ENTRY 23112 20180830 22702311200000001 SUBENT 23112001 20180830 22702311200100001 BIB 13 67 2311200100002 TITLE Surrogate ratio methodology for the indirect 2311200100003 determination of neutron capture cross sections. 2311200100004 AUTHOR (B.L.Goldblum,S.G.Prussin,L.A.Bernstein,W.Younes, 2311200100005 M.Guttormsen,H.T.Nyhus) 2311200100006 INSTITUTE (2NOROSL) M.Guttormsen,H.T.Nyhus 2311200100007 (1USABRK) B.L.Goldblum,S.G.Prussin 2311200100008 (1USALRL) L.A.Bernstein,W.Younes 2311200100009 (2NOROSL) M.Guttormsen,H.T.Nyhus 2311200100010 REFERENCE (J,PR/C,81,054606,2010) 2311200100011 #doi:10.1103/PhysRevC.81.054606 2311200100012 Main reference. 2311200100013 FACILITY (CYCLO,2NOROSL) CACTUS array at the Oslo Cyclotron 2311200100014 Laboratory. 2311200100015 INC-SOURCE 45-MeV He-3 ion beam. Beam currents 2 nA. 2311200100016 REL-REF (I,,M.Guttormsen+,J,PR/C,68,064306,2003) 2311200100017 (I,,A.Schiller+,J,PR/C,63,021306,2001) 2311200100018 Ion beam details. 2311200100019 (I,,L.Henden+,J,NP/A,589,249,1995) 2311200100020 Details of response function of CACTUS array. 2311200100021 (M,,M.Guttormsen+,J,NIM/A,374,371,1996) 2311200100022 Details of extraction of particle-gamma coincidence 2311200100023 spectra. 2311200100024 SAMPLE Dy-161,162,163 targets were self-supporting and 2311200100025 isotopically enriched to approximately 95% in the 2311200100026 isotope of interest with thicknesses of 2311200100027 approximately 2 mg/cm**2. An 11-day experiment 2311200100028 on the Dy-164 target was carried out with 38-MeV He-3 2311200100029 ions at the Oslo Cyclotron Lab. The Dy-164 target, 2311200100030 enriched to approximately 98.5% in isotope of interest,2311200100031 was prepared as a self-supporting foil of approximately2311200100032 1.7 mg/cm**2 thickness. 2311200100033 METHOD (COINC) Particle-gamma coincidence. 2311200100034 (EDE) 2311200100035 SRM- surrogate reaction method. 2311200100036 DETECTOR (COIN,SILI,SI) CP were detected with eight particle 2311200100037 telescopes, each consisting of a front Si dE 2311200100038 detector and a back Si(Li) E detector with 2311200100039 thicknesses of 140 and 3000 microm, respectively, 2311200100040 placed at an angle of 45 degrees relative to the 2311200100041 beam direction.Intrinsic particle energy resolution was2311200100042 determined using Am-241 source to be 50 keV at 2311200100043 Ealpha=5.486MeV. 2311200100044 Average energy resolution of the particle detectors 2311200100045 200 keV over entire particle energy region. 2311200100046 (NAICR) Array of 28 NaI gamma-ray detectors, which 2311200100047 intercepted a solid angle of 15% of 4PI, surrounded 2311200100048 the target and particle detectors. FWHM of the detector2311200100049 output varied from 80 keV at alpha-ray energy of 2311200100050 1.33 MeV up to 250 keV at alpha-ray energy of 8 MeV. 2311200100051 COMMENT Of author Bethany Goldblum (28.09.2010, 07.10.2010): 2311200100052 "I don't recommend using the data in Fig.1a and Fig.2a,2311200100053 because the trend suggests that the gamma-ray energy 2311200100054 threshold removes contributions to decays from discrete2311200100055 states and thus improves the agreement of the surrogate2311200100056 measurement with the directly-measured work. 2311200100057 It does not make sense to include the data from Fig1(a)2311200100058 and 2(a) in the EXFOR database, because they do not 2311200100059 accurately reflect the physics. They were presented to 2311200100060 show the effect of the gamma-ray energy threshold on 2311200100061 the extracted cross section, but the contribution from 2311200100062 discrete states in Fig. 1(a) and 2(a) data skews the 2311200100063 result. The presentation in the manuscript was meant to2311200100064 be illustrative of this effect." 2311200100065 STATUS (TABLE) Request for the data was sent 24.09.2010. 2311200100066 Data were received form B.Golblum 28.09.2010. 2311200100067 HISTORY (20100901C) M.M. 2311200100068 (20180830U) SD: ERR-ANALYS was updated in Subent 002. 