ENTRY 22147 19901227 00002214700000001 SUBENT 22147001 19901227 00002214700100001 BIB 14 68 2214700100002 REFERENCE (C,89WASH,2,705,8904) 2214700100003 TITLE -A STUDY OF MONOENERGETIC, FAST NEUTRON-INDUCED TERNARY2214700100004 FISSION IN 238-U. 2214700100005 AUTHOR (K.RANDLE,H.AFARIDEH) 2214700100006 INSTITUTE (2UK BIR) 2214700100007 FACILITY (DYNAM,2UK BIR) 2214700100008 INC-SOURCE (D-D ) THE NEUTRON SOURCE CONSISTED OF A 25 MM DIA- 2214700100009 METER DEUTERATED LAYER OF TI ON A 31.7 MM DIAMETER, 2214700100010 0.5 MM THICK AG BACKING. THE DISC WAS WATER COOLED TO 2214700100011 ALLOW DEUTERON BEAM CURRENTS OF ABOUT 200 MUA. 2214700100012 NEUTRON ENERGIES OF 3.6 AND 4.1 MEV WERE OBTAINED 2214700100013 BY BOMBARDING WITH 900 KEV AND 1.4 MEV DEUTERONS. 2214700100014 THE SOURCE WAS CONTAINED IN THE 40 CM DIAMETER VACUUM 2214700100015 CHAMBER SPECIALLY CONSTRUCTED FOR THE EXPERIMENT AND 2214700100016 MAINTAINED AT 1.0E-5 TORR. 2214700100017 METHOD 1(RELFY) SEVERAL DAYS OF IRRADIATION WERE REQUIRED TO 2214700100018 PRODUCE SUFFICIENT TERNARY FISSION EVENTS. 2214700100019 (EDE ) THE MASS DETERMINATION OF THE LCP WAS PERFORMED2214700100020 BY AN ELECTONICS UNIT CALLED THE PARTICLE IDENTIFICA- 2214700100021 TION UNIT (PIU) WHICH ANALYSED THE RESPONSES OF THE 2214700100022 'DELTA E' AND 'E' DETECTORS IN THE TELESCOPE. 2214700100023 2(FISCT) 2214700100024 DETECTOR 1(TELES,SOLST,SOLST) THE TRITONS AND ALPHA PARTICLES 2214700100025 WERE DETECTED WITH A PARTICLE DETECTOR TELESCOPE 2214700100026 CONSISTING OF TWO SURFACE BARRIER DETECTORS, SHIELDED 2214700100027 FROM HEAVY FISSION FRAGMENTS BY A 12 MICRON ALUMINIUM 2214700100028 FOIL, AND VARYING IN DISTANCE BETWEEN 25 TO 50 MM 2214700100029 FROM THE FISSION FOIL WITHIN THE VACUUM CHAMBER AT AN 2214700100030 ANGLE OF 30 DEG TO THE BEAM DIRECTION. THE 'DELTA E' 2214700100031 DETECTOR WAS FULLY DEPLETED WITH A THICKNESS OF ABOUT 2214700100032 50 MICRON AND ACTIVE AREA 75 MM2; THE 'E' DETECTOR HAD2214700100033 A THICKNESS OF 800 MICRON AND ACTIVE AREA OF 400 MM2, 2214700100034 INITIAL ENERGY RESOLUTION BEING 36 KEV FOR 6.05 MEV 2214700100035 ALPHAS. A WEAK ANNULAR 241-AM SOURCE WAS PERMANENTLY 2214700100036 MOUNTED BETWEEN THE 'DELTA E' AND 'E' DETECTORS TO 2214700100037 MONITOR CONTINUOUSLY THEIR RESOLUTION THROUGHOUT THE 2214700100038 EXPERIMENT. 2214700100039 2(SOLST) THE TOTAL NUMBER OF FISSION EVENTS WERE MONI- 2214700100040 TORED WITH A SEPARATE SURFACE BARRIER DETECTOR OF 2214700100041 THICKNESS 100 MICRON LOCATED 120 MM FROM THE 238-U 2214700100042 FISSION FOIL WITHIN THE VACUUM CHAMBER AT AN ANGLE OF 2214700100043 30 DEG TO THE BEAM DIRECTON. 