ENTRY 14584 20191203 14631458400000001 SUBENT 14584001 20191203 14631458400100001 BIB 15 73 1458400100002 TITLE Improved Cumulative Fission Yield Measurements with 1458400100003 Fission Spectrum Neutrons on 238U 1458400100004 AUTHOR (B.D.Pierson,L.R.Greenwood,S.C.Stave,J.T.Burke, 1458400100005 S.W.Padgett, A.M.Prinke,J.M.Goda,J.A.Bounds, 1458400100006 D.K.Hayes,A.S.Tamashiro, R.S.Wittman,G.Slavik, 1458400100007 M.P.Dion,J.G.Burch,T.S.Palmer) 1458400100008 REFERENCE (J,NDS,163,249,2020) 1458400100009 #doi:10.1016/j.nds.2020.01.006 1458400100010 REL-REF (R,,D.A.Brown+,J,NDS,148,1,2018) ENDF/B-VIII.0 FY data.1458400100011 INSTITUTE (1USABNW,1USALRL,1USALAS,1USAORU,1USAORL) 1458400100012 (1USAUSA) Department of Homeland Security, Washington 1458400100013 D.C. 20528, USA 1458400100014 FACILITY (CRASS,1USALAS) The National Critical Experiments 1458400100015 Research Center (NCERC) Godiva IV critical assembly. 1458400100016 INC-SPECT The center of the Godiva critical assembly and 1458400100017 exposed to a single pulsed irradiation. 1458400100018 SAMPLE Two depleted uranium samples: 99.961+-0.002% 238U, 1458400100019 0.0385+-0.004% 235U, and 0.00031+-0.004% 234U from 1458400100020 Lawrence Livermore National Laboratory (LLNL) were 1458400100021 packed into separate quartz ampoules, affixed using 1458400100022 quartz wool packing, and heat-sealed. 1458400100023 (92-U-238,ENR=0.99961) 1458400100024 (92-U-235,ENR=0.000385) 1458400100025 (92-U-234,ENR=0.0000031) 1458400100026 DETECTOR (GE) Two 65% relative-efficiency, Mirion broad energy 1458400100027 germanium (BEGe) detectors were horizontally 1458400100028 opposed to one another and shrouded on four-sides by 1458400100029 a copper-lined open lead box. 1458400100030 METHOD (ACTIV) The quartz ampoules were loaded on top of the 1458400100031 witness foil package into an aluminum sample holder. 1458400100032 The sample holder was loaded into the center-line 1458400100033 hole of the Godiva critical assembly. The witness 1458400100034 foil package contained copper, gold, cobalt, iron, 1458400100035 and titanium wires. Activities observed in these 1458400100036 wires were used to estimate the total neutron 1458400100037 fluence-energy profile from the exposure. Following 1458400100038 the burst, the samples remained in the critical 1458400100039 assembly for several minutes while the radiation 1458400100040 field inside the critical assembly room decayed to 1458400100041 radiologically manageable levels. The samples were 1458400100042 hand-carried from the critical assembly building to 1458400100043 the radiation counting facility and counting 1458400100044 commenced 39.9 min post-irradiation. 1458400100045 ANALYSIS (DECAY) Data acquired from the experiment were parsed 1458400100046 into discrete integral spectra of varying length and 1458400100047 analyzed using Mirion's Genie2000R software. The peak 1458400100048 locations were classified as single peaks or 1458400100049 multiplets and fit accordingly using low-tail 1458400100050 Gaussian functions and a step background. Peak 1458400100051 locations from each spectrum were identified using 1458400100052 Mirion's Genie2000R Nuclide Identification algorithm, 1458400100053 an empirical confidence function that accounts for 1458400100054 each radionuclides half-life, branching ratio, and 1458400100055 corresponding gamma rays. 1458400100056 ERR-ANALYS (ERR-T) STAYSL PNNL software code propagates 1458400100057 uncertainties from the production cross-section 1458400100058 covariance matrices. Uncertainties at 1 sigma 1458400100059 considered. 1458400100060 (ERR-1) Gamma-ray branching ratio. 1458400100061 (ERR-2) Half-life. 1458400100062 (ERR-3) Efficiency. 