ENTRY 22114 20090401 22112211400000001 SUBENT 22114001 20090401 22112211400100001 BIB 14 64 2211400100002 REFERENCE (J,NIM/A,276,557,1989) 2211400100003 TITLE -Comparison of different methods for the determination 2211400100004 of fission fragment velocity, mass, and energy distri-2211400100005 butions for Th-232(N,F). 2211400100006 AUTHOR (K.Th.Brinkmann,J.Kiesewetter,F.M.Baumann, 2211400100007 H.Freiesleben,H.J.Lytke-Stetzkamp,H.J.Paul, 2211400100008 H.G.Schwanke,H.Sohlbach) 2211400100009 INSTITUTE (2GERBOC) 2211400100010 FACILITY (DYNAM,2GERBOC) 4 MV dynamitron tandem accelerator, 2211400100011 delivering an average proton current of 75 micro-amps.2211400100012 INC-SOURCE (P-LI7) A 100 micro-g/cm2 metallic lithium target with 2211400100013 natural abundance, evaporated onto an aluminium hut of2211400100014 16 mm diameter. The hut was water-cooled and served as2211400100015 a beam dump. The average neutron flux was 1.7e+07 2211400100016 N/cm2 sec through the fissile deposit. 2211400100017 .Two sets of measurements were performed. In the first 2211400100018 the proton beam was defocussed to a diameter of 12 mm,2211400100019 giving an energy resolution of about +/-20 KeV. In the2211400100020 second the well-focussed proton beam was scanned over 2211400100021 an area of 8 X 8 mm by deflection magnets, thus giving2211400100022 a better energy resolution. 2211400100023 METHOD (TOF) Three different methods were applied. 2211400100024 (COINC) 2211400100025 I. Double time-of-flight measurement of coincident 2211400100026 fission fragments. 2211400100027 Ii. Double energy measurement of coincident fission 2211400100028 fragments. 2211400100029 Iii. Time-of-flight/energy measurements of single 2211400100030 fission fragments. 2211400100031 DETECTOR (MWPC) Fission fragments were detected with five 2211400100032 10.2 X 10.2 cm parallel plate avalanche counters, 2211400100033 having a position resolution of +/-0.8 mm. They were 2211400100034 placed at a distance of 40 cm from the target and at 2211400100035 angles of 0, 45, +/-90, -107 and -135 degrees with 2211400100036 respect to the proton beam direction. These detectors 2211400100037 were used for method I and iii. 2211400100038 (SIBAR) Two 900 mm2 and three 300 mm2 F-series ortec 2211400100039 surface barrier detectors measured time-of-flight and 2211400100040 energy of the fragments. They were placed at angles of2211400100041 17, 73, -107, -118 and - 148 degrees. These detectors 2211400100042 were used for method ii and iii. 2211400100043 .The time reference signal for all the detectors was 2211400100044 provided by a one channel plate arrangement, placed 2211400100045 perpendicular to the target out of the reaction plane.2211400100046 Electrons knocked out from the target were deflected 2211400100047 to the detector with an electrostatic mirror. By the 2211400100048 position read-out the reaction point in the target 2211400100049 could be determined with a resolution of +/-1.5 mm. 2211400100050 MONITOR (98-CF-252(0,F),,KE,FF) 2211400100051 SAMPLE .In the first set of measurements the fission target 2211400100052 was stacked from four 140 micro-g/cm2 thf4 layers, 2211400100053 each evaporated onto 25 micro-g/cm2 carbon foil. In 2211400100054 the second set it was a face-to-face sandwich of two 2211400100055 510 micro-g/cm2 thf4 layers on 50 micro-g/cm2 carbon. 