2214700100044 PART-DET 1(T ) 2214700100045 (A ) 2214700100046 2(FF ) 2214700100047 SAMPLE .THE FISSION FOIL CONSISTED OF AN ELECTROSPRAYED 2214700100048 500 MICRO-G/CM2 LAYER OF 99.99% 238-U, 20 MM IN DIA- 2214700100049 METER, ON A 7 MICRON THICK AU-COATED POLYMIDE FOIL, 2214700100050 MOUNTED ON AN ANNULAR AL RING, INSIDE DIAMETER 30 MM, 2214700100051 AND POSITIONED IN THE VACUUM CHAMBER APPROXIMATELY 2214700100052 15 MM FROM THE NEUTRON SOURCE. THE 238-U DEPOSIT 2214700100053 THICKNESS WAS SUFFICIENT TO PRODUCE REASONABLE COUNT- 2214700100054 ING STATISTICS BUT DID NOT SERIOUSLY DEGRADE THE 2214700100055 ENERGY OF THE LCP. 2214700100056 CORRECTION .TO ALLOW FOR THE DIFFERENCE IN GEOMETRICAL COUNTING 2214700100057 EFFICIENCY OF THE TWO SETS OF DETECTORS, WHICH WERE 2214700100058 LOCATED AT DIFFERENT DISTANCES FROM THE 238-U FOIL, 2214700100059 MICA TRACK DETECTORS WERE USED TO RECORD THE HEAVY 2214700100060 FISSION FRAGMENTS AT THE TWO DETECTOR POSITIONS WITHIN2214700100061 THE VACUUM CHAMBER. THE TELESCOPE RECORDED A CONSIDER-2214700100062 ABLE BACKGROUND COUNT WHICH HAD TO BE REMOVED FROM THE2214700100063 TRITON-ALPHA SPECTRUM. INTERFERENCE FROM STRUCTURAL 2214700100064 MATERIALS AND CHANCE COINCIDENCE COUNTS WERE ALSO 2214700100065 ALLOWED FOR. 2214700100066 ERR-ANALYS NO DETAILS GIVEN. 2214700100067 STATUS .DATA TAKEN FROM MAIN REF. 2214700100068 HISTORY (900820C) S.W. 2214700100069 (900917E) 2214700100070 ENDBIB 68 0 2214700100071 NOCOMMON 0 0 2214700100072 ENDSUBENT 71 0 2214700199999 SUBENT 22147002 19900917 00002214700200001 BIB 3 5 2214700200002 REACTION ((92-U-238(N,F)1-H-3,TER,FY)/ 2214700200003 (92-U-238(N,F)2-HE-4,TER,FY)) 2214700200004 STATUS .DATA TAKEN FROM MAIN REF. 2214700200005 HISTORY (900820C) S.W. 2214700200006 (900917E) 2214700200007 ENDBIB 5 0 2214700200008 NOCOMMON 0 0 2214700200009 DATA 2 2 2214700200010 EN DATA 2214700200011 MEV NO-DIM 2214700200012 3.6000E+00 1.5700E-01 2214700200013 4.1000E+00 2.0500E-01 2214700200014 ENDDATA 4 0 2214700200015 ENDSUBENT 14 0 2214700299999 SUBENT 22147003 19900917 00002214700300001 BIB 4 7 2214700300002 REACTION (92-U-238(N,F)1-H-3,IND/TER,FY) 2214700300003 COMMENT .THE VALUE QUOTED IN THE REFERENCE IS THE RATIO OF THE 2214700300004 TRITON COUNTS TO THE TOTAL FISSION EVENTS - THIS HAS 2214700300005 BEEN MULTIPLIED BY 100 TO GIVE AN INDEPENDENT YIELD. 2214700300006 STATUS .DATA TAKEN FROM MAIN REF. 2214700300007 HISTORY (900820C) S.W. 2214700300008 (900917E) 2214700300009 ENDBIB 7 0 2214700300010 NOCOMMON 0 0 2214700300011 DATA 3 2 2214700300012 EN DATA DATA-ERR 2214700300013 MEV PC/FIS PC/FIS 2214700300014 3.6000E+00 1.8000E-02 4.0000E-03 2214700300015 4.1000E+00 2.4000E-02 6.0000E-03 2214700300016 ENDDATA 4 0 2214700300017 ENDSUBENT 16 0 2214700399999 SUBENT 22147004 19900917 00002214700400001 BIB 4 7 2214700400002 REACTION (92-U-238(N,F)2-HE-4,IND/TER,FY) 2214700400003 COMMENT .THE VALUE QUOTED IN THE REFERENCE IS THE RATIO OF THE 2214700400004 ALPHA COUNTS TO THE TOTAL FISSION EVENTS - THIS HAS 2214700400005 BEEN MULTIPLIED BY 100 TO GIVE AN INDEPENDENT YIELD. 2214700400006 STATUS .DATA TAKEN FROM MAIN REF. 2214700400007 HISTORY (900820C) S.W. 2214700400008 (900917E) 2214700400009 ENDBIB 7 0 2214700400010 NOCOMMON 0 0 2214700400011 DATA 3 2 2214700400012 EN DATA DATA-ERR 2214700400013 MEV PC/FIS PC/FIS 2214700400014 3.6000E+00 1.1300E-01 1.1000E-02 2214700400015 4.1000E+00 1.1500E-01 1.3000E-02 2214700400016 ENDDATA 4 0 2214700400017 ENDSUBENT 16 0 2214700499999 ENDENTRY 4 0 2214799999999