ENTRY 20634 19840127 00002063400000001 SUBENT 20634001 19840127 00002063400100001 BIB 15 82 2063400100002 INSTITUTE (2GERMUN) 2063400100003 REFERENCE (J,JIN,36,1447,7407) 2063400100004 (T,GRYNTAKIS,,7603) THESIS DM-6909(1976),TECHNICAL 2063400100005 UNIVERSITY OF MUNICH. THE SAME RESULTS ARE 2063400100006 INCLUDED (IN GERMAN). 2063400100007 (J,RCA,22,128,75) CALCULATION OF G-FACTOR FOR 2063400100008 (N,G)- AND (N,F)-REACTIONS OF NON 1/V-NUCLIDES. 2063400100009 AUTHOR (E.M.GRYNTAKIS,J.I.KIM) 2063400100010 TITLE -THE THERMAL CROSS SECTION AND THE RESONANCE INTEGRAL 2063400100011 OF PA-231.ACTIVATION DETERMINATION WITHOUT USING 2063400100012 A CD-FILTER-. 2063400100013 INC-SOURCE (REAC ) PNEUMATIC POSITIONS,REFLECTOR AND ROTATING 2063400100014 DISK FACILITY OF FRM-REACTOR IN MUNICH. 2063400100015 SAMPLE .FROM A STOCK SOLUTION OF PA-231 IN 0.05 N HF (AFTER 2063400100016 PURIFICATION WITH ANION EXCHANGE) AN ALIQUOT 2063400100017 CONTAINING ABOUT 1 MG PA-231 IS DRIED ON A SMALL 2063400100018 PIECE OF PURE AL-FOIL. 2063400100019 .FOR THE STANDARDS AU-AL-ALLOY WIRE (AU, 0.132 PER 2063400100020 CENT) AND CO-AL-ALLOY WIRE (CO, 0.564 PER CENT) 2063400100021 HAVE BEEN USED. 2063400100022 METHOD (ACTIV) ACTIVATION. 2063400100023 .DEVELOPMENT OF A NEW METHOD WITHOUT USING A CADMIUM 2063400100024 FILTER (SEE ANALYSIS). 2063400100025 .CADMIUM FILTER MEASUREMENTS,WESTCOTT FORMALISM. 2063400100026 DETECTOR (GELI )GE(LI)-DETECTORS COUPLED TO A ND4420 ANALYSER. 2063400100027 (SCIN ) THE ALPHA ACTIVITY OF PA-231 AND U-232 WAS 2063400100028 MEASURED WITH A HOME-MADE LIQUID SCINTILLATION 2063400100029 COUNTER. 2063400100030 ANALYSIS .BECAUSE OF THE LOW ENERGY RESONANCES AT 0.396 EV AND 2063400100031 0.494 EV OF PA-231, THE CONTRIBUTION OF THESE RESO- 2063400100032 NANCES TO THE RESONANCE INTEGRAL (IT IS ABOUT 76 2063400100033 PER CENT) WILL BE REDUCED WHEN A CADMIUM FILTER IS 2063400100034 USED (CADMIUM-CUT-OFF-ENERGY = 0.55 EV). 2063400100035 .IN ORDER TO MEASURE THE TOTAL RESONANCE INTEGRAL 2063400100036 (FROM AN ENERGY GREATER THAN ABOUT 0.2 EV) A 2063400100037 NEW METHOD IS DEVELOPED WHICH IS BASED ON IRRADIA- 2063400100038 TIONS IN TWO DIFFERENT NEUTRON SPECTRA WITH KNOWN 2063400100039 NEUTRON TEMPERATURE AND EPITHERMAL INDEX. 2063400100040 .THE NEUTRON TEMPERATURE WAS MEASURED USING THE 2063400100041 NEUTRON TEMPERATURE DETECTOR LU-176 (FOR THESE 2063400100042 MEASUREMENTS SEE THESIS DM-6909). 2063400100043 .THE EPITHERMAL COMPONENT WAS MEASURED USING 2063400100044 AU-197 AND CO-59 AS MONITORS. 2063400100045 .THE S0-FACTOR (WESTCOTT FORMALISM) WAS CALCULATED 2063400100046 FROM THE RELATION S0=(G2*(R1/R2)-G1)/(F1-(R1-R2)*F2) 2063400100047 WHERE R,G,F ARE THE INDUCED ACTIV. (EITHER OF PA-232 2063400100048 OR OF U-232),THE G-FACTOR AND THE EPITHERMAL INDEX 2063400100049 OF THE IRRADIATION POSITIONS 1 AND 2,RESPECTIVELY. 2063400100050 .THE G-FACTORS ARE REPORTED IN REF. RCA,22(1975),128. 