1458400100063 (ERR-4) Self-shielding correction factor. 1458400100064 CORRECTION The ENDF/B-VIII.0 parent fission yield was used to 1458400100065 correct for the temporal shift in the total atom 1458400100066 concentration of the radio-analyte. The 238U-metal 1458400100067 samples were dense, high Z samples that strongly 1458400100068 attenuated gamma-rays emitted by fission products 1458400100069 generated in the sample. The gamma-ray self- 1458400100070 shielding correction function was derived from the 1458400100071 attenuation observed in several fission products 1458400100072 with gamma-lines spanning the low-energy region. 1458400100073 STATUS (TABLE) Table IV and V, page 258. 1458400100074 HISTORY (20191203C) BP 1458400100075 ENDBIB 73 0 1458400100076 COMMON 1 3 1458400100077 EN-DUMMY 1458400100078 MEV 1458400100079 2.86 1458400100080 ENDCOMMON 3 0 1458400100081 ENDSUBENT 80 0 1458400199999 SUBENT 14584002 20191203 14631458400200001 BIB 2 20 1458400200002 REACTION (92-U-238(N,F)ELEM/MASS,CUM,FY,,FIS) 1458400200003 DECAY-DATA ((1.)35-BR-84-G,1908.0SEC,DG,882.0) 1458400200004 ((2.)39-Y-93-G,36648.SEC,DG,267.0) 1458400200005 ((3.)39-Y-94,1122.SEC,DG,919.0) 1458400200006 ((4.)43-TC-104,1098.SEC,DG,358.0) 1458400200007 ((5.)50-SN-128-G,3544.SEC,DG,482.0) 1458400200008 ((6.)51-SB-129-G,15840.SEC,DG,813.0) 1458400200009 ((7.)51-SB-130-G,2370.SEC,DG,793.0) 1458400200010 ((8.)52-TE-131-M,119700.SEC,DG,774.0) 1458400200011 ((9.)53-I-133-G,74880.SEC,DG,530.0) 1458400200012 ((10.)53-I-134-G,3150.SEC,DG,847.0) 1458400200013 ((11.)53-I-135,23652.SEC,DG,1132.0) 1458400200014 ((12.)54-XE-138,844.8SEC,DG,846.0) 1458400200015 ((13.)56-BA-139,4984.SEC,DG,166.0) 1458400200016 ((14.)56-BA-141,1096.2SEC,DG,190.0) 1458400200017 ((15.)56-BA-142,636.SEC,DG,255.0) 1458400200018 ((16.)57-LA-142,5466.SEC,DG,641.0) 1458400200019 ((17.)58-CE-146,811.2SEC,DG,218.0) 1458400200020 ((18.)60-ND-149,6221.SEC,DG,211.0) Data were taken from1458400200021 Nudat 2.0 in 2011. 1458400200022 ENDBIB 20 0 1458400200023 NOCOMMON 0 0 1458400200024 DATA 10 18 1458400200025 ELEMENT MASS ISOMER DATA ERR-T ERR-1 1458400200026 ERR-2 ERR-3 ERR-4 DECAY-FLAG 1458400200027 NO-DIM NO-DIM NO-DIM PC/FIS PC/FIS PER-CENT 1458400200028 PER-CENT PER-CENT PER-CENT NO-DIM 1458400200029 35.0 84.0 0.0 0.875 0.089 7.451458400200030 0.2516 0.635 0.222 1. 1458400200031 39.0 93.0 4.62 0.77 15.11458400200032 0.7859 1.003 1.76 2. 1458400200033 39.0 94.0 5.08 0.49 0.911458400200034 0.9107 0.610 0.212 3. 1458400200035 43.0 104.0 4.84 0.35 3.371458400200036 1.63 2.061 0.914 4. 1458400200037 50.0 128.0 0.236 0.034 12.01458400200038 0.2370 0.782 0.522 5. 1458400200039 51.0 129.0 0. 0.644 0.063 2.31458400200040 0.2272 0.673 0.244 6. 1458400200041 51.0 130.0 0.0 0.479 0.043 5.01458400200042 2.025 0.681 0.252 7. 1458400200043 52.0 131.0 1.0 0.276 0.020 1.901458400200044 0.7519 0.688 0.260 8. 1458400200045 53.0 133.0 7.30 0.55 3.51458400200046 0.4808 0.753 0.446 9. 1458400200047 53.0 134.0 8.08 0.61 3.11458400200048 0.3810 0.656 0.233 10. 1458400200049 53.0 135.0 7.33 0.56 3.101458400200050 0.3044 0.520 0.171 11. 1458400200051 54.0 138.0 5.69 0.55 4.131458400200052 0.5682 0.795 0.630 12. 1458400200053 56.0 139.0 6.34 0.60 1.051458400200054 0.3371 3.149 6.90 13. 1458400200055 56.0 141.0 5.03 0.51 7.091458400200056 0.3831 0.701 1.29 14. 1458400200057 56.0 142.0 3.93 0.40 3.901458400200058 1.887 1.180 1.97 15. 1458400200059 57.0 142.0 4.99 0.36 1.051458400200060 0.5488 0.711 0.335 16. 1458400200061 58.0 146.0 3.25 0.35 5.771458400200062 0.9612 3.462 3.35 17. 1458400200063 60.0 149.0 1.66 0.15 5.561458400200064 0.0578 3.506 3.11 18. 1458400200065 ENDDATA 40 0 1458400200066 ENDSUBENT 65 0 1458400299999 ENDENTRY 2 0 1458499999999