission 1239600100033 experiment in which samples were placed midway 1239600100034 between a neutron source and counter 20 in. apart. 1239600100035 ANALYSIS The cross sections were calculated in the usual way 1239600100036 by assuming that the transmission varied 1239600100037 exponentially with the thickness of the sample. 1239600100038 CORRECTION A correction for the neutron background caused by 1239600100039 neutrons scattered from the floor, etc., was obtained 1239600100040 by placing a paraffin or polyethylene shadow cone 1239600100041 between the source and counter. The correction was 1239600100042 only 1 to 3% above 400 keV. When the T(d,n) reaction 1239600100043 was used, an additional run was made with hydrogen in 1239600100044 the target to correct for extraneous neutron 1239600100045 background caused by deuterons striking places other 1239600100046 than the gaseous target. This amounted to less than a 1239600100047 3% correction in the total cross section in each 1239600100048 case. Small angle scattering from the sample into the 1239600100049 detector was not taken into account since so little 1239600100050 is known about this correction and since the 1239600100051 favorable geometry used in the experiment would make 1239600100052 the correction a small one. 1239600100053 HISTORY (19760804T) Translated from SCISRS. 1239600100054 (19820519A) Converted to reaction formalism. 1239600100055 (20081125U) Title added. 1239600100056 (20220210A) BP: Updated status, digitized data, added 1239600100057 natural uranium data, facility, incoming 1239600100058 source, method, sample, error analysis, 1239600100059 analysis and corrections. 1239600100060 ENDBIB 58 0 1239600100061 NOCOMMON 0 0 1239600100062 ENDSUBENT 61 0 1239600199999 SUBENT 12396002 20220210 14981239600200001 BIB 5 7 1239600200002 REACTION (92-U-235(N,TOT),,SIG) 1239600200003 DETECTOR (BF3) For energies below 200 keV, a boron trifluoride 1239600200004 proportional counter imbedded in paraffin was used. 1239600200005 ERR-ANALYS (DATA-ERR) In general, the statistical errors were 1239600200006 within 0.2 barn. 1239600200007 STATUS (CURVE) Fig. 2, page 11. 1239600200008 HISTORY (20220210A) BP: Replaced data. 1239600200009 ENDBIB 7 0 1239600200010 NOCOMMON 0 0 1239600200011 DATA 3 8 1239600200012 EN DATA DATA-ERR 1239600200013 MEV B B 1239600200014 4.132E-02 12.927 0.332 1239600200015 7.228E-02 12.525 0.132 1239600200016 7.366E-02 12.990 1239600200017 9.661E-02 12.225 1239600200018 9.991E-02 11.519 1239600200019 1.178E-01 11.723 1239600200020 1.264E-01 12.211 1239600200021 1.510E-01 11.510 1239600200022 ENDDATA 10 0 1239600200023 ENDSUBENT 22 0 1239600299999 SUBENT 12396003 20220210 14981239600300001 BIB 4 11 1239600300002 REACTION (92-U-235(N,TOT),,SIG) 1239600300003 DETECTOR (IOCH) For neutron energies above 250 keV, recoils in 1239600300004 a gas ionization chamber were counted. The gas 1239600300005 counter was filled with hydrogen at pressures up to 1239600300006 500 psi or helium at 700 psi. The helium-filled 1239600300007 chamber proved to be more useful because it could be 1239600300008 used from 400 to 750 keV without changing gas 1239600300009 pressure, while the hydrogen counters required 1239600300010 pressure reduction at low neutron energies. 1239600300011 STATUS (CURVE) Fig. 2, page 11. 