ENTRY 20893 20160907 22522089300000001 SUBENT 20893001 20160907 22522089300100001 BIB 17 60 2089300100002 TITLE Cross section for the Li-6(n,alpha)H-3 reaction 2089300100003 AUTHOR (J.F.Barry) 2089300100004 INSTITUTE (2UK ALD) Atomic Weapon Research Establishment, 2089300100005 Aldermaston, UK. 2089300100006 REFERENCE (C,66WASH,2,763,1966) Main reference, graph is given 2089300100007 FACILITY (ACCEL) Accelerator not specified - By compiler 2089300100008 REL-REF (I,,P.H.White,J,JNE/AB,19,325,1965) Description of 2089300100009 ionization chamber 2089300100010 METHOD (ASSOP) .Collection of reaction products. 2089300100011 DETECTOR (IOCH) Cylindrical ionization chambers containing 2089300100012 a thin flat foil of material for measurement. 2089300100013 (FISCH) Fission chamber for U-235 monitor analogous 2089300100014 for that of Lithium. 2089300100015 Fission and lithium counters were clamped together so 2089300100016 that foils were concentric and separated only by the 2089300100017 thickness of counter walls aprx. 0.1 cm. Counter runs 2089300100018 were repeated with that assembly rotated through 180 2089300100019 degree about the line perpendicular to the neutron 2089300100020 beam. 2089300100021 INC-SOURCE (P-LI7) Li-7(p,n)Be-7 reaction at angles 60 and 120 2089300100022 degree 2089300100023 MONITOR ((MONIT1)92-U-235(N,F),,SIG) 577 barns at 0.025 eV, 2089300100024 from Stehn et al, BNL 325 (1965). 2089300100025 ((MONIT2)3-LI-6(N,T)2-HE-4,,SIG) 950 barns at 0.025 eV,2089300100026 from absorption xsec of natural Li given in MONIT-REF 2089300100027 Count rates from Li-d were actually measured relative 2089300100028 to the rate from U-235 at 25, 67 and 100 keV. The xs 2089300100029 for U-235(N,F) at these energies are not given. The 2089300100030 above cross sections at 0.025 eV were used to make 2089300100031 the method independent of the mass of material in each2089300100032 sample, the mass of U-235 being known. 2089300100033 MONIT-REF (,J.R.Stehn+,R,BNL-325,196502) USAEC Report BNL 325, 2089300100034 Brookhaven National Laboratory, Febr. 1965 2089300100035 SAMPLE A Lithium fluoride foil of aprx. 0.1 milligram/cm2 2089300100036 thickness over a circular area of 8 cm2; 2089300100037 A U-235 foil of aprx. 0.3 milligram/cm2 over an area 2089300100038 of 8 cm2. 2089300100039 CORRECTION .Corrections were made for neutron attenuation and 2089300100040 scattering in counters, for the small anisotropy due 2089300100041 to center-of-mass motion, for background due to room 2089300100042 scattering, for alpha-particle and triton absorption 2089300100043 in foils. 2089300100044 INC-SPECT .EN-RSL. Energy resolution is half base of resolution 2089300100045 function. 2 keV energy uncertainty incorporated in 2089300100046 cross section error. 2089300100047 ERR-ANALYS (ERR-T) Total error given. 2089300100048 COMMENT .Err-analysis and data values obtained by private 2089300100049 communication. Though the cross sections were 2089300100050 determined independently of the mass of material 2089300100051 in each sample, as a check the mass of Li-6 was 2089300100052 determined by coulometric analysis. This gave a 2089300100053 consistent value for each cross section but with 2089300100054 greater error. 2089300100055 HISTORY (19790424C) 2089300100056 (19810127A) G.C., Error analysis changed. 2089300100057 (20111117U) BIB-information corrected. 2089300100058 (20111217A) New SUBENT added - SM 2089300100059 (20160907A) SD:Subent 009 deleted according 'NRDC 2014'2089300100060 Conclusion 30 ('Data sets derived by other than the 2089300100061 author are not for compilation...'). 2089300100062 ENDBIB 60 0 2089300100063 COMMON 3 3 2089300100064 EN-NRM MONIT1 MONIT2 2089300100065 EV B B 2089300100066 2.5E-02 5.77E+02 9.5E+02 2089300100067 ENDCOMMON 3 0 2089300100068 ENDSUBENT 67 0 2089300199999 SUBENT 20893002 20111117 22312089300200001 BIB 4 8 2089300200002 REACTION (3-LI-6(N,T)2-HE-4,,SIG) Equivalent to 2089300200003 (3-LI-6(N,A)1-H-3,,SIG) 2089300200004 REL-REF (A,20894003,S.E.Cox+,J,JNE,21,271,1967) The values 2089300200005 agree within the errors with those of Nucl.Energy, 2089300200006 21, 271,(1967). 2089300200007 STATUS (TABLE) .Data values obtained by private communication.2089300200008 HISTORY (20111117U) REL-REF keyword added 2089300200009 REACTION code explained 2089300200010 ENDBIB 8 0 2089300200011 NOCOMMON 0 0 2089300200012 DATA 4 3 2089300200013 EN EN-RSL DATA ERR-T 2089300200014 KEV KEV B B 2089300200015 2.5E+01 6. 1.09 7.E-02 2089300200016 6.7E+01 1.0E+01 8.10E-01 6.E-02 2089300200017 1.0E+02 1.3E+01 6.95E-01 2.E-03 2089300200018 ENDDATA 5 0 2089300200019 ENDSUBENT 18 0 2089300299999 NOSUBENT 20893003 20160907 22522089300300001 ENDENTRY 3 0 2089399999999