ENTRY 23391 20191113 22832339100000001 SUBENT 23391001 20191113 22832339100100001 BIB 12 55 2339100100002 TITLE 242Pu neutron-induced fission cross-section measurement2339100100003 from 1 to 2 MeV neutron energy 2339100100004 AUTHOR (P.Marini,L.Mathieu,M.Aiche,G.Belier,S.Czajkowski, 2339100100005 Q.Ducasse,B.Jurado,G.Kessedjian,J.Matarranz,A.Plompen, 2339100100006 P.Salvador-Castineira,J.Taieb,I.Tsekhanovich) 2339100100007 INSTITUTE (2FR GRA) P.Marini,L.Mathieu,M.Aiche,S.Czajkowski, 2339100100008 Q.Ducasse,B.Jurado,J.Matarranz,I.Tsekhanovich 2339100100009 (2FR BRC) P.Marini,G.Belier,J.Taieb 2339100100010 (2FR GRE) G.Kessedjian 2339100100011 (2ZZZGEL) A.Plompen,P.Salvador-Castineira 2339100100012 (2UK NPL) P.Salvador-Castineira 2339100100013 REFERENCE (J,PR/C,96,054604,2017) 2339100100014 #doi:10.1103/PhysRevC.96.054604 2339100100015 FACILITY (VDG,2FR BRC) 4 MV Van de Graaff accelerator 2339100100016 INC-SOURCE (P-T) 950 microgram/cm2 TiT solid target. 2339100100017 Proton beam 4microA. Neutron flux ~10**6 n/(cm2*sec) 2339100100018 Nominal energy Cooling system Average energy 2339100100019 1.1 MeV water 1.024 MeV 2339100100020 1.5 MeV water 1.434 MeV 2339100100021 2.0 MeV air 1.940 MeV 2339100100022 1.1 MeV air 1.022 MeV 2339100100023 SAMPLE Pu-242 sample : 2339100100024 Activity (MBq) 0.2472 +- 0.0007 2339100100025 Thickness (microgram/cm2) 239.5+-2.1 2339100100026 Diameter (mm) 29.95 +- 0.03 2339100100027 Mass (mg) 1.688 +- 0.015 2339100100028 Isotopic purity, % 99.96518+-0.00045 2339100100029 Production method Electrodeposition 2339100100030 Number of atoms was determined from alpha-activity 2339100100031 and half-life and the deposit area. 2339100100032 DECAY-DATA (94-PU-242,3.75E+5YR) (3.75+-0.02)*10**5 yr. 2339100100033 DETECTOR (PHVC) Two fission detectors, each consisting of two 2339100100034 40 x 40 mm2 solar cells. 2339100100035 (SI) The neutron flux was measured by a proton-recoil 2339100100036 detector consisted of P-rich radiator ( 4 micrometer 2339100100037 polypropylene PP foil) mounted on Ta frame and 50microm2339100100038 silicon detector. 2339100100039 METHOD (PHD) Pulse height discrimination for alphas from FF - 2339100100040 for Pu-242. 2339100100041 Pu242 spontaneous fission rate was measured without 2339100100042 neutron beam. 2339100100043 Spontaneous fission efficiency was measured to be 2339100100044 (58.8+-0.17(stat)+-0.41(syst)) % . 2339100100045 Distances, mm: 2339100100046 neutron source - fission sample 54.7+-0.5 2339100100047 fission sample - photovoltaic cell 5.4+-0.2 2339100100048 neutron source - PP 89.7+-0.6 2339100100049 PP - silicon detector collimator 78.8+-0.2 . 2339100100050 CORRECTION For dead time - ~ 1.% with negligible uncertainty. 2339100100051 For scattered neutrons. 2339100100052 For kinematics (+0.5 %) and 2339100100053 fission-fragment anisotropy effects (< 2.5%) . 2339100100054 HISTORY (20180410C) M.M. 2339100100055 (20191113A) SD: Data correction in Subents 002,003. 2339100100056 Small corrections in Subent 001. 2339100100057 ENDBIB 55 0 2339100100058 NOCOMMON 0 0 2339100100059 ENDSUBENT 58 0 2339100199999 SUBENT 23391002 20191113 22832339100200001 BIB 8 32 2339100200002 REACTION (94-PU-242(N,F),,SIG) 2339100200003 MONITOR ((MONIT)1-H-1(N,EL)1-H-1,,SIG) For neutron flux. 2339100200004 (94-PU-242(N,F),,SIG) 2339100200005 MONIT-REF (,,3,ENDF/B-VII.1,,2011) At 1.9 MeV 2339100200006 ANALYSIS CS was measured relative to np standard cs - see 2339100200007 formula (4) in PR/C,96,054604,2017 . 