ENTRY M0388 20161222 M086M038800000001 SUBENT M0388001 20161222 M086M038800100001 BIB 14 63 M038800100002 TITLE Absolute photofission cross section of Au-197, Pb-nat, M038800100003 Bi-209, Th-232, U-238, and U-235 nuclei by 69-MeV M038800100004 monochromatic and polarized photons. M038800100005 AUTHOR (J.B.Martins,E.L.Moreira,O.A.P.Tavares,J.L.Vieira, M038800100006 L.Casano,A.D'angelo,C.Schaerf,M.L.Terranova, M038800100007 D.Babusci,B.Girolami) M038800100008 INSTITUTE (2ITYFRA,3BZLRIO) M038800100009 REFERENCE (J,PR/C,44,354,1991) M038800100010 INC-SOURCE (LCS) Scattering of laser light by the highenergy M038800100011 electrons circulating in the storage ring ADONE - M038800100012 Compton backscattering. M038800100013 FACILITY (ESTRG,2ITYFRA) Frascati National Laboratories LADON. M038800100014 SAMPLE The target materials consisted of metal films of M038800100015 high-purity natural gold, about 1.4 mg/cm**2, lead, M038800100016 about 4.1 mg/cm**2, and bismuth, about 5.7 mg/cm**2, M038800100017 prepared by vacuum evaporation on about 3.5 cm x 3.5 M038800100018 cm thin foils 1.72 mg/cm**2 thick of mylar as M038800100019 supports, and the films of natural thorium, natural M038800100020 uranium and 93 % - enriched U-235 oxides produced by M038800100021 the "parlodion ignition" method on about 4 cm x 4 cm M038800100022 sheets of muscovite mica about 25 mg/cm**2 thick, M038800100023 which served as supports and/or detectors for M038800100024 fission fragments. M038800100025 METHOD (EXTB,SITA) M038800100026 DETECTOR (TRD) 100 micron thick MACROFOL N, BAYER AG, foils M038800100027 and mica foils. M038800100028 ANALYSIS The direct fission fragment track counting. M038800100029 CORRECTION To obtain the final values of the physical quantities M038800100030 and associated errors, the data have been treated M038800100031 taking into account the geometry of irradiation, M038800100032 statistics of track counting and efficiency, M038800100033 registration efficiency, energy absorption effects M038800100034 of fission fragments by thick-target samples Au, Pb, M038800100035 and Bi, and background. M038800100036 ERR-ANALYS (ERR-SYS) The systematic uncertainty. M038800100037 COMMENT Absolute cross section measurements for the M038800100038 photofission reactions of Au-197, Pb-nat., Bi-209, M038800100039 Th-232, U-238, and U-235 muclei have been performed M038800100040 at an incident photon energy of 69 MeV using M038800100041 monochromatic and fully polarized photon beams and M038800100042 dielectric fission-track detectors. Nuclear fissility M038800100043 values have been obtained and results are in M038800100044 agreement with those from other laboratories, M038800100045 although in some cases discrepancies are observed M038800100046 between one other. For nuclei in the region of M038800100047 actinides the fissility result is > 0.4, while for M038800100048 Au, Pb, and Bi nuclei it only is about 10**-3 - M038800100049 10**-2. results have been interpreted in terms of the M038800100050 primary levinger's quasideuteron nuclear M038800100051 photoabsorption followed by a mechanism of M038800100052 evaporation-fission competition for the excited M038800100053 nuclei. Shell effects have been taken into account, M038800100054 and they are clearly manifested when fissility is M038800100055 evaluated. The influence of photon polarization on M038800100056 photofission of U-238 also has been investigated, and M038800100057 results have shown isotropy in the fragment azimutal M038800100058 distribution. M038800100059 HISTORY (19971015C) Data were compiled at the Russia MSU SINP M038800100060 CDFE by V.Varlamov. M038800100061 (20161222A) Corrected by V.Varlamov: dates, STATUS, M038800100062 ERR-ANALYS, COMMON, REACTION, DATA, SUBENTs 003, M038800100063 004, 006, 007, 009, 010, 012, 013, 015, 016, 018, M038800100064 0.19 deleted becase no data for EXFOR, lowercase. M038800100065 ENDBIB 63 0 M038800100066 COMMON 2 3 M038800100067 EN-RSL-FW EN M038800100068 PER-CENT MEV M038800100069 9. 