ENTRY 14480 20170926 14381448000000001 SUBENT 14480001 20170926 14381448000100001 BIB 15 71 1448000100002 TITLE Measurement of the 209Bi(n,4n)206Bi and 1448000100003 169Tm(n,3n)167Tm cross sections between 23.5 and 30.5 1448000100004 MeV relevant to reaction-in-flight neutron studies at 1448000100005 the National Ignition Facility 1448000100006 AUTHOR (M.E.Gooden,T.A.Bredeweg,B.Champine,D.C.Combs,S.Finch, 1448000100007 A.Hayes-Sterbenz,E.Henry,Krishichayan,R.Rundberg, 1448000100008 W.Tornow,J.Wilhelmy,C.Yeamans) 1448000100009 INSTITUTE (1USALAS,1USAUCX,1USANCS,1USATNL,1USADKE,1USALRL) 1448000100010 REFERENCE (J,PR/C,96,024622,2017) 1448000100011 FACILITY (VDGT,1USATNL)The measurements were performed using 1448000100012 the 10 MV FN tandem Van De Graaff accelerator at the 1448000100013 Triangle Universities Nuclear Laboratory 1448000100014 SAMPLE The bismuth targets were 0.9525mm in diameter and 1mm 1448000100015 thick, while the thulium foils were the same diameter 1448000100016 but 0.1 mm thick. The foils were stacked (Tm/Bi) and 1448000100017 placed approx. 16 mm from the outer flange of the 1448000100018 gas-cell assembly, with the thulium foil nearest the 1448000100019 neutron production target. Following foils were used 1448000100020 in measurement 1448000100021 Energy (MeV) Bi(mg) Tm(mg) 1448000100022 23.5+-0.105 0.7393 0.0681 1448000100023 24.9+-0.130 0.7436 0.0680 1448000100024 25.6+-0.133 0.7355 0.0670 1448000100025 26.5+-0.138 0.7416 0.0684 1448000100026 27.5+-0.142 0.7386 0.0688 1448000100027 28.5+-0.147 0.7393 0.0683 1448000100028 29.5+-0.156 0.6833 0.0695 1448000100029 30.5+-0.165 0.6833 0.0684 1448000100030 DETECTOR (HPGE)After irradiation, the foils were mounted in 1448000100031 front of lead-shielded high-purity germanium (HPGe) 1448000100032 detectors for gamma-ray counting for approx. 24 h. The 1448000100033 bismuth foils were counted at 2.5 cm from the face of 1448000100034 one HPGe detector, while the Tm foils were counted at 1448000100035 5 cm on a separate, but nearly identical, HPGe 1448000100036 detector. 1448000100037 (HPGE)Due to the long half-life of the reference 1448000100038 reaction used (31.55 yr), the bismuth samples were 1448000100039 returned to LANL and counted on the Compton 1448000100040 suppressed dual-clover HPGe detector system, which 1448000100041 has significantly higher efficiency than the other 1448000100042 HPGe detectors. 1448000100043 METHOD (ACTIV) 1448000100044 MONITOR (83-BI-209(N,3N)83-BI-207,,SIG) 1448000100045 DECAY-MON (83-BI-207,31.55YR) 1448000100046 MONIT-REF (,E.M.Zsolnay+,R,INDC(NDS)-0616,2012) 1448000100047 (,K.I.Zolotarev,R,INDC(NDS)-0584,2010) 1448000100048 INC-SOURCE (D-T) Quasimonoenergetic neutrons were produced with 1448000100049 the 3H(d,n)4He reaction. Accelerated deuterons were 1448000100050 incident onto a neutron production target consisting 1448000100051 of 2.1 Ci tritium absorbed onto a 19 mm diameter 1448000100052 deposit of titanium on a 0.4 mm thick Cu backing. 1448000100053 Neutron energy was measured using neutron 1448000100054 time-of-flight. Neutron spectrum showed main peak and 1448000100055 a group of low energy off-energy neutrons. 1448000100056 CORRECTION Corrected for contribution of off-energy neutrons. 1448000100057 Corrections ranged from 0.1% for 23 MeV neutrons and 1448000100058 almost 50% for 30 MeV neutrons 1448000100059 ERR-ANALYS (ERR-1,,0.02) Syst. uncertainty in target mass 1448000100060 (ERR-2,0.1,3.5)Syst. uncertainty in peak area 1448000100061 (ERR-3,1.19,1.42)Syst. uncertainty in gamma 1448000100062 ray efficiency 1448000100063 (ERR-4) Syst. uncertainty in neutron intensity 1448000100064 fluctuation 1448000100065 (ERR-5,3.,5.)Syst. uncertainty in Neutron monitor 1448000100066 efficiency 1448000100067 (ERR-6,0.1,3.8)Syst. uncertainty in gamma-ray emission 1448000100068 probability 1448000100069 (ERR-7,0.1,3.8)Syst. uncertainty in flux monitor cross 1448000100070 sections 1448000100071 (ERR-T) Total uncertainty at 1 sigma level 1448000100072 HISTORY (20170926C) Compiled by S.H. 1448000100073 ENDBIB 71 0 1448000100074 COMMON 1 3 1448000100075 ERR-4 1448000100076 PER-CENT 1448000100077 0.1 1448000100078 ENDCOMMON 3 0 1448000100079 ENDSUBENT 78 0 1448000199999 SUBENT 14480002 20170926 14381448000200001 BIB 2 2 1448000200002 REACTION (83-BI-209(N,4N)83-BI-206,,SIG) 1448000200003 STATUS (TABLE) Data taken from tab. 4. of the reference 1448000200004 ENDBIB 2 0 1448000200005 NOCOMMON 0 0 1448000200006 DATA 4 8 1448000200007 EN EN-RSL DATA ERR-T 1448000200008 MEV MEV B B 1448000200009 23.9 0.105 0.00022 0.00002 1448000200010 24.9 0.130 0.015 0.001 1448000200011 25.5 0.133 0.047 0.004 1448000200012 26.5 0.138 0.182 0.016 1448000200013 27.5 0.142 0.438 0.041 1448000200014 28.5 0.147 0.785 0.107 1448000200015 29.5 0.156 0.826 0.095 1448000200016 30.5 0.165 0.995 0.162 1448000200017 ENDDATA 10 0 1448000200018 ENDSUBENT 17 0 1448000299999 SUBENT 14480003 20170926 14381448000300001 BIB 2 2 1448000300002 REACTION (69-TM-169(N,3N)69-TM-167,,SIG) 1448000300003 STATUS (TABLE) Data taken from tab. 4. of the reference 1448000300004 ENDBIB 2 0 1448000300005 NOCOMMON 0 0 1448000300006 DATA 4 8 1448000300007 EN EN-RSL DATA ERR-T 1448000300008 MEV MEV B B 1448000300009 23.9 0.105 1.78 0.12 1448000300010 24.9 0.130 1.65 0.07 1448000300011 25.5 0.133 1.73 0.08 1448000300012 26.5 0.138 1.78 0.08 1448000300013 27.5 0.142 1.86 0.09 1448000300014 28.5 0.147 1.74 0.09 1448000300015 29.5 0.156 1.21 0.08 1448000300016 30.5 0.165 1.24 0.21 1448000300017 ENDDATA 10 0 1448000300018 ENDSUBENT 17 0 1448000399999 ENDENTRY 3 0 1448099999999