ENTRY 10922 19841205 00001092200000001 SUBENT 10922001 19841205 00001092200100001 BIB 15 81 1092200100002 INSTITUTE (1USAANL) 1092200100003 REFERENCE (J,NSE,78,359,8108) 1092200100004 AUTHOR (D.L.SMITH,M.M.BRETSCHER,J.W.MEADOWS) 1092200100005 TITLE MEASUREMENT OF THE CROSS SECTION FOR THE 1092200100006 LI-7(N,N'-TRITIUM)HE-4 REACTION IN THE ENERGY RANGE 1092200100007 7-9 MEV 1092200100008 FACILITY (DYNAM) ARGONNE FAST NEUTRON GENERATOR FACILITY 1092200100009 INC-SOURCE (D-D) DEUTERONS ON DEUTERIUM GAS 1092200100010 SAMPLE THREE BATCHES OF DIFFERENT LI7/LI6 RATIOS USED. LITHIUM1092200100011 PREPARED AS DISKS AND PRESS-FITTED INTO ALUMINIUM 1092200100012 CANS. NO EXPERIMENTAL DIFFERENCES ENCOUNTED WITH 1092200100013 DIFFERING SAMPLE RATIOS. 1092200100014 DETECTOR (SCIN) LIQUID SCINTILLATOR USED TO COUNT TRITIUM 1092200100015 ACTIVITY. 1092200100016 (FISCH) METHANE FILLED PARALLEL PLATE FISSION CHAMBER 1092200100017 WITH U-238 DEPOSIT. 1092200100018 MONITOR (92-U-235(N,F),,SIG) FROM ENDF/B-IV. 1092200100019 2(92-U-238(N,F),,SIG) FROM ENDF/B-V. 1092200100020 STANDARD U-235 SOURCES USED TO CALIBRATE U-238 FISSION1092200100021 CHAMBER MEASUREMENTS. 1092200100022 ENERGY SCALE OF ACCELERATOR CALIBRATED BY OBSERVING THE1092200100023 THRESHOLDS FOR THE LI-7, B-11 AND AL-27 (P,N) 1092200100024 REACTIONS. 1092200100025 STANDARD TRITIUM SOURCES USED TO CALIBRATE LIQUID 1092200100026 SCINTILLATORS. 1092200100027 METHOD SAMPLES ATTACHED TO LOW MASS FISSION DETECTOR. TRITIUM 1092200100028 ACTIVITY DETERMINED USING STANDARD LIQUID 1092200100029 SCINTILLATION COUNTING TECHNIQUES. SEPERATE 1092200100030 EXPERIMENTS USED TO CHECK FOR TRITIUM ACTIVITY 1092200100031 DETERMINATION REPRODUCABILITY AND SERIOUS SYSTEMATIC 1092200100032 ERRORS OF MEASUREMENT TECHNIQUES. CONVERSION OF DATA 1092200100033 TO CROSS SECTIONS UTILIZED MONTE CARLO AND ANYLYTICAL 1092200100034 TECHNIQUES TAKING INTO ACCOUNT EFFECTS OF GEOMETRY, 1092200100035 NEUTRON SOURCE CHARACTERISTICS, ABSORPTION AND 1092200100036 MULTIPLE SCATTERING OF NEUTRONS, TARGET THICKNESS, 1092200100037 TRITIUM HALF-LIFE, AND KINEMATICS. 1092200100038 CORRECTION CORRECTIONS MADE FOR- 1092200100039 -EFFECTS OF NEUTRON SCATTERING ON SAMPLE YIELDS, 1092200100040 APPROXIMATELY 3-PERCENT 1092200100041 -EFFECTS OF NEUTRON SCATTERING ON FISSION YIELDS, 1092200100042 APPROXIMATELY 6-PERCENT 1092200100043 -EMPTY CELL BACKGROUND CONTRIBUTION TO FISSION YIELD, 1092200100044 6 TO 15 PERCENT 1092200100045 -TRITIUM PRODUCTION, LESS THAN 5-PERCENT 1092200100046 -TRITIATED WATER STANDARD, 10-PERCENT 1092200100047 ERR-ANALYS (ERR-T) TOTAL ERROR. ACCIDENTALLY SAME FOR RATIOS AND 1092200100048 CROSS SECTION (SEE ERR-6). 1092200100049 1(ERR-S) SOURCES OF RANDOM ERROR ARE- 1092200100050 -LITHIUM AND WATER SAMPLE WEIGHTS,NEGLIGIBLE. 1092200100051 -GEOMETRIC UNCERTAINTIES, 2.1-2.2 PERCENT. 