ENTRY 14701 20210421 14841470100000001 SUBENT 14701001 20210421 14841470100100001 BIB 9 21 1470100100002 TITLE On the Interaction of Fast Neutrons with Lead 1470100100003 AUTHOR (G.E.Gibson,G.T.Seaborg,D.C.Grahame) 1470100100004 REFERENCE (J,PR,51,370(1),1937) 1470100100005 #doi:10.1103/PhysRev.51.370 1470100100006 INSTITUTE (1USAUCX) 1470100100007 INC-SOURCE (RA-BE) 1470100100008 DETECTOR (GEMUC) 1470100100009 METHOD The counter wall was covered with 1.0 g/cm2 of lead. 1470100100010 When the Ra-Be was introduced into the large lead 1470100100011 block counts increased. With the 200 mc Ra-Be source 1470100100012 in the lead block additional lead (in plates 15x30 1470100100013 cm2) was placed behind the counter and produced a 1470100100014 further increase in the count. The increases in 1470100100015 counts vs. Pb thickness establish the existence of a 1470100100016 gamma-ray produced by the action of fast neutrons on 1470100100017 lead and the magnitude of its self-absorption 1470100100018 indicates an energy somewhat less than 1 MeV. 1470100100019 COMMENT Compiler's comment: It could be levels in 204,206, 1470100100020 207Pb below 1 MeV. Ra-Be neutron spectrum is below 13 1470100100021 MeV. 1470100100022 HISTORY (20210421C) BP 1470100100023 ENDBIB 21 0 1470100100024 COMMON 1 3 1470100100025 EN-MAX 1470100100026 MEV 1470100100027 13.0 1470100100028 ENDCOMMON 3 0 1470100100029 ENDSUBENT 28 0 1470100199999 SUBENT 14701002 20210421 14841470100200001 BIB 3 4 1470100200002 REACTION (82-PB-0(N,X)0-G-0,PAR,SIG,,SPA) 1470100200003 ANALYSIS Assuming an efficiency of 1 in 100 for counting a 1470100200004 gamma-ray of energy somewhat less than 1 MeV. 1470100200005 STATUS (TABLE) page 370. 1470100200006 ENDBIB 4 0 1470100200007 COMMON 1 3 1470100200008 E-MAX 1470100200009 MEV 1470100200010 1.0 1470100200011 ENDCOMMON 3 0 1470100200012 DATA 1 1 1470100200013 DATA 1470100200014 B 1470100200015 1.0 1470100200016 ENDDATA 3 0 1470100200017 ENDSUBENT 16 0 1470100299999 ENDENTRY 2 0 1470199999999