ENTRY 12679 20220210 14981267900000001 SUBENT 12679001 20220210 14981267900100001 BIB 11 42 1267900100002 TITLE Determination of the 14-MeV Li-7(n,n'a)T cross section 1267900100003 from sphere multiplication and transmission 1267900100004 measurements 1267900100005 AUTHOR (R.G.Thomas) 1267900100006 REFERENCE (R,LA-1697,1954) 1267900100007 INSTITUTE (1USALAS) 1267900100008 FACILITY (ACCEL,1USALAS) 1267900100009 METHOD (SHELT) The Sphere Multiplication Measurement: In 1267900100010 this measurement, the ratio M of sphere-on to 1267900100011 sphere-off counting rates of an external 1267900100012 flat-response long counter is obtained, the neutron 1267900100013 source being located at the sphere center. Sphere 1267900100014 Transmission Measurements: Offhand it would appear 1267900100015 possible to obtain cross sections by the subtraction 1267900100016 of reaction channels from a value of inelastic 1267900100017 derivable from a sphere transmission measurement. 1267900100018 However, with a light scattering material such as Li7 1267900100019 there is the complication that as a result of the 1267900100020 energy degradation in scattering, those neutrons 1267900100021 elastically scattered in backward directions cannot 1267900100022 be distinguished from those inelastically scattered 1267900100023 in forward directions after excitation of low levels. 1267900100024 Fortunately, most of the elastic scattering occurs 1267900100025 into the so-called forward diffraction cone. 1267900100026 DETECTOR (LONGC) 1267900100027 ANALYSIS By utilizing lithium spherical shell transmission and 1267900100028 multiplication measurements, the Li7(n,n'g) Li7 and 1267900100029 the He6-production cross sections, it is possible to 1267900100030 deduce that the 14-MeV Li7(n,n'a) T cross section. 1267900100031 ERR-ANALYS (DATA-ERR) Estimated uncertainty. 1267900100032 COMMENT Compiler's comment: The authors mention always only 1267900100033 "14 MeV neutrons" without giving details of the 1267900100034 incident energy spectrum. It is quite likely that these1267900100035 "14 MeV neutrons" have an energy like 14.5 MeV or so 1267900100036 as it is very usual with T(d,n) neutrons. Therefore it 1267900100037 is probably better to give just a value of 14. 1267900100038 HISTORY (19841102C) 1267900100039 (20220210A) BP: Updated to new date formats,lower 1267900100040 case. corrections according last EXFOR rules and 1267900100041 Dict. Updated error analysis and method, added status, 1267900100042 analysis and facility, corrected energy from 14.7 to 141267900100043 MeV. 1267900100044 ENDBIB 42 0 1267900100045 NOCOMMON 0 0 1267900100046 ENDSUBENT 45 0 1267900199999 SUBENT 12679002 20220210 14981267900200001 BIB 2 2 1267900200002 REACTION (3-LI-7(N,N+T)2-HE-4,,SIG) 1267900200003 STATUS (TABLE) page 11. 1267900200004 ENDBIB 2 0 1267900200005 NOCOMMON 0 0 1267900200006 DATA 3 1 1267900200007 EN DATA DATA-ERR 1267900200008 MEV MB MB 1267900200009 14. 325. 75. 1267900200010 ENDDATA 3 0 1267900200011 ENDSUBENT 10 0 1267900299999 SUBENT 12679003 20220309 14981267900300001 BIB 3 3 1267900300002 REACTION (3-LI-7(N,EL)3-LI-7,,SIG) 1267900300003 STATUS (TABLE) page 4. 1267900300004 HISTORY (20220210C) BP 1267900300005 ENDBIB 3 0 1267900300006 NOCOMMON 0 0 1267900300007 DATA 3 1 1267900300008 EN DATA DATA-ERR 1267900300009 MEV B B 1267900300010 14. 1.05 0.08 1267900300011 ENDDATA 3 0 1267900300012 ENDSUBENT 11 0 1267900399999 ENDENTRY 3 0 1267999999999