ENTRY 14480 20170926 143814480 0 1 SUBENT 14480001 20170926 143814480 1 1 BIB 15 71 14480 1 2 TITLE Measurement of the 209Bi(n,4n)206Bi and 14480 1 3 169Tm(n,3n)167Tm cross sections between 23.5 and 30.5 14480 1 4 MeV relevant to reaction-in-flight neutron studies at 14480 1 5 the National Ignition Facility 14480 1 6 AUTHOR (M.E.Gooden,T.A.Bredeweg,B.Champine,D.C.Combs,S.Finch, 14480 1 7 A.Hayes-Sterbenz,E.Henry,Krishichayan,R.Rundberg, 14480 1 8 W.Tornow,J.Wilhelmy,C.Yeamans) 14480 1 9 INSTITUTE (1USALAS,1USAUCX,1USANCS,1USATNL,1USADKE,1USALRL) 14480 1 10 REFERENCE (J,PR/C,96,024622,2017) 14480 1 11 FACILITY (VDGT,1USATNL)The measurements were performed using 14480 1 12 the 10 MV FN tandem Van De Graaff accelerator at the 14480 1 13 Triangle Universities Nuclear Laboratory 14480 1 14 SAMPLE The bismuth targets were 0.9525mm in diameter and 1mm 14480 1 15 thick, while the thulium foils were the same diameter 14480 1 16 but 0.1 mm thick. The foils were stacked (Tm/Bi) and 14480 1 17 placed approx. 16 mm from the outer flange of the 14480 1 18 gas-cell assembly, with the thulium foil nearest the 14480 1 19 neutron production target. Following foils were used 14480 1 20 in measurement 14480 1 21 Energy (MeV) Bi(mg) Tm(mg) 14480 1 22 23.5+-0.105 0.7393 0.0681 14480 1 23 24.9+-0.130 0.7436 0.0680 14480 1 24 25.6+-0.133 0.7355 0.0670 14480 1 25 26.5+-0.138 0.7416 0.0684 14480 1 26 27.5+-0.142 0.7386 0.0688 14480 1 27 28.5+-0.147 0.7393 0.0683 14480 1 28 29.5+-0.156 0.6833 0.0695 14480 1 29 30.5+-0.165 0.6833 0.0684 14480 1 30 DETECTOR (HPGE)After irradiation, the foils were mounted in 14480 1 31 front of lead-shielded high-purity germanium (HPGe) 14480 1 32 detectors for gamma-ray counting for approx. 24 h. The 14480 1 33 bismuth foils were counted at 2.5 cm from the face of 14480 1 34 one HPGe detector, while the Tm foils were counted at 14480 1 35 5 cm on a separate, but nearly identical, HPGe 14480 1 36 detector. 14480 1 37 (HPGE)Due to the long half-life of the reference 14480 1 38 reaction used (31.55 yr), the bismuth samples were 14480 1 39 returned to LANL and counted on the Compton 14480 1 40 suppressed dual-clover HPGe detector system, which 14480 1 41 has significantly higher efficiency than the other 14480 1 42 HPGe detectors. 14480 1 43 METHOD (ACTIV) 14480 1 44 MONITOR (83-BI-209(N,3N)83-BI-207,,SIG) 14480 1 45 DECAY-MON (83-BI-207,31.55YR) 14480 1 46 MONIT-REF (,E.M.Zsolnay+,R,INDC(NDS)-0616,2012) 14480 1 47 (,K.I.Zolotarev,R,INDC(NDS)-0584,2010) 14480 1 48 INC-SOURCE (D-T) Quasimonoenergetic neutrons were produced with 14480 1 49 the 3H(d,n)4He reaction. Accelerated deuterons were 14480 1 50 incident onto a neutron production target consisting 14480 1 51 of 2.1 Ci tritium absorbed onto a 19 mm diameter 14480 1 52 deposit of titanium on a 0.4 mm thick Cu backing. 14480 1 53 Neutron energy was measured using neutron 14480 1 54 time-of-flight. Neutron spectrum showed main peak and 14480 1 55 a group of low energy off-energy neutrons. 14480 1 56 CORRECTION Corrected for contribution of off-energy neutrons. 14480 1 57 Corrections ranged from 0.1% for 23 MeV neutrons and 14480 1 58 almost 50% for 30 MeV neutrons 14480 1 59 ERR-ANALYS (ERR-1,,0.02) Syst. uncertainty in target mass 14480 1 60 (ERR-2,0.1,3.5)Syst. uncertainty in peak area 14480 1 61 (ERR-3,1.19,1.42)Syst. uncertainty in gamma 14480 1 62 ray efficiency 14480 1 63 (ERR-4) Syst. uncertainty in neutron intensity 14480 1 64 fluctuation 14480 1 65 (ERR-5,3.,5.)Syst. uncertainty in Neutron monitor 14480 1 66 efficiency 14480 1 67 (ERR-6,0.1,3.8)Syst. uncertainty in gamma-ray emission 14480 1 68 probability 14480 1 69 (ERR-7,0.1,3.8)Syst. uncertainty in flux monitor cross 14480 1 70 sections 14480 1 71 (ERR-T) Total uncertainty at 1 sigma level 14480 1 72 HISTORY (20170926C) Compiled by S.H. 14480 1 73 ENDBIB 71 0 14480 1 74 COMMON 1 3 14480 1 75 ERR-4 14480 1 76 PER-CENT 14480 1 77 0.1 14480 1 78 ENDCOMMON 3 0 14480 1 79 ENDSUBENT 78 0 14480 199999 SUBENT 14480002 20170926 143814480 2 1 BIB 2 2 14480 2 2 REACTION (83-BI-209(N,4N)83-BI-206,,SIG) 14480 2 3 STATUS (TABLE) Data taken from tab. 4. of the reference 14480 2 4 ENDBIB 2 0 14480 2 5 NOCOMMON 0 0 14480 2 6 DATA 4 8 14480 2 7 EN EN-RSL DATA ERR-T 14480 2 8 MEV MEV B B 14480 2 9 23.9 0.105 0.00022 0.00002 14480 2 10 24.9 0.130 0.015 0.001 14480 2 11 25.5 0.133 0.047 0.004 14480 2 12 26.5 0.138 0.182 0.016 14480 2 13 27.5 0.142 0.438 0.041 14480 2 14 28.5 0.147 0.785 0.107 14480 2 15 29.5 0.156 0.826 0.095 14480 2 16 30.5 0.165 0.995 0.162 14480 2 17 ENDDATA 10 0 14480 2 18 ENDSUBENT 17 0 14480 299999 SUBENT 14480003 20170926 143814480 3 1 BIB 2 2 14480 3 2 REACTION (69-TM-169(N,3N)69-TM-167,,SIG) 14480 3 3 STATUS (TABLE) Data taken from tab. 4. of the reference 14480 3 4 ENDBIB 2 0 14480 3 5 NOCOMMON 0 0 14480 3 6 DATA 4 8 14480 3 7 EN EN-RSL DATA ERR-T 14480 3 8 MEV MEV B B 14480 3 9 23.9 0.105 1.78 0.12 14480 3 10 24.9 0.130 1.65 0.07 14480 3 11 25.5 0.133 1.73 0.08 14480 3 12 26.5 0.138 1.78 0.08 14480 3 13 27.5 0.142 1.86 0.09 14480 3 14 28.5 0.147 1.74 0.09 14480 3 15 29.5 0.156 1.21 0.08 14480 3 16 30.5 0.165 1.24 0.21 14480 3 17 ENDDATA 10 0 14480 3 18 ENDSUBENT 17 0 14480 399999 ENDENTRY 3 0 1448099999999