ENTRY 30975 20090916 31413097500000001 SUBENT 30975001 20090916 31413097500100001 BIB 14 36 3097500100002 TITLE Measurement of fast neutron induced fission cross 3097500100003 section of Th-232 relative to U-238 3097500100004 AUTHOR (R.P.Anand,K.N.Iyengar,N.N.Ajitanand) 3097500100005 INSTITUTE (3INDTRM) 3097500100006 REFERENCE (P,BARC-1297,1,1986) Abstract, table given 3097500100007 (C,85JAIPUR,2,350,198512) Similar ot BARC-1297 3097500100008 SAMPLE A sandwich of 100 mg/cm**2 thick thorium and depleted 3097500100009 uranium (99% U-238) discs with a 0.1mm thick Lexan 3097500100010 plastic in between. 3097500100011 MONITOR (92-U-238(N,F),,SIG) 3097500100012 MONIT-REF (,,R,INDC-36,198105) 3097500100013 FACILITY (VDG,3INDTRM) 3097500100014 INC-SOURCE (P-T) 3097500100015 DETECTOR (TRD) Lexan plastic 3097500100016 METHOD The lexan pieces were etched to reveal fission 3097500100017 tracks on both surfaces of the lexan. In counting 3097500100018 the tracks only those having diameters larger than 3097500100019 a background discriminating value were included. 3097500100020 From the ratio of track densities on both sides of 3097500100021 the lexan the ratio of neutron-induced fission 3097500100022 cross sections of Th-232 to U-238 was determined. 3097500100023 Using the U-238 cross sections from the monitor 3097500100024 reference the ratios were converted to Th-232 cross 3097500100025 sections. 3097500100026 The resulting Th-232 fission cross sections were avera-3097500100027 ged over the neutron-energy resolution (about 100 keV) 3097500100028 ERR-ANALYS (ERR-S) The statistical error of each measurement is 3097500100029 estimated to be about 10%. 3097500100030 STATUS (TABLE) Data are taken from Table 1 of 3097500100031 BARC-1297 (1986), p1. 3097500100032 HISTORY (19920220C) HW 3097500100033 (19920617U) HW, spelling error in bib section of subent3097500100034 oo1 corrected. 3097500100035 (20090912A) SD:Updated to new date formats,lower case. 3097500100036 COMMON section and code in err-analys were added 3097500100037 OS. BIB modifications 3097500100038 ENDBIB 36 0 3097500100039 COMMON 1 3 3097500100040 ERR-S 3097500100041 PER-CENT 3097500100042 10.0 3097500100043 ENDCOMMON 3 0 3097500100044 ENDSUBENT 43 0 3097500199999 SUBENT 30975002 20090916 31413097500200001 BIB 1 1 3097500200002 REACTION (90-TH-232(N,F),,SIG) 3097500200003 ENDBIB 1 0 3097500200004 NOCOMMON 0 0 3097500200005 DATA 2 7 3097500200006 EN DATA 3097500200007 MEV B 3097500200008 1.38 0.046 3097500200009 1.52 0.088 3097500200010 1.59 0.123 3097500200011 1.65 0.127 3097500200012 1.71 0.105 3097500200013 1.85 0.121 3097500200014 1.95 0.086 3097500200015 ENDDATA 9 0 3097500200016 ENDSUBENT 15 0 3097500299999 ENDENTRY 2 0 3097599999999