ENTRY 20663 19840127 00002066300000001
SUBENT 20663001 19840127 00002066300100001
BIB 16 97 2066300100002
INSTITUTE (2GERKFK) INSTITUT FUER NEUTRONENPHYSIK UND REAKTOR- 2066300100003
TECHNIK. 2066300100004
REFERENCE (R,KFK-2191,,750806)ALSO AS THESIS ACCEPTED AT THE 2066300100005
FACULTY FOR ENGINEERING OF THE UNIVERSITY OF 2066300100006
KARLSRUHE. 2066300100007
(J,NSE,61,(4),471,7612) 2066300100008
AUTHOR (C.S.YEN) 2066300100009
TITLE -MEASUREMENTS OF THE RATIO OF THE CROSS SECTIONS OF 2066300100010
235-U FOR CAPTURE AND FISSION IN THE NEUTRON ENERGY 2066300100011
RANGE 200 EV TO 20 KEV- 2066300100012
FACILITY (CCW ) COCKCROFT-WALTON-TYPE ACCELERATOR (150 KV,50 2066300100013
MICROAMP AT A PULSELENGTH OF 0.5 MICROSEC AND 2066300100014
625 PPS REPETITIONRATE) USED FOR MAIN EXPERIMENT. 2066300100015
.THE EXPERIMENTAL REACTOR STARK OF THE INSTITUTE WAS 2066300100016
USED FOR THE CALIBRATION MEASUREMENTS. 2066300100017
INC-SOURCE (D-T ) WITH THE REACTION 3H(D,N)4HE 14 MEV NEUTRONS 2066300100018
WERE CREATED IN A TRITIUM-TITANIUM TARGET. 2066300100019
(THCOL) THE THERMAL COLUMN OF THE EXPERIMENTAL 2066300100020
REACTOR STARK OF THE INSTITUT FUER NEUTRONENPHYSIK 2066300100021
UND REAKTORTECHIK (5 W CONSTANT POWER) SUPPLIED THE 2066300100022
FLUX FOR THE CALIBRATION OF THE FISSION DETECTOR. 2066300100023
SAMPLE .FOR THE SUM-MEASUREMENT U-235 FOILS (3.57,8.92, 2066300100024
17.84X10E+20 ATOMS/CM2,93.5PC U-235) WERE PLACED AS 2066300100025
ZYLINDERS AROUND THE PROPORTIONAL COUNTER. 2066300100026
.SAMPLE AND DETECTOR FOR THE FISSION REACTION WERE 2066300100027
ONE AND THE SAME. 2066300100028
METHOD (SLODT) A SLOWING DOWN TIME SPECTROMETER IN THE FORM 2066300100029
OF A PB-PILE(2X2X2M3,99.99PC PURITY) IN CONNECTION 2066300100030
WITH THE COCKCROFT-WALTON ACCELERATOR WAS USED TO 2066300100031
CREATE A SLOW FLUX (200 EV TO 20 KEV).ENERGY- 2066300100032
DETERMINATION WAS ACHIEVED FROM THE MEASUREMENT OF 2066300100033
THE SLOWING-DOWN-TIME. 2066300100034
.DETAILED DESCRIPTION SEE REFERENCE. 2066300100035
DETECTOR (PROPC) A GAMMA-PROPORTIONAL COUNTER WAS USED TO 2066300100036
MEASURE THE SUM OF FISSION AND CAPTURE EVENTS. 2066300100037
.IT WAS EMBEDDED IN THE SAMPLES. 2066300100038
.THE CYLINDRICAL COUNTER CONSISTED OF ALMG3 OF A 2066300100039
THICKNESS OF 5.5MM WITH A TUNGSTEN ANODE (DIAMETER 2066300100040
50 MICRON).IT WAS FILLED WITH 1.5 BAR ARGON AND 2066300100041
0.02 BAR CO2.THE OUTER DIAMETER WAS 27MM, LENGTH 2066300100042