1239600300012 HISTORY (20220210A) BP: Replaced data. 1239600300013 ENDBIB 11 0 1239600300014 NOCOMMON 0 0 1239600300015 DATA 2 51 1239600300016 EN DATA 1239600300017 MEV B 1239600300018 2.503E-01 8.918 1239600300019 2.550E-01 9.471 1239600300020 2.707E-01 10.026 1239600300021 3.416E-01 8.552 1239600300022 3.449E-01 8.752 1239600300023 4.032E-01 8.381 1239600300024 4.290E-01 8.361 1239600300025 5.237E-01 7.505 1239600300026 6.169E-01 7.886 1239600300027 7.694E-01 6.766 1239600300028 7.933E-01 6.855 1239600300029 8.624E-01 6.637 1239600300030 9.565E-01 6.530 1239600300031 1.175E+00 6.713 1239600300032 1.237E+00 6.847 1239600300033 1.358E+00 6.674 1239600300034 1.417E+00 6.321 1239600300035 1.505E+00 6.831 1239600300036 1.617E+00 6.966 1239600300037 1.688E+00 6.526 1239600300038 1.831E+00 6.904 1239600300039 1.927E+00 7.016 1239600300040 2.008E+00 7.039 1239600300041 2.272E+00 7.198 1239600300042 2.315E+00 7.641 1239600300043 2.440E+00 7.377 1239600300044 2.546E+00 7.047 1239600300045 2.565E+00 7.821 1239600300046 2.758E+00 7.779 1239600300047 2.847E+00 7.559 1239600300048 3.121E+00 7.893 1239600300049 3.187E+00 7.783 1239600300050 3.290E+00 7.563 1239600300051 3.497E+00 7.852 1239600300052 3.646E+00 7.677 1239600300053 3.841E+00 7.590 1239600300054 3.918E+00 7.834 1239600300055 3.954E+00 8.144 1239600300056 4.087E+00 7.548 1239600300057 4.344E+00 7.793 1239600300058 4.432E+00 7.970 1239600300059 4.486E+00 7.462 1239600300060 4.723E+00 7.530 1239600300061 5.938E+00 7.029 1239600300062 6.256E+00 6.898 1239600300063 6.523E+00 6.767 1239600300064 6.724E+00 6.923 1239600300065 6.943E+00 6.659 1239600300066 7.090E+00 6.549 1239600300067 7.549E+00 6.374 1239600300068 7.711E+00 6.198 1239600300069 ENDDATA 53 0 1239600300070 ENDSUBENT 69 0 1239600399999 SUBENT 12396004 20220210 14981239600400001 BIB 4 6 1239600400002 REACTION (92-U-235(N,TOT),,SIG) 1239600400003 DETECTOR (SCIN) A stilbene scintillator using a 5819 1239600400004 photomultiplier tube served as the neutron counter 1239600400005 above 17 MeV. 1239600400006 STATUS (CURVE) Fig. 2, page 11. 1239600400007 HISTORY (20220210A) BP: Replaced data. 1239600400008 ENDBIB 6 0 1239600400009 NOCOMMON 0 0 1239600400010 DATA 2 3 1239600400011 EN DATA 1239600400012 MEV B 1239600400013 1.781E+01 5.981 1239600400014 1.915E+01 5.984 1239600400015 2.058E+01 6.008 1239600400016 ENDDATA 5 0 1239600400017 ENDSUBENT 16 0 1239600499999 SUBENT 12396005 20220210 14981239600500001 BIB 5 18 1239600500002 REACTION (94-PU-239(N,TOT),,SIG) 1239600500003 DETECTOR (IOCH,BF3,SCIN) Three types of neutron detectors were 1239600500004 employed. For neutron energies above 250 keV, recoils 1239600500005 in a gas ionization chamber were counted. The gas 1239600500006 counter was filled with hydrogen at pressures up to 1239600500007 500 psi or helium at 700 psi. The helium-filled 1239600500008 chamber proved to be more useful because it could be 1239600500009 used from 400 to 750 keV without changing gas 1239600500010 pressure, while the hydrogen counters required 1239600500011 pressure reduction at low neutron energies. For 1239600500012 energies below 200 keV, a boron trifluoride 1239600500013 proportional counter imbedded in paraffin was used. A 1239600500014 stilbene scintillator using a 5819 photomultiplier 1239600500015 tube served as the neutron counter above 17 MeV. 1239600500016 ERR-ANALYS (DATA-ERR) In general, the statistical errors were 1239600500017 within 0.2 barn. 1239600500018 STATUS (CURVE) Fig. 3, page 12. 1239600500019 HISTORY (20220210A) BP: Replaced data. 1239600500020 ENDBIB 18 0 1239600500021 NOCOMMON 0 0 1239600500022 DATA 3 50 1239600500023 EN DATA DATA-ERR 1239600500024 MEV B B 1239600500025 4.057E-02 14.274 0.541 1239600500026 6.898E-02 13.128 1239600500027 7.018E-02 12.527 0.280 1239600500028 9.455E-02 11.904 1239600500029 1.130E-01 12.243 1239600500030 1.196E-01 12.503 1239600500031 1.469E-01 12.161 1239600500032 2.493E-01 10.214 1239600500033 2.682E-01 9.573 1239600500034 3.421E-01 9.511 1239600500035 4.196E-01 8.808 1239600500036 4.443E-01 9.208 1239600500037 5.549E-01 8.225 1239600500038 6.563E-01 7.923 1239600500039 7.550E-01 7.802 1239600500040 8.517E-01 7.321 1239600500041 9.267E-01 7.380 1239600500042 1.047E+00 7.379 1239600500043 1.138E+00 7.218 1239600500044 1.226E+00 6.997 1239600500045 1.334E+00 7.137 1239600500046 1.424E+00 6.956 1239600500047 1.520E+00 6.856 1239600500048 1.670E+00 7.155 1239600500049 1.749E+00 