2311200100069 ENDBIB 67 0 2311200100070 NOCOMMON 0 0 2311200100071 ENDSUBENT 70 0 2311200199999 SUBENT 23112002 20180830 22702311200200001 BIB 9 40 2311200200002 REACTION (66-DY-161(N,G)66-DY-162,,SIG,,,DERIV) 2311200200003 Cross section extracted using the surrogate reaction 2311200200004 method (SRM) with similar compound nuclei pairs 2311200200005 relative to the evaluated cross section obtained from 2311200200006 ENDF/B-VII.0 as a function of neutron energy obtained 2311200200007 via the (He3,He3') inelastic reaction with a g-ray 2311200200008 energy threshold of 500 keV and 2 MeV. 2311200200009 MONITOR (66-DY-163(N,G)66-DY-164,,SIG) 2311200200010 MONIT-REF (,,3,ENDF/B-VII.0,,2006) 2311200200011 ANALYSIS (SURGT) The ratio of the number of particle-gamma 2311200200012 coincident events to produce two different compound 2311200200013 nuclei (in this case, Dy-162 and Dy-164) using the 2311200200014 same surrogate reaction,(He3,He3'),was determined. 2311200200015 Ratio was normalized at EA=7100 keV. To obtain the 2311200200016 Dy-161(n,gamma) cross section, the normalized ratio 2311200200017 data were multiplied by ENDF/B-VII.0 Dy-163(n,gamma) 2311200200018 cross section matched at excitation energy.Result was 2311200200019 then shifted into equivalent neutron energy by 2311200200020 subtracting the neutron separation Dy-162 compound 2311200200021 nucleus (Sn=8196.9 keV) from excitation energy. 2311200200022 ERR-ANALYS (ERR-T) Statistical and systematical errors 2311200200023 included: 2311200200024 * Uncertainty of unfolding of CACTUS detector response2311200200025 function. 2311200200026 * Uncertainty in energy identified as normalization 2311200200027 point for gamma-decay probability. 2311200200028 * Uncertainty in contributions to particle-gamma 2311200200029 spectra due to target contaminants. 2311200200030 (ERR-1,10.,20.)Uncertainty of monitor reaction c-s as 2311200200031 conservative estimate. 2311200200032 CORRECTION For CACTUS detector response function about 6 %. 2311200200033 STATUS (TABLE) Data were received from author B.Golblum 2311200200034 28.09.2010. 2311200200035 Data are given on Fig.1 of J,PR/C,81,054606,2010. 2311200200036 Data obtained by threshold of 2 MeV (Fig.1b) 2311200200037 COMMENT Of compiler. Data obtained by threshold of 500 keV 2311200200038 (Fig.1a) was not included in EXFOR according to 2311200200039 comment of author. See COMMENT in Subent 001. 2311200200040 HISTORY (20180830U) SD: ERR-ANALYS was updated: 2311200200041 ERR-T,22. ->ERR-T; MONIT-ERR,20. -> ERR-1,10.,20. 2311200200042 ENDBIB 40 0 2311200200043 COMMON 1 3 2311200200044 EN-ERR 2311200200045 KEV 2311200200046 120. 2311200200047 ENDCOMMON 3 0 2311200200048 DATA 3 4 2311200200049 EN DATA ERR-T 2311200200050 KEV B B 2311200200051 133. 0.49304124 0.10785844 2311200200052 253. 0.38276963 0.08448288 2311200200053 373. 0.30829658 0.06872559 2311200200054 493. 0.20557559 0.04571493 2311200200055 ENDDATA 6 0 2311200200056 ENDSUBENT 55 0 2311200299999 SUBENT 23112003 20101029 22232311200300001 BIB 7 32 2311200300002 REACTION (66-DY-161(N,G)66-DY-162,,SIG,,,DERIV) 2311200300003 Cross section extracted using the surrogate reaction 2311200300004 method (SRM) with similar compound nuclei pairs 2311200300005 relative to the evaluated cross section obtained from 2311200300006 ENDF/B-VII.0 as a function of neutron energy obtained 2311200300007 via the (He3,He3') inelastic reaction with a g-ray 2311200300008 energy threshold of 500 keV and 2MeV. 2311200300009 MONITOR (66-DY-160(N,G)66-DY-161,,SIG) 2311200300010 MONIT-REF (,,3,ENDF/B-VII.0,,2006) 2311200300011 ANALYSIS (SURGT) The ratio of the number of particle-gamma 2311200300012 coincident events to produce two different compound 2311200300013 nuclei (in this case, 162Dy and 164Dy) using the 2311200300014 same surrogate reaction,(He3,He3'),was determined. 