ENTRY 21194 20071219 21902119400000001 SUBENT 21194001 20071219 21902119400100001 BIB 15 42 2119400100002 INSTITUTE (2GERKFK) 2119400100003 REFERENCE (J,JNE,21,643,196708) 2119400100004 (J,PL,21,432,196606) 2119400100005 (R,EANDC(E)-74S,,196611) Conf rept. 2119400100006 (R,KFK-898,,196708) 2119400100007 (P,EANDC(E)-66U,7,196602) Abst. 2119400100008 AUTHOR (G.F.Knoll,W.P.Ponitz) 2119400100009 TITLE -A measurement of Th U-235 fission cross-section at 2119400100010 30 and 64 keV- 2119400100011 FACILITY (VDG) 3 MV Van de Graaff. 2119400100012 INC-SOURCE (P-LI7) Pulsed beam of protons bunched to 1 ns width 2119400100013 and collimated to 9 mm diameter incident on 2119400100014 thick Li-F target evaporated onto Cu backing 2119400100015 and coated with a layer of aluminium. Proton 2119400100016 energy 2 keV above threshold giving forward 2119400100017 collimated neutrons with mean energy 30 keV. 2119400100018 (P-T) 10 ns bursts of protons with energy of 4 keV 2119400100019 above P-t threshold incident on tritium to 2119400100020 generate kinematically collimated neutrons 2119400100021 with a mean energy of 64 keV. 2119400100022 SAMPLE .23.63+-0.03 mg U3-O8 (99.5 percent U-235) electro- 2119400100023 sprayed onto a 0.5 mm thick platinum backing. 2119400100024 .Effective thickness of the sample 1.022 mg/cm-sq. 2119400100025 METHOD .Detection of fission fragments. 2119400100026 DETECTOR (SCIN) Gas scintillator viewed by 56 uvp photo- 2119400100027 multiplier to detect fission fragments. 2119400100028 (NAICR) 4 X 3 inch NaI(Tl) crystal to measure gamma 2119400100029 activity of Li-F target after irradiation. 2119400100030 Same crystal to measure activity of gold 2119400100031 sample for normalisation. 2119400100032 MONITOR (79-AU-197(N,G)79-AU-198-G,,SIG) 2119400100033 PART-DET (FF) Fission fragments. 2119400100034 STATUS (NDD) From NEUDADA. 2119400100035 CORRECTION .Correction applied for losses of fission fragments 2119400100036 below the bias energy (25 MeV) and absorption in the 2119400100037 foil. 2119400100038 ERR-ANALYS .Complete breakdown of 26 sources of error in table 2119400100039 2 of the publication. 2119400100040 HISTORY (19791127T) 2119400100041 (19800110E) 2119400100042 (20071219A) Date is corrected 2119400100043 (20071219U) Last checking has been done. 2119400100044 ENDBIB 42 0 2119400100045 NOCOMMON 0 0 2119400100046 ENDSUBENT 45 0 2119400199999 SUBENT 21194002 20071219 21902119400200001 BIB 2 2 2119400200002 REACTION (92-U-235(N,F),,SIG) 2119400200003 STATUS .Data from text of publication. 2119400200004 ENDBIB 2 0 2119400200005 NOCOMMON 0 0 2119400200006 DATA 3 1 2119400200007 EN DATA DATA-ERR 2119400200008 KEV B B 2119400200009 3.E+01 2.162 6.8E-02 2119400200010 ENDDATA 3 0 2119400200011 ENDSUBENT 10 0 2119400299999 SUBENT 21194003 20071219 21902119400300001 BIB 2 4 2119400300002 REACTION (92-U-235(N,F),,SIG) 2119400300003 .Cross-section measured using Au-197 activation to 2119400300004 monitor the flux. 2119400300005 STATUS .Data from text of publication. 2119400300006 ENDBIB 4 0 2119400300007 COMMON 2 3 2119400300008 MONIT MONIT-ERR 2119400300009 MB MB 2119400300010 6.04E+02 2.5E+01 2119400300011 ENDCOMMON 3 0 2119400300012 DATA 3 1 2119400300013 EN DATA DATA-ERR 2119400300014 KEV B B 2119400300015 3.E+01 2.288 1.3E-01 2119400300016 ENDDATA 3 0 2119400300017 ENDSUBENT 16 0 2119400399999 SUBENT 21194004 20071219 21902119400400001 BIB 3 6 2119400400002 REACTION (92-U-235(N,F),,SIG,,,DERIV) 2119400400003 ANALYSIS .Weighted mean of the values obtained using different 2119400400004 flux monitors in this work. 2119400400005 STATUS .Data from text of publication. 2119400400006 (DEP,21194002) 2119400400007 (DEP,21194003) 2119400400008 ENDBIB 6 0 2119400400009 NOCOMMON 0 0 2119400400010 DATA 3 1 2119400400011 EN DATA DATA-ERR 2119400400012 KEV B B 2119400400013 3.E+01 2.19 6.E-02 2119400400014 ENDDATA 3 0 2119400400015 ENDSUBENT 14 0 2119400499999 SUBENT 21194005 20071219 21902119400500001 BIB 4 10 2119400500002 REACTION ((92-U-235(N,F),,SIG)// 2119400500003 (92-U-235(N,F),,SIG)) Ratio of cross-section at 2119400500004 64 keV to that at 30 keV, measured using Au-197(N,g) 2119400500005 as flux monitor. Ratio of Au-197(N,g) cross-section 2119400500006 at 30 keV to that at 64 keV taken from previous 2119400500007 literature, summarised in table 3 of JNE,21,643,6708. 2119400500008 MONITOR ((79-AU-197(N,G)79-AU-198,,SIG)// 2119400500009 (79-AU-197(N,G)79-AU-198,,SIG)) 2119400500010 MONIT-REF (,,J,JNE,21,643,196708) 2119400500011 STATUS .Data from text of publication. 2119400500012 ENDBIB 10 0 2119400500013 NOCOMMON 0 0 2119400500014 DATA 4 1 2119400500015 EN-NM EN-DN DATA DATA-ERR 2119400500016 KEV KEV NO-DIM NO-DIM 2119400500017 6.4E+01 3.E+01 8.13E-01 5.2E-02 2119400500018 ENDDATA 3 0 2119400500019 ENDSUBENT 18 0 2119400599999 SUBENT 21194006 20071219 21902119400600001 BIB 3 7 2119400600002 REACTION (92-U-235(N,F),,SIG,,,DERIV) 2119400600003 ANALYSIS .Cross-section at 64 keV calculated from weighted mean 2119400600004 of cross-sections measured by different methods in 2119400600005 this work, and ratio of cross-sections at 30 keV and 2119400600006 64 keV measured relative to Au-197(N,g) in this work. 2119400600007 STATUS .Data from text of publication. 2119400600008 (DEP,21194005) 2119400600009 ENDBIB 7 0 2119400600010 NOCOMMON 0 0 2119400600011 DATA 3 1 2119400600012 EN DATA DATA-ERR 2119400600013 KEV B B 2119400600014 6.4E+01 1.78 1.3E-01 2119400600015 ENDDATA 3 0 2119400600016 ENDSUBENT 15 0 2119400699999 ENDENTRY 6 0 2119499999999