2211400100056 The targets were located 42 mm from the neutron 2211400100057 producing target. 2211400100058 CORRECTION .The data were corrected for energy losses in the 2211400100059 target. 2211400100060 ERR-ANALYS (DATA-ERR) No details given. 2211400100061 STATUS (TABLE) Data taken from main ref. 2211400100062 HISTORY (19891207C) N.O. 2211400100063 (19891211E) 2211400100064 (20090401A) Date and BIB information are corrected 2211400100065 Upper case to low case converted 2211400100066 ENDBIB 64 0 2211400100067 NOCOMMON 0 0 2211400100068 ENDSUBENT 67 0 2211400199999 SUBENT 22114002 20090401 22112211400200001 BIB 3 8 2211400200002 REACTION (90-TH-232(N,F),PRE,AP,HF) 2211400200003 FLAG (1.) Method I, where the average velocities from an 2211400200004 event-by-event evaluation were used in the analysis. 2211400200005 (2.) Method I, where the ensemble average velocities of2211400200006 the light and heavy fragment distributions were used 2211400200007 separately. 2211400200008 (3.) Method II. 2211400200009 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400200010 ENDBIB 8 0 2211400200011 NOCOMMON 0 0 2211400200012 DATA 5 6 2211400200013 EN EN-RSL DATA DATA-ERR FLAG 2211400200014 MEV MEV NO-DIM NO-DIM NO-DIM 2211400200015 1.69 1.E-02 1.401E+02 3.E-01 1. 2211400200016 1.69 1.E-02 1.401E+02 2.E-01 2. 2211400200017 1.69 1.E-02 1.381E+02 8.E-01 3. 2211400200018 1.69 2.E-02 1.401E+02 2.4 1. 2211400200019 1.69 2.E-02 1.401E+02 2.5 2. 2211400200020 1.69 2.E-02 1.399E+02 1.2 3. 2211400200021 ENDDATA 8 0 2211400200022 ENDSUBENT 21 0 2211400299999 SUBENT 22114003 20090401 22112211400300001 BIB 3 3 2211400300002 REACTION (90-TH-232(N,F),SEC,AP,HF) 2211400300003 FLAG (4.) Method III. 2211400300004 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400300005 ENDBIB 3 0 2211400300006 NOCOMMON 0 0 2211400300007 DATA 5 2 2211400300008 EN EN-RSL DATA DATA-ERR FLAG 2211400300009 MEV MEV NO-DIM NO-DIM NO-DIM 2211400300010 1.69 1.E-02 1.391E+02 2.7 4. 2211400300011 1.69 2.E-02 1.372E+02 9.E-01 4. 2211400300012 ENDDATA 4 0 2211400300013 ENDSUBENT 12 0 2211400399999 SUBENT 22114004 20090401 22112211400400001 BIB 3 3 2211400400002 REACTION (90-TH-232(N,F),PRE,AKE,HF) 2211400400003 FLAG (3.) Method II. 2211400400004 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400400005 ENDBIB 3 0 2211400400006 NOCOMMON 0 0 2211400400007 DATA 4 2 2211400400008 EN EN-RSL DATA-CM FLAG 2211400400009 MEV MEV MEV NO-DIM 2211400400010 1.69 1.E-02 6.7E+01 3. 2211400400011 1.69 2.E-02 6.7E+01 3. 2211400400012 ENDDATA 4 0 2211400400013 ENDSUBENT 12 0 2211400499999 SUBENT 22114005 20090401 22112211400500001 BIB 3 6 2211400500002 REACTION (90-TH-232(N,F),SEC,AKE,HF) 2211400500003 FLAG (1.) Method I, where the average velocities from an 2211400500004 event-by-event evaluation were used in the analysis. 