69. M038800100070 ENDCOMMON 3 0 M038800100071 ENDSUBENT 70 0 M038800199999 SUBENT M0388002 20161222 M086M038800200001 BIB 4 5 M038800200002 REACTION (79-AU-197(G,F),,SIG) M038800200003 ERR-ANALYS (ERR-S) Statistical errors are given. M038800200004 STATUS (TABLE) Data from Table 4. M038800200005 HISTORY (20161222A) Corrected by V.Varlamov: REACTION, M038800200006 STATUS, COMMON, ERR-S. M038800200007 ENDBIB 5 0 M038800200008 NOCOMMON 0 0 M038800200009 DATA 3 1 M038800200010 DATA ERR-S ERR-SYS M038800200011 MB MB PER-CENT M038800200012 2.4E-2 1.4E-2 30. M038800200013 ENDDATA 3 0 M038800200014 ENDSUBENT 13 0 M038800299999 NOSUBENT M0388003 20161222 M086M038800300001 NOSUBENT M0388004 20161222 M086M038800400001 SUBENT M0388005 20161222 M086M038800500001 BIB 4 5 M038800500002 REACTION (82-PB-0(G,F),,SIG) M038800500003 ERR-ANALYS (ERR-S) Statistical errors are given. M038800500004 STATUS (TABLE) Data from Table 4. M038800500005 HISTORY (20161222A) Corrected by V.Varlamov: REACTION, M038800500006 STATUS, COMMON, ERR-S. M038800500007 ENDBIB 5 0 M038800500008 NOCOMMON 0 0 M038800500009 DATA 3 1 M038800500010 DATA ERR-S ERR-SYS M038800500011 MB MB PER-CENT M038800500012 5.0E-2 2.0E-2 23. M038800500013 ENDDATA 3 0 M038800500014 ENDSUBENT 13 0 M038800599999 NOSUBENT M0388006 20161222 M086M038800600001 NOSUBENT M0388007 20161222 M086M038800700001 SUBENT M0388008 20161222 M086M038800800001 BIB 4 5 M038800800002 REACTION (83-BI-209(G,F),,SIG) M038800800003 ERR-ANALYS (ERR-S) Statistical errors are given. M038800800004 STATUS (TABLE) Data from Table 4. M038800800005 HISTORY (20161222A) Corrected by V.Varlamov: REACTION, M038800800006 STATUS, COMMON, ERR-S. M038800800007 ENDBIB 5 0 M038800800008 NOCOMMON 0 0 M038800800009 DATA 3 1 M038800800010 DATA ERR-S ERR-SYS M038800800011 MB MB PER-CENT M038800800012 8.E-2 3.E-2 23. M038800800013 ENDDATA 3 0 M038800800014 ENDSUBENT 13 0 M038800899999 NOSUBENT M0388009 20161222 M086M038800900001 NOSUBENT M0388010 20161222 M086M038801000001 SUBENT M0388011 20161222 M086M038801100001 BIB 4 5 M038801100002 REACTION (90-TH-232(G,F),,SIG) M038801100003 ERR-ANALYS (ERR-S) Statistical errors are given. M038801100004 STATUS (TABLE) Data from Table 4. M038801100005 HISTORY (20161222A) Corrected by V.Varlamov: REACTION, M038801100006 STATUS, COMMON, ERR-S. M038801100007 ENDBIB 5 0 M038801100008 NOCOMMON 0 0 M038801100009 DATA 3 1 M038801100010 DATA ERR-S ERR-SYS M038801100011 MB MB PER-CENT M038801100012 6. 1. 6. M038801100013 ENDDATA 3 0 M038801100014 ENDSUBENT 13 0 M038801199999 NOSUBENT M0388012 20161222 M086M038801200001 NOSUBENT M0388013 20161222 M086M038801300001 SUBENT M0388014 20161222 M086M038801400001 BIB 4 5 M038801400002 REACTION (92-U-235(G,F),,SIG) M038801400003 ERR-ANALYS (ERR-S) Statistical errors are given. M038801400004 STATUS (TABLE) Data from Table 4. M038801400005 HISTORY (20161222A) Corrected by V.Varlamov: REACTION, M038801400006 STATUS, COMMON, ERR-S. M038801400007 ENDBIB 5 0 M038801400008 NOCOMMON 0 0 M038801400009 DATA 3 1 M038801400010 DATA ERR-S ERR-SYS M038801400011 MB MB PER-CENT M038801400012 9. 2. 6. M038801400013 ENDDATA 3 0 M038801400014 ENDSUBENT 13 0 M038801499999 NOSUBENT M0388015 20161222 M086M038801500001 NOSUBENT M0388016 20161222 M086M038801600001 SUBENT M0388017 20161222 M086M038801700001 BIB 4 5 M038801700002 REACTION (92-U-238(G,F),,SIG) M038801700003 ERR-ANALYS (ERR-S) Statistical errors are given. M038801700004 STATUS (TABLE) Data from Table 4. M038801700005 HISTORY (20161222A) Corrected by V.Varlamov: REACTION, M038801700006 STATUS, COMMON, ERR-S. M038801700007 ENDBIB 5 0 M038801700008 NOCOMMON 0 0 M038801700009 DATA 3 1 M038801700010 DATA ERR-S ERR-SYS M038801700011 MB MB PER-CENT M038801700012 10. 1. 6. M038801700013 ENDDATA 3 0 M038801700014 ENDSUBENT 13 0 M038801799999 NOSUBENT M0388018 20161222 M086M038801800001 NOSUBENT M0388019 20161222 M086M038801900001 ENDENTRY 19 0 M038899999999