2063400100051 .FOR COMPARISON THE CADMIUM METHOD HAS BEEN ALSO 2063400100052 USED. 2063400100053 MONITOR (79-AU-197(N,G)79-AU-198,,RI) 2063400100054 THERMAL CROSS SECTION = 98.8+-0.3B, 2063400100055 RES.INTEGRAL INCLUDING THE 1/V-PART = 1551 +-12B. 2063400100056 (27-CO-59(N,G)27-CO-60,,RI) 2063400100057 THERMAL CROSS SECTION = 37.2 +0.6B, 2063400100058 RES.INTEGRAL INCLUDING THE 1/V-PART = 71.1 +- 4.0B. 2063400100059 COMMENT .NEW METHOD FOR MEASUREMENT OF THERMAL CROSS SECTION 2063400100060 AND RES. INTEGRAL OF NUCLIDES WHOSE DIFFERENTIAL 2063400100061 CROSS SECTIONS DO NOT OBEY THE 1/V-LAW BELOW 2063400100062 THE CADMIUM-CUT-OFF-ENERGY. 2063400100063 .A COMPILATION OF THE THERMAL CROSS SECTIONS AND 2063400100064 RESONANCE INTEGRALS OF PA-231 IS ALSO GIVEN. 2063400100065 STATUS .TAKEN FROM J.INORG.NUCL.CHEM., 36(1974)1447. 2063400100066 HISTORY (760728C) 2063400100067 (770331E) 2063400100068 CORRECTION .THE SPECTRUM OF THE IRRADIATION POSITIONS HAS A 2063400100069 KNOWN 1/E FORM. 2063400100070 .BECAUSE OF THE THIN SAMPLES NO CORRECTION FOR 2063400100071 SELF SHIELDING AND SELF ABSORPTION IS NEEDED. 2063400100072 ERR-ANALYS .THE UNCERTAINTY IN THE G-FACTORS OF PA-231 (ABOUT 2063400100073 +-2 PER CENT) AND THE UNCERTAINTY OF EPITHERMAL 2063400100074 INDICES CONTRIBUTE TO THE THERMAL CROSS SECTION 2063400100075 THE MAXIMUM DEVIATIONS OF 4.1 PER CENT AND 6.0 2063400100076 PER CENT,RESPECTIVELY. 2063400100077 .THE ALPHA MEASUREMENTS WITH THE SCINTILLATION COUNTER 2063400100078 HAVE AN ACCURACY OF +- 2 PER CENT. 2063400100079 .THE HALF LIFE OF PA-232 AND THE INTENSITIES OF THE 2063400100080 MEASURED GAMMA RAYS ARE KNOWN WITH GOOD ACCURACY. 2063400100081 .STANDARD DEVIATION. 2063400100082 .UNCERTAINTIES IN THE THERMAL CROSS SECTIONS AND 2063400100083 RESONANCE INTEGRALS OF THE STANDARDS. 2063400100084 ENDBIB 82 0 2063400100085 NOCOMMON 0 0 2063400100086 ENDSUBENT 85 0 2063400199999 SUBENT 20634002 19840127 00002063400200001 BIB 3 6 2063400200002 REACTION (91-PA-231(N,G)91-PA-232,,SIG,,MXW) 2063400200003 ACTIVATION THERMAL CROSS SECTION. 2063400200004 FLAG (1.) METHOD WITHOUT USING CADMIUM-FILTER. 2063400200005 (2.) CADMIUM-FILTER METHOD. 2063400200006 HISTORY (760728C) 2063400200007 (770331E) 2063400200008 ENDBIB 6 0 2063400200009 COMMON 1 3 2063400200010 EN-DUMMY 2063400200011 EV 2063400200012 2.5300E-02 2063400200013 ENDCOMMON 3 0 2063400200014 DATA 3 2 2063400200015 DATA DATA-ERR FLAG 2063400200016 B B NO-DIM 2063400200017 2.0100E+02 2.2000E+01 1.0000E+00 2063400200018 2.1800E+02 1.4000E+01 2.0000E+00 2063400200019 ENDDATA 4 0 2063400200020 ENDSUBENT 19 0 2063400299999 SUBENT 20634003 19840127 00002063400300001 BIB 2 5 2063400300002 REACTION (91-PA-231(N,G)91-PA-232,,RI,,RNV) 2063400300003 ACTIVATION RESONANCE INTEGRAL 2063400300004 EXCLUDING THE 1/V-CONTRIBUTION. 2063400300005 HISTORY (760728C) 2063400300006 (770331E) 2063400300007 ENDBIB 5 0 2063400300008 NOCOMMON 0 0 2063400300009 DATA 3 2 2063400300010 EN-MIN DATA DATA-ERR 2063400300011 EV B B 2063400300012 2.0000E-01 1.4320E+03 1.8700E+02 2063400300013 5.1200E-01 7.4300E+02 6.7000E+01 2063400300014 ENDDATA 4 0 2063400300015 ENDSUBENT 14 0 2063400399999 ENDENTRY 3 0 2063499999999