ENTRY 14699 20210420 14831469900000001 SUBENT 14699001 20210420 14831469900100001 BIB 10 24 1469900100002 TITLE The Neutron Absorption Limit in Cadmium 1469900100003 AUTHOR (J.G.Hoffman,M.S.Livingston) 1469900100004 REFERENCE (J,PR,52,1228,1937) 1469900100005 #doi:10.1103/PhysRev.52.1228 1469900100006 REL-REF (R,,F.Rasetti+,J,PR,49,104(1),1936) Cd data from the 1469900100007 wheel experiment. 1469900100008 INSTITUTE (1USACOR) 1469900100009 INC-SOURCE (RN-BE) 1469900100010 SAMPLE A shield of 20 mil Cd equivalent to 0.582 g Cd/cm2 1469900100011 covered the boron shield. 1469900100012 DETECTOR (BF3) BF3 gas chamber for the detection of the 1469900100013 neutrons. 1469900100014 METHOD (TRN) The Rn-Be source of neutrons was placed inside 1469900100015 a lead sphere of 3.65 cm radius around which was 1469900100016 fastened a paraffin shell 7.1 cm thick. The distance 1469900100017 from the center of the Rn-Be source to the outer 1469900100018 surface of the paraffin shell was 10.75 cm. The outer 1469900100019 wall of the BF3 gas chamber was placed 6.4 cm from 1469900100020 the paraffin surface. This chamber had a shielding 1469900100021 jacket of B4C of thickness equivalent to 0.391 g 1469900100022 B/cm2 the end of which lapped over the end of the 1469900100023 chamber in order to define accurately the aperture, 1469900100024 2.6 cm diameter, over which the absorbers were placed. 1469900100025 HISTORY (20210420C) BP 1469900100026 ENDBIB 24 0 1469900100027 COMMON 1 3 1469900100028 EN-DUMMY 1469900100029 EV 1469900100030 0.0253 1469900100031 ENDCOMMON 3 0 1469900100032 ENDSUBENT 31 0 1469900199999 SUBENT 14699002 20210420 14831469900200001 BIB 3 12 1469900200002 REACTION 1(48-CD-0(N,0),,EN) 1469900200003 2(48-CD-0(N,TOT),,WID) 1469900200004 3(48-CD-0(N,EL),,WID) 1469900200005 ANALYSIS A sheet of Cd 0.5 mm thick reduces the neutron counts 1469900200006 to 8.4 percent of the total; 5.7 percent are 1469900200007 absorbable in heavy layers of boron. Assuming the 1/v 1469900200008 law for the absorption of neutrons in boron the 1469900200009 absorption limit in Cd is found to be 0.41 eV. With 1469900200010 the aid of data from the wheel experiment of Rasetti 1469900200011 and collaborators the resonance energy and the 1469900200012 half-width are calculated. 1469900200013 STATUS (TABLE) page 1231. 1469900200014 ENDBIB 12 0 1469900200015 NOCOMMON 0 0 1469900200016 DATA 3 1 1469900200017 DATA 1DATA 2DATA 3 1469900200018 EV EV EV 1469900200019 0.18 0.15 1.3E-03 1469900200020 ENDDATA 3 0 1469900200021 ENDSUBENT 20 0 1469900299999 ENDENTRY 2 0 1469999999999