ENTRY C2883 20230112 C227C2883000 1 SUBENT C2883001 20230112 C227C2883001 1 BIB 11 38 C2883001 2 TITLE Angular Distribution of Neutrons Produced by 40- and C2883001 3 80-Mev Alpha Particles on a Thick Tantalum Target C2883001 4 AUTHOR (W.W.Wadman) C2883001 5 REL-REF (O,14818001,W.W.Wadman,R,UCRL-11375,1964) Neutron C2883001 6 measurements. C2883001 7 REFERENCE (J,HP,11,659,1965) C2883001 8 (R,UCRL-11375,1964) Similar to J,HP,11,659,1965 C2883001 9 INSTITUTE (1USABRK) C2883001 10 FACILITY (CYCLO,1USABRK) The 88-Inch Cyclotron at Berkeley. C2883001 11 DETECTOR (NAICR) 3-in. diam 3-in. long NaI(Tl) crystal and a C2883001 12 400-channel pulse-height analyzer. A collection of C2883001 13 threshold detectors was used: 58Ni(n,p)58Co, C2883001 14 59Co(n,alpha)56Mn, 65Cu(n,p)65Ni, 27Al(n,alpha)24Na, C2883001 15 203Th(n,2n)202Tl, 127I(n,2n)126I, and 58Ni(n,2n)57Ni. C2883001 16 SAMPLE The target was made of tantalum, and measured 2.5 in. C2883001 17 in diameter and 0.25 in. thick. This dimension was C2883001 18 adequate for stopping the alpha particles and for C2883001 19 covering the end of the copper Faraday cup in which C2883001 20 it was mounted. C2883001 21 METHOD (TTM) The experiment involved a target of a selected C2883001 22 material, a means of measuring the beam particle C2883001 23 current, the selected threshold detectors, a device C2883001 24 to mount the detectors at predetermined positions, C2883001 25 and a means to suppress secondary emission electrons C2883001 26 from escaping the current-measuring device. Each C2883001 27 threshold detector was counted at 3.0 cm from the C2883001 28 actual face of the NaI crystal. The resultant C2883001 29 gamma-ray spectra were used during the reduction of C2883001 30 the data. C2883001 31 CORRECTION The total counts in the photopeak were corrected for C2883001 32 decay and saturation. A correction was made for the C2883001 33 abundance of the gamma ray for the decay scheme for C2883001 34 each type of disintegration. The data were corrected C2883001 35 for counting geometry and total absolute efficiency C2883001 36 for the size of the NaI crystal, gamma-ray energies C2883001 37 distance of the sample from the crystal, and sample C2883001 38 size and thickness. C2883001 39 HISTORY (20230112C) BP C2883001 40 ENDBIB 38 0 C2883001 41 NOCOMMON 0 0 C2883001 42 ENDSUBENT 41 0 C288300199999 SUBENT C2883002 20230112 C227C2883002 1 BIB 4 11 C2883002 2 REACTION (73-TA-181(A,X)0-NN-1,,PY,,TT/CH) C2883002 3 ERR-ANALYS (ERR-3) Uncertainty in neutron flux C2883002 4 (ERR-1) Beam current error. C2883002 5 (ERR-2) Angular resolution. C2883002 6 (ERR-T) Total uncertainty C2883002 7 CORRECTION Conversion from photopeak counts to neutron flux is C2883002 8 considered to be +-15%. All variations affect the C2883002 9 entire set of threshold detector data and do not C2883002 10 change the shape of the curve. The beam current was C2883002 11 known to +-3%, and detector angular location was +-1%. C2883002 12 STATUS (TABLE) p.664, J,HP,11,659,1965 C2883002 13 ENDBIB 11 0 C2883002 14 COMMON 4 3 C2883002 15 ERR-3 ERR-1 ERR-2 ERR-T C2883002 16 PER-CENT PER-CENT PER-CENT PER-CENT C2883002 17 15.0 3.0 1.0 25. C2883002 18 ENDCOMMON 3 0 C2883002 19 DATA 3 2 C2883002 20 EN EN-ERR DATA C2883002 21 MEV MEV PRD/MUCOUL C2883002 22 40. 0.4 1.96E+10 C2883002 23 80. 1.0 3.0E+11 C2883002 24 ENDDATA 4 0 C2883002 25 ENDSUBENT 24 0 C288300299999 ENDENTRY 2 0 C288399999999