ENTRY M0515 20230410 M124M0515 0 1 SUBENT M0515001 20230410 M124M0515 1 1 BIB 15 93 M0515 1 2 TITLE Photonuclear cross sections of Pu-239 using neutron M0515 1 3 capture gamma rays, near threshold. M0515 1 4 AUTHOR (M.Antonio,P.V.de Moraes,M.F.Cesar) M0515 1 5 REFERENCE (J,PS,47,519,1993) M0515 1 6 INSTITUTE (3BZLIPE) M0515 1 7 FACILITY (REAC,3BZLIPE) IEA-R1 reactor. M0515 1 8 REL-REF (O,M0406003,M.A.P.V.De Moraes+,J,NIM/A,277,467,1989) - M0515 1 9 data for Pu-239. M0515 1 10 INC-SOURCE (MPH=(16-S-32(N,G)16-S-33)) EG = 5.43 MeV M0515 1 11 (MPH=(22-TI-48(N,G)22-TI-49)) EG = 6.73 MeV M0515 1 12 (MPH=(25-MN-55(N,G)25-MN-56)) EG = 7.23 MeV M0515 1 13 (MPH=(82-PB-207(N,G)82-PB-208)) EG = 7.38 MeV M0515 1 14 (MPH=(26-FE-56(N,G)26-FE-57)) EG = 7.64 MeV M0515 1 15 (MPH=(13-AL-27(N,G)13-AL-28)) EG = 7.72 MeV M0515 1 16 (MPH=(30-ZN-63(N,G)30-ZN-64)) EG = 7.88 MeV M0515 1 17 (MPH=(29-CU-64(N,G)29-CU-65)) EG = 7.91 MeV M0515 1 18 (MPH=(28-NI-64(N,G)28-NI-65)) EG = 9.00 MeV M0515 1 19 (MPH=(24-CR-52(N,G)24-CR-53)) EG = 9.72 MeV M0515 1 20 CRITIQUE 28-Ni-64 should be instead of 28-Ni-84. M0515 1 21 DETECTOR (TRD) Photofission fragments were detected by fission M0515 1 22 track registration technique in MAKROFOL KG (8 micron)M0515 1 23 (HE3SP) Neutrons from (g,f) and (g,n) reactions were M0515 1 24 detected simultaneously with fission fragments by 4pi M0515 1 25 long-counter consisting of 60 He-3 detectors M0515 1 26 conventionally distributed inside a moderator M0515 1 27 material (polyethylene). M0515 1 28 METHOD (EXTB,SITA,FISCT) M0515 1 29 SAMPLE The Pu-239 samples contained 51.4 mg deposited in the M0515 1 30 form of PuO-2 on four titanium disks each with an M0515 1 31 active diameter of 40 mm was used: M0515 1 32 masses isotope isotopic percentage M0515 1 33 (mg) A (atoms/%) M0515 1 34 12.8 238 0.01 M0515 1 35 13.2 239 99.01 M0515 1 36 12.8 240 0.98 M0515 1 37 ANALYSIS The direct measurements of number of fission fragments M0515 1 38 using the scanning of the MAKROFOL sheets by means of M0515 1 39 conventional optical microscopy. M0515 1 40 The direct measurements of photoneutrons from a total M0515 1 41 neutron production reaction (g,n-tot) and M0515 1 42 photofission reaction (g,f) - sig (g,n-tot) = sig M0515 1 43 (g,n) + nu * sig (g,f), where nu(e) is the value of M0515 1 44 the prompt neutron multiplicity (the average number M0515 1 45 of prompt neutrons per fission). M0515 1 46 ERR-ANALYS (ERR-T) The total errors. M0515 1 47 (ERR-1) Systematic uncertainty in the photopeak M0515 1 48 efficiency determination - 10%. M0515 1 49 (ERR-2) Systematic error in the calibration for M0515 1 50 fission counting - 3%. M0515 1 51 (ERR-3) Systematic error in the calibration of neutron M0515 1 52 counting - 3.6%. M0515 