2339100200008 En,MeV Nnf/Np(stat,syst) EPSp/EPSf OMEGApp/OMEGApu2339100200009 1.024 3.922+-1.2 +-2.3 0.01465+-1.0 0.1066+-2.4 2339100200010 1.434 4.583+-1.7 +-3.0 0.01472+-1.0 0.1075+-2.4 2339100200011 1.940 6.100+-1.0 +-2.8 0.01466+-1.0 0.1033+-2.1 2339100200012 1.022 4.244+-1.3 +-1.8 0.01466+-1.0 0.1014+-2.1 2339100200013 errors +- in %, 2339100200014 En - average neutron energy , 2339100200015 Nnf - fission counts, 2339100200016 Np - proton counts, 2339100200017 EPSp - proton detection efficiency, 2339100200018 EPSf - fission detection efficiency, 2339100200019 OMEGApp - PP solid angle, 2339100200020 OMEGApu - Pu solid angle 2339100200021 ERR-ANALYS (ERR-S) Statistical uncertainty 2339100200022 (ERR-SYS) Total systematical uncertainty 2339100200023 COVARIANCE (COR,4.,4.) Correlation matrix for 4 measurements 2339100200024 1.024 MeV, 1.434 MeV, 1.940 MeV, 1.022 MeV 2339100200025 1. 0.63 0.44 0.67 2339100200026 0.63 1. 0.38 0.41 2339100200027 0.44 0.38 1. 0.54 2339100200028 0.67 0.41 0.54 1. 2339100200029 STATUS (TABLE) Table IX of Phys.Rev.C,96,054604,2017 2339100200030 (COREL,23391003) absolute determination of cr.sect. 2339100200031 HISTORY (20191113A) SD: Value: 1.353 b -> 1.354 b at 1.434 MeV 2339100200032 according to the Tbl IX. Reaction PU-242(n,f) added to 2339100200033 MONITOR. 2339100200034 ENDBIB 32 0 2339100200035 COMMON 1 3 2339100200036 MONIT-ERR 2339100200037 PER-CENT 2339100200038 0.2 2339100200039 ENDCOMMON 3 0 2339100200040 DATA 6 4 2339100200041 EN-MEAN EN-ERR DATA ERR-S ERR-SYS MONIT 2339100200042 MEV MEV B PER-CENT PER-CENT B 2339100200043 1.022 0.036 1.414 1.3 2.8 4.174 2339100200044 1.024 0.036 1.373 1.2 3.3 4.174 2339100200045 1.434 0.033 1.354 1.7 3.8 3.475 2339100200046 1.940 0.032 1.457 1.0 3.5 2.936 2339100200047 ENDDATA 6 0 2339100200048 ENDSUBENT 47 0 2339100299999 SUBENT 23391003 20191113 22832339100300001 BIB 7 25 2339100300002 REACTION (94-PU-242(N,F),,SIG) 2339100300003 MONITOR ((MONIT)1-H-1(N,EL)1-H-1,,SIG) For neutron flux. 2339100300004 ANALYSIS CS was determined by two assumption: 2339100300005 - PP foil has uniform thickness; 2339100300006 71.9+-0.6 cm2 foil was cut from the same sheet as PP 2339100300007 foil, measured number of H-1 atoms was determined (see 2339100300008 III C1 section) to be (3.23+-0.07)*10**19, for density 2339100300009 0.946 g/cm3, it corresponds to thickness 3.96+-0.08 2339100300010 microm of PP; 2339100300011 H-1 quantity was used to normalize CS at different 2339100300012 energies. 2339100300013 - absolute values of corrections to Np are correct. 2339100300014 ERR-ANALYS (ERR-S) Statistical uncertainty 2339100300015 (ERR-SYS) Total systematical uncertainty 2339100300016 COVARIANCE (COR,4.,4.) Correlation matrix for 4 measurements 2339100300017 1.024 MeV, 1.434 MeV, 1.940 MeV, 1.022 MeV 2339100300018 1. 0.73 0.60 0.78 2339100300019 0.73 1. 0.54 0.58 2339100300020 0.60 0.54 1. 0.69 2339100300021 0.78 0.58 0.69 1. 2339100300022 STATUS (TABLE) Table IX of Phys.Rev.C,96,054604,2017 2339100300023 (COREL,23391002) cr.sect. values normalized to the 2339100300024 ENDF-B/VII.1 cr.sect. at 1.9 MeV 2339100300025 HISTORY (20191113A) SD: Value: 5.373 b -> 1.375 b at 1.024 MeV 2339100300026 according to remark from Dr. O.Iwamoto (see Tbl.IX). 2339100300027 ENDBIB 25 0 2339100300028 COMMON 1 3 2339100300029 MONIT-ERR 2339100300030 PER-CENT 2339100300031 0.2 2339100300032 ENDCOMMON 3 0 2339100300033 DATA 6 4 2339100300034 EN-MEAN EN-ERR DATA ERR-S ERR-SYS MONIT 2339100300035 MEV MEV B PER-CENT PER-CENT B 2339100300036 1.022 0.036 1.415 1.3 3.6 4.174 2339100300037 1.024 0.036 1.375 1.2 4.1 4.174 2339100300038 1.434 0.033 1.355 1.7 4.5 3.475 2339100300039 1.940 0.032 1.459 1.0 4.2 2.936 2339100300040 ENDDATA 6 0 2339100300041 ENDSUBENT 40 0 2339100399999 ENDENTRY 3 0 2339199999999