ENTRY 30347 20090115 31343034700000001 SUBENT 30347001 20090115 31343034700100001 BIB 16 40 3034700100002 INSTITUTE (3AULAUA) Second author 3034700100003 (3INDTRM) First author 3034700100004 REFERENCE (J,NP/A,144,1,197003) 3034700100005 AUTHOR (N.N.Ajitanand,J.W.Boldeman) 3034700100006 TITLE Precise measurements of the average kinetic energy of 3034700100007 fragments in the fission of U-235 by fast neutrons 3034700100008 FACILITY (VDG,3AULAUA) 3034700100009 INC-SOURCE (P-LI7) 3034700100010 SAMPLE 15 micro-g/cm2 of 93% enriched U-235 electro- 3034700100011 deposited on gold(17 micro-g/cm2) and resin(10 micro-g/3034700100012 cm2) coated VYNS plastic film(45 micro-g/cm2) 3034700100013 METHOD (COINC) Fast coincidence between two fission 3034700100014 fragment detectors. Each run using fast 3034700100015 neutrons was preceded and followed by a 3034700100016 run using neutrons thermalised by passage 3034700100017 through 7 cm of polyethylene. 3034700100018 DETECTOR (SOLST) Two solid-state surface barrier detectors 3034700100019 ANALYSIS -Light and heavy fragment distribution for the thermal 3034700100020 runs preceding and following each fast run were fitted3034700100021 with gaussian curves. Average channel width in energy 3034700100022 units was determined from the known difference between3034700100023 the light and heavy fragment average kinetic energies 3034700100024 in thermal fission of U-235. 3034700100025 -The difference between the average of the fast pulse 3034700100026 height sum distribution and the average of the 3034700100027 preceding and following thermal sum distributions was 3034700100028 converted to energy units using the above calibration.3034700100029 MONITOR No information 3034700100030 PART-DET (FF) 3034700100031 STATUS (TABLE) Data taken from Nucl.Phys.A144(1970)1,Table 1. 3034700100032 HISTORY (19850807C) DG.- 3034700100033 (20090125A) BIB section updated 3034700100034 CORRECTION -Center of mass motion -- negligible 3034700100035 -Fraction of fission events caused by neutrons 3034700100036 inelastically scattered from surroundings -- shown 3034700100037 to be less than 2% by pulsing the accelerator 3034700100038 and observing the time distribution of fissions 3034700100039 -See also (MISC2) and (MISC3) 3034700100040 ERR-ANALYS (DATA-ERR) includes statistical errors and errors due 3034700100041 to finite width. 3034700100042 ENDBIB 40 0 3034700100043 NOCOMMON 0 0 3034700100044 ENDSUBENT 43 0 3034700199999 SUBENT 30347002 20090115 31343034700200001 BIB 3 16 3034700200002 REACTION (92-U-235(N,F),,AKE,FF,MSC) 3034700200003 Difference between the average kinetic energy of 3034700200004 fission fragments from fast-neutron induced fission 3034700200005 and the same average from thermal-neutron fission. 3034700200006 MISC-COL (MISC1) Uncorrected weighted average of all fast 3034700200007 runs at the same incident neutron energy 3034700200008 (MISC2) Correction for energy-loss in target and in 3034700200009 gold surface of the detector. Dependent on 3034700200010 anisotropy of the fragment angular distribution3034700200011 (MISC3) Correction for decrease in the total kinetic 3034700200012 energy because of the decreased mass of the 3034700200013 fragments due to neutron emission. 3034700200014 COMMENT Author comment: No significant dependence of the 3034700200015 average total fission fragment kinetic energy on the 3034700200016 excitation of the fissioning nucleus and no indication 3034700200017 of channel effects,within experimental error. 3034700200018 ENDBIB 16 0 3034700200019 NOCOMMON 0 0 3034700200020 DATA 7 9 3034700200021 EN EN-RSL DATA DATA-ERR MISC1 MISC2 3034700200022 MISC3 3034700200023 KEV KEV MEV MEV MEV MEV 3034700200024 MEV 3034700200025 2.0000E+02 2.0000E+01-1.0000E-01 2.1000E-01-1.0500E-01-1.6000E-023034700200026 1.7000E-02 3034700200027 3.0000E+02 1.7000E+01 2.6000E-01 2.0000E-01 2.5200E-01-2.2000E-023034700200028 2.6000E-02 3034700200029 3.5000E+02 1.5000E+01 5.0000E-02 1.8000E-01 4.1000E-02-2.5000E-023034700200030 3.0000E-02 3034700200031 4.0000E+02 1.5000E+01 1.9000E-01 1.9000E-01 1.9200E-01-2.8000E-023034700200032 3.4000E-02 3034700200033 4.5000E+02 1.5000E+01-5.0000E-02 2.0000E-01-5.8000E-02-3.1000E-023034700200034 3.8000E-02 3034700200035 5.0000E+02 1.5000E+01-1.2000E-01 2.1000E-01-1.3500E-01-3.4000E-023034700200036 4.3000E-02 3034700200037 6.0000E+02 1.5000E+01 1.3000E-01 2.0000E-01 1.1600E-01-4.0000E-023034700200038 5.1000E-02 3034700200039 7.0000E+02 1.5000E+01-5.0000E-02 2.4000E-01-6.6000E-02-4.5000E-023034700200040 6.0000E-02 3034700200041 9.0000E+02 1.5000E+01-3.0000E-02 2.5000E-01-5.3000E-02-5.6000E-023034700200042 7.7000E-02 3034700200043 ENDDATA 22 0 3034700200044 ENDSUBENT 43 0 3034700299999 ENDENTRY 2 0 3034799999999