2311200300015 Ratio was normalized at EA=7100 keV. To obtain the 2311200300016 Dy-161(n,gamma) cross section, the normalized ratio 2311200300017 data were multiplied by ENDF/B-VII.0 Dy-163(n,gamma) 2311200300018 cross section matched at excitation energy.Result was 2311200300019 then shifted into equivalent neutron energy by 2311200300020 subtracting the neutron separation Dy-162 compound 2311200300021 nucleus (Sn=8196.9 keV) citation energy. 2311200300022 Normalization parameter A was defined to be 2311200300023 0.95+-0.01 and 1.05+-0.01 (stat.uncertainty) 2311200300024 at EA=7010 keV for Eth= 500 keV and 2 MeV,respectively.2311200300025 ERR-ANALYS (ERR-T,81.) Statistical and systematical errors 2311200300026 included. 2311200300027 STATUS (TABLE) Data were received from author B.Golblum 2311200300028 28.09.2010. 2311200300029 Data are given on Fig.2 (open circles) of 2311200300030 J,PR/C,81,054606,2010. 2311200300031 COMMENT Of compiler. Data obtained by threshold of 500 keV 2311200300032 (Fig.2a) was not included in EXFOR according to 2311200300033 comment of author. See COMMENT in Subent 001. 2311200300034 ENDBIB 32 0 2311200300035 COMMON 1 3 2311200300036 EN-ERR 2311200300037 KEV 2311200300038 120. 2311200300039 ENDCOMMON 3 0 2311200300040 DATA 3 4 2311200300041 EN DATA ERR-T 2311200300042 KEV B B 2311200300043 203. 0.43665713 0.39687002 2311200300044 323. 0.31013652 0.26738016 2311200300045 443. 0.19725667 0.15268784 2311200300046 563. 0.13908642 0.09289092 2311200300047 ENDDATA 6 0 2311200300048 ENDSUBENT 47 0 2311200399999 SUBENT 23112004 20101029 22232311200400001 BIB 7 33 2311200400002 REACTION (66-DY-161(N,G)66-DY-162,,SIG,,,DERIV) 2311200400003 Cross section extracted using the surrogate reaction 2311200400004 method (SRM) with similar compound nuclei pairs 2311200400005 relative to the evaluated cross section obtained from 2311200400006 ENDF/B-VII.0 as a function of neutron energy obtained 2311200400007 via the (He3,He4) pickup reaction with a g-ray energy 2311200400008 threshold of 500 keV and 2MeV. 2311200400009 MONITOR (66-DY-160(N,G)66-DY-161,,SIG) 2311200400010 MONIT-REF (,,3,ENDF/B-VII.0,,2006) 2311200400011 ANALYSIS (SURGT) The ratio of the number of particle-gamma 2311200400012 coincident events to produce two different compound 2311200400013 nuclei (in this case, 162Dy and 164Dy) using the 2311200400014 same surrogate reaction,(He3,He3'),was determined. 2311200400015 Ratio was normalized at EA=7100 keV. To obtain the 2311200400016 Dy-161(n,gamma) cross section, the normalized ratio 2311200400017 data were multiplied by ENDF/B-VII.0 Dy-163(n,gamma) 2311200400018 cross section matched at excitation energy.Result was 2311200400019 then shifted into equivalent neutron energy by 2311200400020 subtracting the neutron separation Dy-162 compound 2311200400021 nucleus (Sn=8196.9 keV) citation energy. 2311200400022 Normalization parameter A was defined to be 2311200400023 1.06+-0.01 and 1.21+-0.01 (stat.uncertainty) 2311200400024 at EA=5700 keV for Eth= 500 keV and 2 MeV,respectively.2311200400025 FLAG (1.) Data obtained by threshold of 500 keV (Fig.2a). 2311200400026 (2.) Data obtained by threshold of 2 MeV (Fig.2b). 2311200400027 ERR-ANALYS (EN-ERR-DIG) Digitizing error of EN. 2311200400028 (ERR-DIG) Digitizing error of DATA 2311200400029 (ERR-T,67.) Statistical and systematical errors 2311200400030 included. 2311200400031 STATUS (TABLE) Data were received from author B.Golblum 2311200400032 28.09.2010. 2311200400033 Data are given on Fig.2 (solid squares) of 2311200400034 J,PR/C,81,054606,2010. 2311200400035 ENDBIB 33 0 2311200400036 COMMON 1 3 2311200400037 EN-ERR 2311200400038 KEV 2311200400039 120. 2311200400040 ENDCOMMON 3 0 2311200400041 DATA 4 8 2311200400042 EN DATA ERR-T FLAG 2311200400043 KEV B B NO-DIM 2311200400044 143. 0.19535937 0.04556044 1. 2311200400045 143. 0.45945982 0.33372328 2. 2311200400046 263. 0.12489438 0.02759823 1. 2311200400047 263. 0.32448524 0.22359907 2. 2311200400048 383. 0.08133402 0.01961466 1. 2311200400049 383. 0.20320475 0.09683589 2. 2311200400050 503. 0.05166291 0.01560497 1. 2311200400051 503. 0.15132389 0.06002936 2. 2311200400052 ENDDATA 10 0 2311200400053 ENDSUBENT 52 0 2311200499999 ENDENTRY 4 0 2311299999999