ENTRY 31508 20011122 00003150800000001 SUBENT 31508001 20011122 00003150800100001 BIB 15 41 3150800100002 TITLE Fission Neutron Spectrum Average Cross-Section of the 3150800100003 54Fe(n,a)51Cr Reaction 3150800100004 REFERENCE (J,RCA,78,11,1997) 3150800100005 AUTHOR (P.M.SUAREZ,M.A.ARRIBERE,A.J.KESTELMAN,I.M.COHEN) 3150800100006 INSTITUTE (3ARGCAB) First three authors. 3150800100007 (3ARGARG) Last author: Gerencia de Area Radioisotopes 3150800100008 y Radiaciones (CNEA) 3150800100009 FACILITY (REAC,3ARGCAB) RA-6 Research Reactor at Centro 3150800100010 Atomico Bariloche: MTR-type, 95% enriched fuel 3150800100011 SAMPLE Three different samples were used: 3150800100012 - 0.229 mm diameter wire, 99.865% purity; 3150800100013 - rod chips, 99.98% purity; 3150800100014 - 2.0 mm thickness foil, 99.9985% purity. 3150800100015 The samples were irradiated inside 1 mm-thick 3150800100016 cadmium covers. 3150800100017 METHOD (ACTIV) The sample weres irradiated during 6 to 20 min 3150800100018 After a decay time of at least 2 days, a 24- to 45-h 3150800100019 gamma spectrum was collected for the measurement 3150800100020 of the Fe-54(n,a) reaction. 3150800100021 PART-DET (DG) 3150800100022 INC-SOURCE (REAC) Irradiations were performed in the reactor core 3150800100023 in undisturbed U-235 fission neutron spectrum; 3150800100024 approximate fast flux: 1.9*10E+12 n/(sec*cm2) 3150800100025 DECAY-DATA (25-MN-54,312.12D,DG,834.84,0.99976) 3150800100026 (24-CR-51,27.702D,DG,320.08,0.1008) 3150800100027 (27-CO-58,70.82D,DG,810.77,0.99449) 3150800100028 DETECTOR (HPGE) 63cm**3 ORTEC intrinsic-N coaxial detector 3150800100029 2.0 keV FWHM, 12.3% relative efficienty, dead time<2% 3150800100030 MONITOR (26-FE-54(N,P)25-MN-54,,SIG) 3150800100031 ERR-ANALYS Relative cross section measurements: 3150800100032 - systemaic uncertainty, ~2% 3150800100033 Absolute cross section measurements: 3150800100034 - systemaic uncertainty, 2% 3150800100035 - reference cross section, 2.8% 3150800100036 - absolute detection efficiency, 2% 3150800100037 - Cr-51,320keV gamma ray yield, 2% 3150800100038 - sample purity, 0.1% to 0.5% 3150800100039 - other contributions, 1% 3150800100040 STATUS Data taken from Radiochim.Acta 78,11(1997), 3150800100041 HISTORY (20001127C) VZ 3150800100042 (20010620U) OS. STATUS keyword added 3150800100043 ENDBIB 41 0 3150800100044 COMMON 1 3 3150800100045 EN-DUMMY 3150800100046 MEV 3150800100047 1.5 3150800100048 ENDCOMMON 3 0 3150800100049 ENDSUBENT 48 0 3150800199999 SUBENT 31508002 20001127 00003150800200001 BIB 2 4 3150800200002 REACTION 1((26-FE-54(N,A)24-CR-51,,SIG,,FIS)/ 3150800200003 (26-FE-54(N,P)25-MN-54,,SIG,,FIS)) 3150800200004 2(26-FE-54(N,A)24-CR-51,,SIG,,FIS) 3150800200005 MONITOR 2(26-FE-54(N,P)25-MN-54,,SIG,,FIS) 3150800200006 ENDBIB 4 0 3150800200007 NOCOMMON 0 0 3150800200008 DATA 6 1 3150800200009 DATA 1ERR-T 1DATA 2ERR-T 2MONIT 2MONIT-ERR 23150800200010 NO-DIM NO-DIM MB MB MB MB 3150800200011 0.01064 0.00042 0.869 0.042 81.7 2.2 3150800200012 ENDDATA 3 0 3150800200013 ENDSUBENT 12 0 3150800299999 SUBENT 31508003 20001127 00003150800300001 BIB 2 2 3150800300002 REACTION (26-FE-54(N,A)24-CR-51,,SIG,,FIS) 3150800300003 MONITOR (28-NI-58(N,P)27-CO-58,,SIG) 3150800300004 ENDBIB 2 0 3150800300005 NOCOMMON 0 0 3150800300006 DATA 4 1 3150800300007 DATA ERR-T MONIT MONIT-ERR 3150800300008 MB MB MB MB 3150800300009 0.872 0.043 111. 3. 3150800300010 ENDDATA 3 0 3150800300011 ENDSUBENT 10 0 3150800399999 ENDENTRY 3 0 3150899999999