1092200100052 -FISSION COUNTS STATISTICS, 0.5-0.8 PERCENT. 1092200100053 -FISSION FROM BACKGROUND NEUTRONS, 0.5-1.7 PERCENT. 1092200100054 -TRITIUM COUNTING, 0.7-4.2 PERCENT, LESS THAN 1092200100055 1-PERCENT FOR ALL POINTS BUT ONE. 1092200100056 -HYDROGEN RECOVERY, 0.4-1.0 PERCENT. 1092200100057 -TRITIUM ACTIVITY REPRODUCIBILITY, 4.0-PERCENT 1092200100058 -TRITIUM FROM BACKGROUND NEUTRONS, LESS THAN 1092200100059 2.1-PERCENT 1092200100060 (ERR-1) CONSISTS OF UNCERTAINTIES DUE TO- 1092200100061 -COMPARISON OF U-238 AND U-235 1092200100062 -URANIUM DEPOSIT THICKNESS CORRECTION 1092200100063 -FISSION SPECTRUM EXTRAPOLATION 1092200100064 (ERR-2) CONSISTS OF UNCERTAINTIES DUE TO- 1092200100065 -TRITIUM HALF-LIFE 1092200100066 -NBS TRITIATED WATER STANDARD 1092200100067 (ERR-3) TRITIUM COUNTER CALIBRATION UNCERTAINTY 1092200100068 (ERR-4) CONSISTS OF UNCERTAINTIES DUE TO 1092200100069 -ENERGY SCALE 1092200100070 -NEUTRON TRANSMISSION AND SCATTERING 1092200100071 -NEUTRON SOURCE ANGULAR DISTRIBUTION 1092200100072 -NEUTRONS FROM D(D,P+N)D REACTION 1092200100073 (ERR-5) LI-6 CONTENT UNCERTAINTY 1092200100074 (ERR-6) U-238/U-235 FISSION CROSS SECTION RATIO 1092200100075 FOR RATIO = U-238/U-235 (N,F) RATIO UNCERTAINTY. 1092200100076 FOR CROSS SECTION = UNCERTAINTY IN U-235 FISSION 1092200100077 CROSS SECTION. 1092200100078 DECAY-DATA (1-H-3,12.346YR) 1092200100079 STATUS (APRVD) APPROVED BY J.W.MEADOWS 81/1/23. 1092200100080 HISTORY (801125C) 1092200100081 (811120A) UPDATED REFERENCE. 1092200100082 (841205A) BIB, DATA HEADING CORRECTIONS. 1092200100083 ENDBIB 81 0 1092200100084 NOCOMMON 0 0 1092200100085 ENDSUBENT 84 0 1092200199999 SUBENT 10922002 19841205 00001092200200001 BIB 1 2 1092200200002 REACTION 1((3-LI-7(N,N+T)2-HE-4,,SIG)/(92-U-238(N,F),,SIG)) 1092200200003 2(3-LI-7(N,N+T)2-HE-4,,SIG) 1092200200004 ENDBIB 2 0 1092200200005 COMMON 3 3 1092200200006 ERR-1 1ERR-2 1ERR-6 1 1092200200007 PER-CENT PER-CENT PER-CENT 1092200200008 2.0 0.6 2.0 1092200200009 ENDCOMMON 3 0 1092200200010 DATA 11 7 1092200200011 EN EN-RSL-FW DATA 1DATA 2ERR-3 1ERR-4 11092200200012 ERR-5 1ERR-S 1ERR-T MONIT1 MONIT2 2 1092200200013 MEV MEV NO-DIM MB PER-CENT PER-CENT 1092200200014 PER-CENT PER-CENT PER-CENT MB MB 1092200200015 6.89 0.141 0.4132 374. 1.1 1.6 1092200200016 4.6 5.8 906.1 1561. 1092200200017 7.86 0.155 0.3782 374. 1.1 2.0 1092200200018 4.7 6.0 989.9 1819. 1092200200019 7.86 0.155 0.3762 372. 1.1 2.0 1092200200020 4.7 6.0 989.9 1819. 1092200200021 8.85 0.178 0.3724 371. 1.1 2.3 1092200200022 0.3 5.3 6.6 997.3 1812. 1092200200023 8.86 0.176 0.3579 357. 1.1 2.3 1092200200024 5.3 6.6 997.4 1812. 1092200200025 8.87 0.178 0.3651 364. 1.1 2.3 1092200200026 5.1 6.6 997.5 1812. 1092200200027 8.96 0.181 0.3946 394. 0.8 2.3 1092200200028 6.4 7.4 998.1 1810. 1092200200029 ENDDATA 18 0 1092200200030 ENDSUBENT 29 0 1092200299999 ENDENTRY 2 0 1092299999999