ENTRY 21435 20060809 21782143500000001 SUBENT 21435001 20060809 21782143500100001 BIB 14 38 2143500100002 INSTITUTE (2UK HAR) CHEMISTRY DIVISION. 2143500100003 REFERENCE (C,66PARIS,2,3,196610) MAIN REFERENCE,FINAL DATA GIVEN.2143500100004 (J,JIN,24,1493,1962) DATA SUPERSEDED. 2143500100005 AUTHOR (M.J.CABELL,L.J.SLEE) 2143500100006 TITLE -THE RATIO OF THERMAL NEUTRON CAPTURE TO FISSION FOR 2143500100007 U-235 -. 2143500100008 FACILITY (SPECM) MASS SPECTROMETER. 2143500100009 (REAC ) PLUTO REACTOR. 2143500100010 INC-SOURCE (REAC ) IRRADIATION IN THE FLUX SCANNING TUBE OF THE 2143500100011 B2 FUEL ELEMENT OF THE PLUTO REACTOR FOR 47 DAYS. 2143500100012 INC-SPECT .THE NEUTRON SPECTRUM IN PLUTO HAS A TEMPERATURE OF 2143500100013 106 DEGREES AND A LARGE EPITHERMAL COMPONENT RANGING 2143500100014 FROM 0.046 TO 0.066 FOR THE EPITHERMAL INDEX. 2143500100015 SAMPLE .SAMPLE WERE PREPARED BY MIXING 93 PERCENT ENRICHED 2143500100016 U-235 WITH 99.995 PERCENT ENRICHED U-238. ALIQUOTS 2143500100017 OF APPROX 100 MICRO-GM U-235 WERE DISPERSED IN ABOUT 2143500100018 10 MG MAGNESIUM OXIDE FOR IRRADIATION. 2143500100019 METHOD (ASEP ) ISOTOPIC MASS SEPERATION USING AN A.E.I. 2143500100020 TYPE M.S.5 MASS SPECTROMETER. 10 MICRO-G URANIUM 2143500100021 ON TUNGSTEN FILAMENT SURFACE IONISATION SOURCE. 2143500100022 ANALYSIS .ALPHA DERIVED FROM CHANGES IN ISOTOPIC COMPOSITION 2143500100023 OF URANIUM MIXTURES FROM NEUTRON CAPTURE 2143500100024 AND FISSION. 2143500100025 MONITOR (27-CO-59(N,G)27-CO-60,,SIG) 2143500100026 2200 M/SEC VALUE. 2143500100027 SEPERATE CO-59, SM-149 AND U-238 SAMPLE 2143500100028 MONITORS WERE USED TO DETERMINE NEUTRON FLUX, THE 2143500100029 SPECTRUM TEMPERATURE AND THE EPITHERMAL COMPONENT. 2143500100030 ERR-ANALYS .UNCERTAINTY IN THE DERIVED 2200 M/SEC VALUE ARE 2143500100031 FROM MASS SPECTROMETER STATISTICAL ERRORS (0.1 PC), 2143500100032 DETERMINATION OF SPECTRUM AVERAGE ALPHA (1.0 PC), 2143500100033 THIS IS THEN COMBINED WITH UNCERTAINTIES IN WESTCOTTS 2143500100034 G AND S FACTORS TO GIVE A TOTAL ABSOLUTE UNCERATAINTY 2143500100035 OF 0.0033 2143500100036 STATUS .FINAL DATA FROM PAGE 12, 66PARIS. 2143500100037 HISTORY (19800303C) 2143500100038 (19800318E) 2143500100039 (20060809A) DATE and reference code corrected 2143500100040 ENDBIB 38 0 2143500100041 COMMON 1 3 2143500100042 MONIT 2143500100043 B 2143500100044 3.7200E+01 2143500100045 ENDCOMMON 3 0 2143500100046 ENDSUBENT 45 0 2143500199999 SUBENT 21435002 20060809 21782143500200001 BIB 2 2 2143500200002 REACTION (92-U-235(N,ABS),,ALF) 2200 M/SEC VALUE. 2143500200003 STATUS .TEXT, PAGE 12 OF 66PARIS. 2143500200004 ENDBIB 2 0 2143500200005 NOCOMMON 0 0 2143500200006 NODATA 0 0 ALL POINTS ELIMINATED FROM SET 2143500200007 ENDSUBENT 6 0 2143500299999 ENDENTRY 2 0 2143599999999