2211400500005 (4.) Method III. 2211400500006 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400500007 SF5 = SEC added 2211400500008 ENDBIB 6 0 2211400500009 NOCOMMON 0 0 2211400500010 DATA 5 4 2211400500011 EN EN-RSL DATA-CM DATA-ERR FLAG 2211400500012 MEV MEV MEV MEV NO-DIM 2211400500013 1.69 1.E-02 6.65E+01 4.E-01 1. 2211400500014 1.69 1.E-02 6.59E+01 1.2 4. 2211400500015 1.69 2.E-02 6.4E+01 2.2 1. 2211400500016 1.69 2.E-02 6.5E+01 1. 4. 2211400500017 ENDDATA 6 0 2211400500018 ENDSUBENT 17 0 2211400599999 SUBENT 22114006 20090401 22112211400600001 BIB 3 3 2211400600002 REACTION (90-TH-232(N,F),PRE,AKE,LF) 2211400600003 FLAG (3.) Method II. 2211400600004 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400600005 ENDBIB 3 0 2211400600006 NOCOMMON 0 0 2211400600007 DATA 4 2 2211400600008 EN EN-RSL DATA-CM FLAG 2211400600009 MEV MEV MEV NO-DIM 2211400600010 1.69 1.E-02 9.82E+01 3. 2211400600011 1.69 2.E-02 9.9E+01 3. 2211400600012 ENDDATA 4 0 2211400600013 ENDSUBENT 12 0 2211400699999 SUBENT 22114007 20090401 22112211400700001 BIB 3 6 2211400700002 REACTION (90-TH-232(N,F),SEC,AKE,LF) 2211400700003 FLAG (1.) Method I, where the average velocities from an 2211400700004 event-by-event evaluation were used in the analysis. 2211400700005 (4.) Method III. 2211400700006 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400700007 SF5 = SEC added 2211400700008 ENDBIB 6 0 2211400700009 NOCOMMON 0 0 2211400700010 DATA 5 4 2211400700011 EN EN-RSL DATA-CM DATA-ERR FLAG 2211400700012 MEV MEV MEV MEV NO-DIM 2211400700013 1.69 1.E-02 9.98E+01 3.E-01 1. 2211400700014 1.69 1.E-02 9.66E+01 1.2 4. 2211400700015 1.69 2.E-02 9.63E+01 2.4 1. 2211400700016 1.69 2.E-02 9.71E+01 7.E-01 4. 2211400700017 ENDDATA 6 0 2211400700018 ENDSUBENT 17 0 2211400799999 SUBENT 22114008 20090401 22112211400800001 BIB 3 3 2211400800002 REACTION (90-TH-232(N,F),PRE,AKE,FF) 2211400800003 FLAG (3.) Method II. 2211400800004 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400800005 ENDBIB 3 0 2211400800006 NOCOMMON 0 0 2211400800007 DATA 4 2 2211400800008 EN EN-RSL DATA FLAG 2211400800009 MEV MEV MEV NO-DIM 2211400800010 1.69 1.E-02 1.66E+02 3. 2211400800011 1.69 2.E-02 1.643E+02 3. 2211400800012 ENDDATA 4 0 2211400800013 ENDSUBENT 12 0 2211400899999 SUBENT 22114009 20090401 22112211400900001 BIB 3 7 2211400900002 REACTION (90-TH-232(N,F),SEC,AKE,LF+HF) 2211400900003 Energy for the fission fragments. 2211400900004 FLAG (1.) Method I, where the average velocities from an 2211400900005 event-by-event evaluation were used in the analysis. 2211400900006 (4.) Method III. 2211400900007 HISTORY (20090401U) STATUS keyword deleted: repeated in SAN 0012211400900008 SF5 = SEC added, SF7 changed to LF+HF 2211400900009 ENDBIB 7 0 2211400900010 NOCOMMON 0 0 2211400900011 DATA 5 4 2211400900012 EN EN-RSL DATA DATA-ERR FLAG 2211400900013 MEV MEV MEV MEV NO-DIM 2211400900014 1.69 1.E-02 1.662E+02 2. 1. 2211400900015 1.69 1.E-02 1.636E+02 4. 2211400900016 1.69 2.E-02 1.601E+02 2. 1. 2211400900017 1.69 2.E-02 1.615E+02 4. 2211400900018 ENDDATA 6 0 2211400900019 ENDSUBENT 18 0 2211400999999 ENDENTRY 9 0 2211499999999