ENTRY M0515 20230410 M051500000001 SUBENT M0515001 20230410 20231011 M051500100001 BIB 15 93 M051500100002 TITLE Photonuclear cross sections of Pu-239 using neutron M051500100003 capture gamma rays, near threshold. M051500100004 AUTHOR (M.Antonio,P.V.de Moraes,M.F.Cesar) M051500100005 REFERENCE (J,PS,47,519,1993) M051500100006 INSTITUTE (3BZLIPE) M051500100007 FACILITY (REAC,3BZLIPE) IEA-R1 reactor. M051500100008 REL-REF (O,M0406003,M.A.P.V.De Moraes+,J,NIM/A,277,467,1989) - M051500100009 data for Pu-239. M051500100010 INC-SOURCE (MPH=(16-S-32(N,G)16-S-33)) EG = 5.43 MeV M051500100011 (MPH=(22-TI-48(N,G)22-TI-49)) EG = 6.73 MeV M051500100012 (MPH=(25-MN-55(N,G)25-MN-56)) EG = 7.23 MeV M051500100013 (MPH=(82-PB-207(N,G)82-PB-208)) EG = 7.38 MeV M051500100014 (MPH=(26-FE-56(N,G)26-FE-57)) EG = 7.64 MeV M051500100015 (MPH=(13-AL-27(N,G)13-AL-28)) EG = 7.72 MeV M051500100016 (MPH=(30-ZN-63(N,G)30-ZN-64)) EG = 7.88 MeV M051500100017 (MPH=(29-CU-64(N,G)29-CU-65)) EG = 7.91 MeV M051500100018 (MPH=(28-NI-64(N,G)28-NI-65)) EG = 9.00 MeV M051500100019 (MPH=(24-CR-52(N,G)24-CR-53)) EG = 9.72 MeV M051500100020 CRITIQUE 28-Ni-64 should be instead of 28-Ni-84. M051500100021 DETECTOR (TRD) Photofission fragments were detected by fission M051500100022 track registration technique in MAKROFOL KG (8 micron)M051500100023 (HE3SP) Neutrons from (g,f) and (g,n) reactions were M051500100024 detected simultaneously with fission fragments by 4pi M051500100025 long-counter consisting of 60 He-3 detectors M051500100026 conventionally distributed inside a moderator M051500100027 material (polyethylene). M051500100028 METHOD (EXTB,SITA,FISCT) M051500100029 SAMPLE The Pu-239 samples contained 51.4 mg deposited in the M051500100030 form of PuO-2 on four titanium disks each with an M051500100031 active diameter of 40 mm was used: M051500100032 masses isotope isotopic percentage M051500100033 (mg) A (atoms/%) M051500100034 12.8 238 0.01 M051500100035 13.2 239 99.01 M051500100036 12.8 240 0.98 M051500100037 ANALYSIS The direct measurements of number of fission fragments M051500100038 using the scanning of the MAKROFOL sheets by means of M051500100039 conventional optical microscopy. M051500100040 The direct measurements of photoneutrons from a total M051500100041 neutron production reaction (g,n-tot) and M051500100042 photofission reaction (g,f) - sig (g,n-tot) = sig M051500100043 (g,n) + nu * sig (g,f), where nu(e) is the value of M051500100044 the prompt neutron multiplicity (the average number M051500100045 of prompt neutrons per fission). M051500100046 ERR-ANALYS (ERR-T) The total errors. M051500100047 (ERR-1) Systematic uncertainty in the photopeak M051500100048 efficiency determination - 10%. M051500100049 (ERR-2) Systematic error in the calibration for M051500100050 fission counting - 3%. M051500100051 (ERR-3) Systematic error in the calibration of neutron M051500100052 counting - 3.6%. M051500100053 (ERR-4) Systematic error from sample atom content - M051500100054 2.0%. M051500100055 COMMENT The error sources were: M051500100056 Gamma flux - 10% of the systematic uncertainty in the M051500100057 photopeak efficiency determination plus 1.5 to 3% of M051500100058 statistical error; photofission events - 3% of the M051500100059 systematic error in the calibration for fission M051500100060 counting plus 2 to 5% of the statistical uncertainty; M051500100061 photoneutron events - 3.6% of the systematic error in M051500100062 the calibration for neutron counting plus 6 to 10% of M051500100063 the statistical uncertainty; sample atom content - 2% M051500100064 of the systematic error. The experimental errors in M051500100065 nu(e) and in the relative intensity of the gamma-ray M051500100066 lines were not included in any error analysis. These M051500100067 values resulted in overall uncertainties of about 15% M051500100068 for the final photofission cross sections and about M051500100069 20% for the final total neutron cross sections. The M051500100070 overall uncertainties for the final photoneutron M051500100071 cross sections ranged from 20 to 60%. M051500100072 The photofission and photoneutron cross sections of M051500100073 Pu-239 have been measured by using monochromatic and M051500100074 discrete photons produced by thermal neutron capture M051500100075 gamma-rays in several targets placed at the core of M051500100076 the IAA-R1 reactor in the energy interval from 