ENTRY 20457 19840120 00002045700000001 SUBENT 20457001 19840120 00002045700100001 BIB 14 50 2045700100002 INSTITUTE (2UK HAR) 2045700100003 REFERENCE (J,JIN,31,1229,6905) 2045700100004 AUTHOR (M.J.CABELL, M.WILKINS) 2045700100005 TITLE -GAMMA-RAY SPECTROMETRIC MEASUREMENTS OF THE CAPTURE 2045700100006 CROSS SECTION OF GOLD-198 FOR REACTOR NEUTRONS.- 2045700100007 INC-SOURCE (REAC )THE PLUTO REACTOR. 2045700100008 INC-SPECT REACTOR NEUTRONS WITH VARYING EPITHERMAL CONTENT. 2045700100009 SAMPLE .APPROX. 0.25 CM LENGTHS OF A 0.018 IN. DIA- 2045700100010 METER GOLD-ALUMINIUM ALLOY. 2045700100011 .THE GOLD CONTENT WAS DETERMINED BY X-RAY FLUORESCENCE 2045700100012 SPECTROGRAPHY, COLORIMETRY AND NEUTRON ACTIVATION 2045700100013 ANALYSIS TO GET THE WEIGHTED MEAN 0.698 +- 0.011 PER 2045700100014 CENT. 2045700100015 METHOD (ACTIV) ACTIVATION, DEDUCTION OF CROSS SECTION FOR 2045700100016 MAXWELLIAN NEUTRONS FROM VARIATION OF EFFECTIVE CROSS 2045700100017 SECTION FOR REACTOR NEUTRONS WITH EPITHERMAL CONSTANT 2045700100018 OF SPECTRUM. 2045700100019 DETECTOR (NAICR) 3 IN. * 3 IN. NAI(TL) CRYSTAL COUPLED TO AN 2045700100020 EMI TYPE 9531 B PHOTOMULTIPLIER FEEDING A LABEN 100- 2045700100021 CHANNEL SPECTRASCOPE. 2045700100022 .1 CM LENGTHS OF 0.005 IN. DIAMETER COBALT WIRE, 2 CM 2045700100023 LENGTHS OF A 0.025 IN. DIAMETER 1 PC SILVER IN AL- 2045700100024 ALLOY WIRE AND 2.5 MM LENGTHS OF A 0.050 IN. DIAMETER 2045700100025 0.976 PC COBALT IN AL-ALLOY WIRE WERE USED AS NEUTRON 2045700100026 FLUX AND EPITHERMAL INDEX MONITORS. 2045700100027 ANALYSIS COMPUTER ANALYSIS OF GAMMA SPECTRA. 2045700100028 COMMENT .IN THE PRESENT EXPERIMENTS THE NEUTRON TEMPERATURE 2045700100029 WAS KNOWN TO VARY OVER THE RANGE OF SPECTRUM EMPLOYED 2045700100030 BY, AT MOST, 44 DEG C, BUT MORE PROBABLY BY 30 DEG C, 2045700100031 THUS THE NEUTRON TEMPERATURE AT THE CORE OF PLUTO IS 2045700100032 100 +- 10 DEG C. 2045700100033 .ASSUMING THE 2200 M/SEC CAPTURE CROSS SECTION OF CO59 2045700100034 TO BE 37.4 BARN IT WAS FOUND THAT, 2045700100035 THE CAPTURE CROSS SECTION OF AU198 2045700100036 = 25102 - 46535 * R * ROOT(T/T(0)), 2045700100037 WHERE R * ROOT(T/T(0)) IS WESTCOTT S EPITHERMAL INDEX 2045700100038 PARAMETER. THE CROSS SECTION FOR MAXWELLIAN NEUTRONS 2045700100039 (T = 70 DEG C) WAS GIVEN. 2045700100040 HISTORY (710108C) 2045700100041 (760112E) 2045700100042 CORRECTION .THE AMOUNT OF AU198 PRODUCED DURING THE IRRADIATIONS 2045700100043 DID NOT EXCEED ABOUT 0.5 PER CENT OF THE AU197 CONTENT2045700100044 OF THE TARGET AT ANY TIME. UNDER THESE CONDITIONS 2045700100045 AU198 MAKES A VARYING, BUT ALWAYS NEGLIGIBLE, 2045700100046 CONTRIBUTION TO THE THERMAL NEUTRON SELF-SHIELDING 2045700100047 FACTOR (REDUCING IT BY 0.0002 AT MOST). 2045700100048 .SMALL CORRECTION (LESS THAN 0.25 PER CENT) FOR NA24 2045700100049 (PRODUCED BY THE REACTION AL27(N,A)NA24) CONTRIBUTION 2045700100050 TO GAMMA-SPECTRUM MADE. 2045700100051 ERR-ANALYS SYSTEMATIC ERRORS PLUS 1 SIGMA. 2045700100052 ENDBIB 50 0 2045700100053 NOCOMMON 0 0 2045700100054 ENDSUBENT 53 0 2045700199999 SUBENT 20457002 19840120 00002045700200001 BIB 5 7 2045700200002 REACTION (79-AU-198(N,G)79-AU-199,,SIG) 2045700200003 MONITOR (27-CO-59(N,G)27-CO-60,,SIG) 2045700200004 = 37.4 +- 0.3 B FOR THERMAL NEUTRONS. 2045700200005 PART-DET (G ) GAMMAS. 2045700200006 STATUS (APRVD) APPROVED BY CABELL. 2045700200007 HISTORY (710108C) 2045700200008 (760112E) 2045700200009 ENDBIB 7 0 2045700200010 NOCOMMON 0 0 2045700200011 DATA 3 1 2045700200012 EN-DUMMY DATA DATA-ERR 2045700200013 MEV B B 2045700200014 2.5300E-08 2.5102E+04 3.7100E+02 2045700200015 ENDDATA 3 0 2045700200016 ENDSUBENT 15 0 2045700299999 ENDENTRY 2 0 2045799999999