370MM, HIGHEST OPERATING VOLTAGE 2500V. 2066300100043
.THE EFFICIENCY WAS DETERMINED BY CALIBRATED GAMMA- 2066300100044
SOURCES FROM THE RADIOCHEMICAL CENTRE,AMERSHAM, 2066300100045
ENGLAND,AND WITH THE HELP OF A 24NA-SOURCE, CREATED 2066300100046
BY IRRADIATION OF 23NA FROM THE THERMAL COLUMN OF 2066300100047
THE EXPERIMENTAL REACTOR FR2. 2066300100048
(FISCH) 2 FISSION CHAMBERS(U-235,ARGON) WERE USED, TO 2066300100049
DETERMINE THE FISSION EVENT RATE. 2066300100050
.CALIBRATION IN THE THERMAL FLUX OF STARK. 2066300100051
.THERMAL FLUX FOR CALIBRATION MONITORED BY A U-235, 2066300100052
ARGON-FILLED FISSION CHAMBER. 2066300100053
.U-238 FISSION CHAMBER TO MONITOR THE TIME-DEPENDENT 2066300100054
BEHAVIOUR OF NEUTRON PRODUCTION. 2066300100055
.BF3-COUNTOR TO MONITOR THE FLUX IN THE VICINITY OF 2066300100056
THE SAMPLE. 2066300100057
ANALYSIS .AS NORMALIZING STANDARD FOR THE MEASUREMENT OF THE 2066300100058
FISSION RATE (EFFICIENCY OF FISSION CHAMBER) A 2066300100059
MEASUREMENT IN THERMAL REACTORFLUX WAS UNDERTAKEN 2066300100060
AND THE NECESSARY THERMAL FISSION AND CAPTURE CROSS 2066300100061
SECTIONS TAKEN FROM TABULATIONS (REF. NOT GIVEN). 2066300100062
.ENERGY SPECTRUM DEDUCED FROM SLOWING DOWN TIME 2066300100063
SPECTRUM.TIME AND SPACE DEPENDENT NEUTRON FLUX 2066300100064
DETERMINED VIA INSTATIONARY ENERGY-DEPENDENT 2066300100065
TRANSPORT THEORY, DIFFUSION THEORY AND FERMI-AGE 2066300100066
THEORY. 2066300100067
.THE NECESSARY CONSTANTS HAVE BEEN DETERMINED BY 2066300100068
EITHER MONTE-CARLO CALCULATIONS OR EXPERIMENTALLY. 2066300100069
.FOR DETAILS SEE REFERENCE. 2066300100070
PART-DET (G ) GAMMAS DETECTED BY PROPORTIONAL COUNTERS TO 2066300100071
GIVE THE NUMBER OF FISSION AND CAPTURE EVENTS. 2066300100072
(N ) FISSION RATE WAS DETERMINED BY USE OF A 2066300100073
NEUTRON DETECTING FISSION CHAMBER. 2066300100074
COMMENT .SYSTEMATIC ERROR POSSIBLE,SINCE ANALYSIS WAS CARRIED 2066300100075
OUT UNDER THE ASSUMPTION, THAT THE MEAN PROMPT 2066300100076
GAMMA-ENERGY PER FISSION IS INDEPENDENT OF THE 2066300100077
NEUTRON-ENERGY. 2066300100078
STATUS .ALPHA VALUES TAKEN FROM REFERENCE. 2066300100079
HISTORY (761012C) 2066300100080
(770504E) 2066300100081
(810112A) ERR-COLUMNS CHANGED. 2066300100082
(810120E) 2066300100083
CORRECTION .FOR CALIBRATION MEASUREMENTS 2066300100084
DELAYED FISSION GAMMAS, 2066300100085
NATURAL ACTIVITY OF THE URANIUM, 2066300100086