5.43 M051500100077 to 9.72 MeV. From the photofission cross sections M051500100078 obtained and according to the liquid drop model, the M051500100079 height of the simple fission barrier was determined - M051500100080 f.b. = 5.7 (0.2) MeV. The relative fissionability to M051500100081 U-238 was also determined and shown to be energy M051500100082 independent - f.r. = 3.32(0.41). The total M051500100083 photoabsorption cross sections were calculated as M051500100084 well as the photofission branching ratio or fission M051500100085 probability pf = 0.70 (0.06). M051500100086 HISTORY (19971208C) Data were compiled at the Russia MSU SINP M051500100087 CDFE by V.Varlamov. M051500100088 (20160205A) Corrected by V.Varlamov: dates, STATUS, M051500100089 ERR-ANALYS, COMMON, lowercase. M051500100090 (20220817A) Corrected by VV and SD: SUBENT 003 deleted M051500100091 because duplication with M0406003, REACTION in SUBENT M051500100092 004, STATUS. M051500100093 (20230410U) Corrected by V.Varlamov: typos in HISTORY M051500100094 line (20220817A) M051500100095 ENDBIB 93 0 M051500100096 COMMON 4 3 M051500100097 ERR-1 ERR-2 ERR-3 ERR-4 M051500100098 PER-CENT PER-CENT PER-CENT PER-CENT M051500100099 10.0 3.0 3.6 2.0 M051500100100 ENDCOMMON 3 0 M051500100101 ENDSUBENT 100 0 M051500199999 SUBENT M0515002 20220817 M120M051500200001 BIB 3 9 M051500200002 REACTION (94-PU-239(G,ABS),,SIG) M051500200003 STATUS (TABLE) Data from Table II of M051500200004 Phys.Script.,47(1993)519. M051500200005 (DEP,M0515003) M051500200006 Cross section of (g,f) reaction. M051500200007 (DEP,M0515004) M051500200008 Cross section of (g,n) reaction. M051500200009 HISTORY (20160205A) Corrected by V.Varlamov: STATUS. M051500200010 (20220817A) Corrected by VV and SD: STATUS. M051500200011 ENDBIB 9 0 M051500200012 NOCOMMON 0 0 M051500200013 DATA 3 9 M051500200014 EN DATA ERR-T M051500200015 MEV MB MB M051500200016 6.73 33.5 9.2 M051500200017 7.23 41.0 8.0 M051500200018 7.38 45.6 10.7 M051500200019 7.64 57.1 12.2 M051500200020 7.72 58.4 10.3 M051500200021 7.88 58.1 11.9 M051500200022 7.91 47.3 13.8 M051500200023 9.00 124.0 17.7 M051500200024 9.72 211.8 54.8 M051500200025 ENDDATA 11 0 M051500200026 ENDSUBENT 25 0 M051500299999 NOSUBENT M0515003 20220817 M120M051500300001 SUBENT M0515004 20220817 M120M051500400001 BIB 5 16 M051500400002 REACTION (94-PU-239(G,N)94-PU-238,,SIG,,,DERIV) M051500400003 ANALYSIS Cross section for photoneutron reaction SIG(g,n) was M051500400004 obtained from the neutron yield reaction cross M051500400005 section, photofission reaction SIG(g,f)cross section M051500400006 and nu: (g,xn) = SIG(g,n) + nu x SIG(g,f) M051500400007 REL-REF (R,,B.L.Berman+,J,PR/C,34,2201,1986) M051500400008 The data for nu(e) values. M051500400009 STATUS (TABLE) Data from Table II of M051500400010 Phys.Script.,47(1993)519. M051500400011 (DEP,M0515003) M051500400012 Cross section of (g,f) reaction. M051500400013 (DEP,M0515005) M051500400014 Cross section of (g,xn) reaction. M051500400015 HISTORY (20160205A) Corrected by V.Varlamov: REACTION, STATUS. M051500400016 (20220817A) Corrected by VV and SD: REACTION, M051500400017 ANALYSIS, STATUS. M051500400018 ENDBIB 16 0 M051500400019 NOCOMMON 0 0 M051500400020 DATA 3 9 M051500400021 EN DATA ERR-T M051500400022 MEV MB MB M051500400023 6.73 12.7 7.1 M051500400024 7.23 14.2 1.8 M051500400025 7.38 11.1 6.8 M051500400026 7.64 19.5 6.9 M051500400027 7.72 14.2 4.1 M051500400028 7.88 15.7 4.4 M051500400029 7.91 11.1 8.9 M051500400030 9.00 31.3 2.9 M051500400031 9.72 79.9 29.6 M051500400032 ENDDATA 11 0 M051500400033 ENDSUBENT 32 0 M051500499999 SUBENT M0515005 20220817 M120M051500500001 BIB 3 5 M051500500002 REACTION (94-PU-239(G,X)0-NN-1,,SIG) M051500500003 STATUS (TABLE) Data from Table II of M051500500004 Phys.Script.,47(1993)519. M051500500005 HISTORY (20160205A) Corrected by V.Varlamov: REACTION, STATUS. M051500500006 (20220817A) Corrected by VV and SD: STATUS. M051500500007 ENDBIB 5 0 M051500500008 NOCOMMON 0 0 M051500500009 DATA 3 9 M051500500010 EN DATA ERR-T M051500500011 MEV MB MB M051500500012 6.73 74.6 13.4 M051500500013 7.23 96.4 20.8 M051500500014 7.38 117.8 19.0 M051500500015 7.64 137.4 23.5 M051500500016 7.72 153.5 23.6 M051500500017 7.88 150.7 28.2 M051500500018 7.91 126.5 24.4 M051500500019 9.00 344.8 53.1 M051500500020 9.72 543.1 117.5 M051500500021 ENDDATA 11 0 M051500500022 ENDSUBENT 21 0 M051500599999 ENDENTRY 5 0 M051599999999