1 53 (ERR-4) Systematic error from sample atom content - M0515 1 54 2.0%. M0515 1 55 COMMENT The error sources were: M0515 1 56 Gamma flux - 10% of the systematic uncertainty in the M0515 1 57 photopeak efficiency determination plus 1.5 to 3% of M0515 1 58 statistical error; photofission events - 3% of the M0515 1 59 systematic error in the calibration for fission M0515 1 60 counting plus 2 to 5% of the statistical uncertainty; M0515 1 61 photoneutron events - 3.6% of the systematic error in M0515 1 62 the calibration for neutron counting plus 6 to 10% of M0515 1 63 the statistical uncertainty; sample atom content - 2% M0515 1 64 of the systematic error. The experimental errors in M0515 1 65 nu(e) and in the relative intensity of the gamma-ray M0515 1 66 lines were not included in any error analysis. These M0515 1 67 values resulted in overall uncertainties of about 15% M0515 1 68 for the final photofission cross sections and about M0515 1 69 20% for the final total neutron cross sections. The M0515 1 70 overall uncertainties for the final photoneutron M0515 1 71 cross sections ranged from 20 to 60%. M0515 1 72 The photofission and photoneutron cross sections of M0515 1 73 Pu-239 have been measured by using monochromatic and M0515 1 74 discrete photons produced by thermal neutron capture M0515 1 75 gamma-rays in several targets placed at the core of M0515 1 76 the IAA-R1 reactor in the energy interval from 5.43 M0515 1 77 to 9.72 MeV. From the photofission cross sections M0515 1 78 obtained and according to the liquid drop model, the M0515 1 79 height of the simple fission barrier was determined - M0515 1 80 f.b. = 5.7 (0.2) MeV. The relative fissionability to M0515 1 81 U-238 was also determined and shown to be energy M0515 1 82 independent - f.r. = 3.32(0.41). The total M0515 1 83 photoabsorption cross sections were calculated as M0515 1 84 well as the photofission branching ratio or fission M0515 1 85 probability pf = 0.70 (0.06). M0515 1 86 HISTORY (19971208C) Data were compiled at the Russia MSU SINP M0515 1 87 CDFE by V.Varlamov. M0515 1 88 (20160205A) Corrected by V.Varlamov: dates, STATUS, M0515 1 89 ERR-ANALYS, COMMON, lowercase. M0515 1 90 (20220817A) Corrected by VV and SD: SUBENT 003 deleted M0515 1 91 because duplication with M0406003, REACTION in SUBENT M0515 1 92 004, STATUS. M0515 1 93 (20230410U) Corrected by V.Varlamov: typos in HISTORY M0515 1 94 line (20220817A) M0515 1 95 ENDBIB 93 0 M0515 1 96 COMMON 4 3 M0515 1 97 ERR-1 ERR-2 ERR-3 ERR-4 M0515 1 98 PER-CENT PER-CENT PER-CENT PER-CENT M0515 1 99 10.0 3.0 3.6 2.0 M0515 1 100 ENDCOMMON 3 0 M0515 1 101 ENDSUBENT 100 0 M0515 199999 SUBENT M0515002 20220817 M120M0515 2 1 BIB 3 9 M0515 2 2 REACTION (94-PU-239(G,ABS),,SIG) M0515 2 3 