ACTIVITY DUE TO THE CREATION OF 2066300100087
FISSION PRODUCTS FROM PREVIOUS IRRADIATIONS. 2066300100088
.FOR THE MAIN EXPERIMENT 2066300100089
NATURAL RADIOACTIVITY, 2066300100090
ACTIVATION DURING DURATION OF EXPERIMENT, 2066300100091
NEUTRONS FROM PREVIOUS BEAM BURSTS,(LESS THAN 1 PC), 2066300100092
CAPTURE-GAMMA-RAYS IN PILE AND COUNTER, 2066300100093
SELF-ABSORPTION, 2066300100094
DEAD-TIME OF ANALYZER (16 MICROSEC,4PC CORRECTION), 2066300100095
NEUTRON SCATTERING IN THE GAMMA-COUNTER. 2066300100096
ERR-ANALYS (ERR-S) STATISTICAL ERRORS- LESS THAN 1 PC. 2066300100097
(ERR-T) TOTAL ERRORS BETWEEN 13 AND 20 PC. 2066300100098
.ERROR IN CALIBRATION- 3.2 PC(80PC OF TOTAL). 2066300100099
ENDBIB 97 0 2066300100100
NOCOMMON 0 0 2066300100101
ENDSUBENT 100 0 2066300199999
SUBENT 20663002 19840127 00002066300200001
BIB 3 7 2066300200002
REACTION (92-U-235(N,ABS),,ALF) 2066300200003
COMMENT .THE ENERGY RESOLUTION IS 25 PC AT 200 EV AND 50 PC 2066300200004
AT 20 KEV. 2066300200005
HISTORY (761021C) 2066300200006
(770504E) 2066300200007
(810112A) 2066300200008
(810120E) 2066300200009
ENDBIB 7 0 2066300200010
NOCOMMON 0 0 2066300200011
DATA 4 24 2066300200012
EN DATA ERR-T ERR-S 2066300200013
KEV NO-DIM NO-DIM NO-DIM 2066300200014
2.0000E-01 7.6000E-01 1.0000E-01 2066300200015
2.5000E-01 7.0000E-01 3.0000E-02 2066300200016
3.0000E-01 7.2000E-01 3.0000E-02 2066300200017
3.5000E-01 7.1000E-01 3.0000E-02 2066300200018
4.1000E-01 6.1000E-01 3.0000E-02 2066300200019
4.7000E-01 5.7000E-01 5.0000E-02 2066300200020
5.6000E-01 3.6000E-01 4.0000E-02 2066300200021
6.1000E-01 3.8000E-01 5.0000E-02 2066300200022
7.0000E-01 4.8000E-01 5.0000E-02 2066300200023
7.9000E-01 5.3000E-01 5.0000E-02 2066300200024
9.1000E-01 5.8000E-01 5.0000E-02 2066300200025
1.0500E+00 5.8000E-01 3.0000E-02 2066300200026
1.2800E+00 5.1000E-01 3.0000E-02 2066300200027
1.5400E+00 4.5000E-01 6.0000E-02 2066300200028
1.8500E+00 4.7000E-01 5.0000E-02 2066300200029
2.1100E+00 4.5000E-01 3.0000E-02 2066300200030
2.6800E+00 4.2000E-01 3.0000E-02 2066300200031
3.3700E+00 3.3000E-01 3.0000E-02 2066300200032
4.2300E+00 3.8000E-01 4.0000E-02 2066300200033
5.1700E+00 3.5000E-01 2.0000E-02 2066300200034
6.3300E+00 3.6000E-01 2.0000E-02 2066300200035
7.8200E+00 3.6000E-01 2.0000E-02 2066300200036
9.3500E+00 3.7000E-01 2.0000E-02 2066300200037
1.2760E+01 3.3000E-01 7.0000E-02 2066300200038
ENDDATA 26 0 2066300200039
ENDSUBENT 38 0 2066300299999
ENDENTRY 2 0 2066399999999