6.955 1239600500050 1.869E+00 7.195 1239600500051 1.887E+00 7.395 1239600500052 2.192E+00 7.334 1239600500053 2.213E+00 7.474 1239600500054 2.298E+00 7.574 1239600500055 2.477E+00 7.553 1239600500056 2.595E+00 7.453 1239600500057 2.747E+00 7.833 1239600500058 2.853E+00 7.953 1239600500059 3.045E+00 7.772 1239600500060 3.163E+00 8.072 1239600500061 3.374E+00 7.671 1239600500062 3.376E+00 7.912 1239600500063 5.000E+00 7.729 1239600500064 5.238E+00 7.628 1239600500065 5.540E+00 7.548 1239600500066 5.860E+00 7.547 1239600500067 6.192E+00 7.106 1239600500068 6.194E+00 7.266 1239600500069 6.797E+00 6.965 1239600500070 7.258E+00 6.965 1239600500071 7.460E+00 6.744 1239600500072 1.778E+01 5.836 1239600500073 1.900E+01 6.297 1239600500074 2.029E+01 6.236 1239600500075 ENDDATA 52 0 1239600500076 ENDSUBENT 75 0 1239600599999 SUBENT 12396006 20220304 14981239600600001 BIB 5 18 1239600600002 REACTION (92-U-0(N,TOT),,SIG) 1239600600003 DETECTOR (IOCH,BF3,SCIN) Three types of neutron detectors were 1239600600004 employed. For neutron energies above 250 keV, recoils 1239600600005 in a gas ionization chamber were counted. The gas 1239600600006 counter was filled with hydrogen at pressures up to 1239600600007 500 psi or helium at 700 psi. The helium-filled 1239600600008 chamber proved to be more useful because it could be 1239600600009 used from 400 to 750 keV without changing gas 1239600600010 pressure, while the hydrogen counters required 1239600600011 pressure reduction at low neutron energies. For 1239600600012 energies below 200 keV, a boron trifluoride 1239600600013 proportional counter imbedded in paraffin was used. A 1239600600014 stilbene scintillator using a 5819 photomultiplier 1239600600015 tube served as the neutron counter above 17 MeV. 1239600600016 ERR-ANALYS (DATA-ERR) In general, the statistical errors were 1239600600017 within 0.2 barn. 1239600600018 STATUS (CURVE) Fig. 1, page 10. 1239600600019 HISTORY (20220210C) BP 1239600600020 ENDBIB 18 0 1239600600021 NOCOMMON 0 0 1239600600022 DATA 3 56 1239600600023 EN DATA DATA-ERR 1239600600024 MEV B B 1239600600025 4.008E-02 12.906 0.647 1239600600026 7.014E-02 13.316 0.337 1239600600027 9.379E-02 11.591 1239600600028 1.175E-01 11.931 1239600600029 1.190E-01 11.715 1239600600030 1.470E-01 11.213 1239600600031 2.162E-01 10.396 1239600600032 2.489E-01 9.987 1239600600033 2.606E-01 9.259 1239600600034 3.359E-01 8.963 1239600600035 4.104E-01 9.022 1239600600036 4.289E-01 8.836 1239600600037 6.598E-01 7.721 1239600600038 7.528E-01 7.330 1239600600039 8.814E-01 7.090 1239600600040 9.535E-01 7.054 1239600600041 9.706E-01 6.923 1239600600042 1.126E+00 6.869 1239600600043 1.218E+00 6.833 1239600600044 1.283E+00 6.834 1239600600045 1.400E+00 6.891 1239600600046 1.501E+00 6.892 1239600600047 1.582E+00 6.893 1239600600048 1.652E+00 6.950 1239600600049 1.710E+00 7.025 1239600600050 1.803E+00 6.914 1239600600051 1.899E+00 7.027 1239600600052 2.018E+00 7.140 1239600600053 2.126E+00 7.122 1239600600054 2.220E+00 7.291 1239600600055 2.318E+00 7.497 1239600600056 2.485E+00 7.461 1239600600057 2.642E+00 7.424 1239600600058 2.757E+00 7.799 1239600600059 2.881E+00 7.668 1239600600060 3.008E+00 7.744 1239600600061 3.143E+00 7.651 1239600600062 3.169E+00 7.838 1239600600063 3.195E+00 8.006 1239600600064 3.398E+00 7.802 1239600600065 3.425E+00 8.082 1239600600066 3.426E+00 7.970 1239600600067 3.522E+00 7.559 1239600600068 4.574E+00 7.582 1239600600069 4.948E+00 7.527 1239600600070 5.355E+00 7.397 1239600600071 5.403E+00 7.285 1239600600072 5.697E+00 7.080 1239600600073 6.004E+00 7.025 1239600600074 6.062E+00 6.745 1239600600075 6.386E+00 6.802 1239600600076 6.790E+00 6.691 1239600600077 7.095E+00 6.616 1239600600078 1.730E+01 6.050 1239600600079 1.888E+01 5.921 1239600600080 1.970E+01 6.202 1239600600081 ENDDATA 58 0 1239600600082 ENDSUBENT 81 0 1239600699999 ENDENTRY 6 0 1239699999999