STATUS (TABLE) Data from Table II of M0515 2 4 Phys.Script.,47(1993)519. M0515 2 5 (DEP,M0515003) M0515 2 6 Cross section of (g,f) reaction. M0515 2 7 (DEP,M0515004) M0515 2 8 Cross section of (g,n) reaction. M0515 2 9 HISTORY (20160205A) Corrected by V.Varlamov: STATUS. M0515 2 10 (20220817A) Corrected by VV and SD: STATUS. M0515 2 11 ENDBIB 9 0 M0515 2 12 NOCOMMON 0 0 M0515 2 13 DATA 3 9 M0515 2 14 EN DATA ERR-T M0515 2 15 MEV MB MB M0515 2 16 6.73 33.5 9.2 M0515 2 17 7.23 41.0 8.0 M0515 2 18 7.38 45.6 10.7 M0515 2 19 7.64 57.1 12.2 M0515 2 20 7.72 58.4 10.3 M0515 2 21 7.88 58.1 11.9 M0515 2 22 7.91 47.3 13.8 M0515 2 23 9.00 124.0 17.7 M0515 2 24 9.72 211.8 54.8 M0515 2 25 ENDDATA 11 0 M0515 2 26 ENDSUBENT 25 0 M0515 299999 NOSUBENT M0515003 20220817 M120M0515 3 1 SUBENT M0515004 20220817 M120M0515 4 1 BIB 5 16 M0515 4 2 REACTION (94-PU-239(G,N)94-PU-238,,SIG,,,DERIV) M0515 4 3 ANALYSIS Cross section for photoneutron reaction SIG(g,n) was M0515 4 4 obtained from the neutron yield reaction cross M0515 4 5 section, photofission reaction SIG(g,f)cross section M0515 4 6 and nu: (g,xn) = SIG(g,n) + nu x SIG(g,f) M0515 4 7 REL-REF (R,,B.L.Berman+,J,PR/C,34,2201,1986) M0515 4 8 The data for nu(e) values. M0515 4 9 STATUS (TABLE) Data from Table II of M0515 4 10 Phys.Script.,47(1993)519. M0515 4 11 (DEP,M0515003) M0515 4 12 Cross section of (g,f) reaction. M0515 4 13 (DEP,M0515005) M0515 4 14 Cross section of (g,xn) reaction. M0515 4 15 HISTORY (20160205A) Corrected by V.Varlamov: REACTION, STATUS. M0515 4 16 (20220817A) Corrected by VV and SD: REACTION, M0515 4 17 ANALYSIS, STATUS. M0515 4 18 ENDBIB 16 0 M0515 4 19 NOCOMMON 0 0 M0515 4 20 DATA 3 9 M0515 4 21 EN DATA ERR-T M0515 4 22 MEV MB MB M0515 4 23 6.73 12.7 7.1 M0515 4 24 7.23 14.2 1.8 M0515 4 25 7.38 11.1 6.8 M0515 4 26 7.64 19.5 6.9 M0515 4 27 7.72 14.2 4.1 M0515 4 28 7.88 15.7 4.4 M0515 4 29 7.91 11.1 8.9 M0515 4 30 9.00 31.3 2.9 M0515 4 31 9.72 79.9 29.6 M0515 4 32 ENDDATA 11 0 M0515 4 33 ENDSUBENT 32 0 M0515 499999 SUBENT M0515005 20220817 M120M0515 5 1 BIB 3 5 M0515 5 2 REACTION (94-PU-239(G,X)0-NN-1,,SIG) M0515 5 3 STATUS (TABLE) Data from Table II of M0515 5 4 Phys.Script.,47(1993)519. M0515 5 5 HISTORY (20160205A) Corrected by V.Varlamov: REACTION, STATUS. M0515 5 6 (20220817A) Corrected by VV and SD: STATUS. M0515 5 7 ENDBIB 5 0 M0515 5 8 NOCOMMON 0 0 M0515 5 9 DATA 3 9 M0515 5 10 EN DATA ERR-T M0515 5 11 MEV MB MB M0515 5 12 6.73 74.6 13.4 M0515 5 13 7.23 96.4 20.8 M0515 5 14 7.38 117.8 19.0 M0515 5 15 7.64 137.4 23.5 M0515 5 16 7.72 153.5 23.6 M0515 5 17 7.88 150.7 28.2 M0515 5 18 7.91 126.5 24.4 M0515 5 19 9.00 344.8 53.1 M0515 5 20 9.72 543.1 117.5 M0515 5 21 ENDDATA 11 0 M0515 5 22 ENDSUBENT 21 0 M0515 599999 ENDENTRY 5 0 M051599999999