ENTRY 21867 19840416 00002186700000001 SUBENT 21867001 19840416 00002186700100001 BIB 15 49 2186700100002 INSTITUTE (2JPNJPN) ELECTROTECHNICAL LABORATORY, RADIATION 2186700100003 METROLOGY SECTION. 2186700100004 REFERENCE (J,AEJ,23,(1),62,80) 2186700100005 AUTHOR (K.KUDO) 2186700100006 TITLE -ABSOLUTE CALIBRATION OF ETL STANDARD CF-252 2186700100007 NEUTRON SOURCES BY CIRCULATED MANGANESE 2186700100008 SULPHATE TECHNIQUE.-(IN JAPANESE)- 2186700100009 INC-SOURCE (CF252) 5.4 MILLI-CURIE AT THE CENTRE OF AN 2186700100010 ALUMINIUM SPHERICAL SHELL OF 9.1 CM DIAMETER 2186700100011 WHICH WAS PLACED IN ITS TURN AT THE CENTRE OF 2186700100012 THE MAGNESIUM BATH VESSEL. THE NEUTRONS ARE 2186700100013 THERMALISED BY THE BATH. THE SPECTRUM IS 2186700100014 EVALUATED BY THE GOLD-ACTIVATION METHOD. 2186700100015 INC-SPECT .THERMAL MAXWELLIAN SPECTRUM. 2186700100016 SAMPLE .THE BATH ITSELF. 2186700100017 METHOD (MANGB) MANGANESE BATH INSIDE A SPHERICAL SUS316 2186700100018 VESSEL, 1.5 MM THICK AND WITH AN INTERNAL DIAMETER 2186700100019 OF 98.4 CM. 2186700100020 .ACTIVATION. THE CONCENTRATION OF MN-S-O(4) INSIDE 2186700100021 THE BATH IS CHANGED. THE CROSS SECTION IS OBTAINED 2186700100022 FROM A STRAIGHT LINE EQUATION RELATING THE ACTIVATION 2186700100023 OF THE BATH TO THE CONCENTRATION. THE ACTIVATION 2186700100024 IS MEASURED BY PUMPING THE SOLUTION FROM THE 2186700100025 BATH AND COUNTING IT IN 2186700100026 DETECTOR (NAICR) 2 NA-I CRYSTAL DETECTORS, RESP. 2.5 CM DIAM * 2186700100027 2.5 CM LONG AND 5.1 CM DIAM * 5.1 CM LONG, BOTH 2186700100028 COUPLED TO TEMPERATURE COMPENSATED PM BASES. THE 2186700100029 EFFICIENCY OF THE BATH WAS DETERMINED AS FOLLOWS - 2186700100030 MN-055 WAS ACTIVATED IN A REACTOR. A PART OF SUCH A 2186700100031 SAMPLE WAS INTRODUCED INTO THE BATH AND COUNTED, 2186700100032 ANOTHER PART WAS COUNTED IN A 2186700100033 (D4PI ) 4*PI B-G COINCIDENCE MEASUREMENT. 2186700100034 (LONGC) A STANDARD LONG COUNTER OF THE HANSON AND 2186700100035 MCKIBBEN TYPE WAS USED TO EVALUATE THE NEUTRON 2186700100036 ESCAPE FROM THE BATH. AND A 2186700100037 (BF3 ) BF3 COUNTER WAS USED TO MEASURE THE THERMAL 2186700100038 NEUTRONS AT THE SURFACE OF THE BATH. 2186700100039 PART-DET (DG ) DECAY GAMMAS. ALL GAMMAS WITH AN ENERGY 2186700100040 GREATER THAN 20 KEV WERE INTEGRATED. 2186700100041 COMMENT .METHOD ALSO DESCRIBED IN AEJ,23,1(1980)62. 2186700100042 STATUS .DATA TAKEN FROM MAIN REFERENCE. 2186700100043 HISTORY (830804C) G.C. 2186700100044 (831004E) 2186700100045 (840106U) A.P.T. JAPAN CODE CHANGED TO JPN 2186700100046 (840106E) 2186700100047 CORRECTION .NEUTRON ABSORPTION IN SOURCE AND SOURCE MOUNTING. 2186700100048 .(N,A) AND (N,P) REACTIONS. 2186700100049 .NON 1/V ACTIVATION. 2186700100050 ERR-ANALYS (ERR-T) NO DETAILS GIVEN. 2186700100051 ENDBIB 49 0 2186700100052 COMMON 1 3 2186700100053 EN-DUMMY 2186700100054 EV 2186700100055 2.5300E-02 2186700100056 ENDCOMMON 3 0 2186700100057 ENDSUBENT 56 0 2186700199999 SUBENT 21867002 19840206 00002186700200001 BIB 3 5 2186700200002 REACTION ((1-H-1(N,G)1-H-2,,SIG,,MXW)/ 2186700200003 (25-MN-55(N,G)25-MN-56,,SIG,,MXW)) 2186700200004 STATUS .DATA TAKEN FROM MAIN REFERENCE. 2186700200005 HISTORY (830804C) G.C. 2186700200006 (831004E) 2186700200007 ENDBIB 5 0 2186700200008 NOCOMMON 0 0 2186700200009 DATA 2 1 2186700200010 DATA ERR-T 2186700200011 NO-DIM NO-DIM 2186700200012 2.5310E-02 7.0000E-05 2186700200013 ENDDATA 3 0 2186700200014 ENDSUBENT 13 0 2186700299999 ENDENTRY 2 0 2186799999999