ENTRY 20760 19840203 00002076000000001 SUBENT 20760001 19840203 00002076000100001 BIB 16 42 2076000100002 INSTITUTE (2ZZZGEL) WITH COOPERATION OF NUCLEAR PHYSICS 2076000100003 INSTITUTE AND INFN OF CATANIA,ITALY(E.MIGNECO). 2076000100004 REFERENCE (C,75WASH,597,7510) NBS SPECIAL PUBLICATION.DATA GIVEN.2076000100005 (J,JNE,22,211,68) APPARATUS DETAILS ARE GIVEN. 2076000100006 AUTHOR (J.A.WARTENA,H.WEIGMANN,E.MIGNECO) 2076000100007 TITLE -ON SUB-BARRIER FISSION IN U-238- 2076000100008 FACILITY (LINAC) CBNM LINEAR ACCELERATOR PRODUCING ELECTRON 2076000100009 INC-SOURCE (EVAP ) FAST NEUTRON PRODUCED IN A MERCURY-COOLED 2076000100010 NATURAL URANIUM TARGET BY THE ELECTRON BEAM ARE 2076000100011 SLOWED DOWN BY A 2.8 CM THICK POLYETHYLENE SHEET OF 2076000100012 20 * 20 CM2.THE SPECTRUM OF THE MODERATED NEUTRONS AS 2076000100013 DETERMINED WITH A 10-B F3 COUNTER SHOWS IN GOOD 2076000100014 APPROXIMATION AN ENERGY DEPENDENCE LIKE E**-0.887 IN 2076000100015 THE CONSIDERED ENERGY RANGE. 2076000100016 SAMPLE .250 GRAMS DISK OF METALLIC U DEPLETED TO 0.2 PC OF 2076000100017 U-235. 2076000100018 METHOD (TOF ) NEUTRON TIME OF FLIGHT MEASUREMENTS COULD BE 2076000100019 PERFORMED AT A 30 M FLIGHTPATH WITH A NOMINAL 2076000100020 RESOLUTION OF 1.3 NSEC/M,CORRESPONDING TO AN ENERGY 2076000100021 RESOLUTION OF 0.7 AND 1.5 EV AT 720 AND 1210 EV 2076000100022 NEUTRON ENERGY,RESPECTIVELY. 2076000100023 DETECTOR (SCIN ) THE FISSION NEUTRON DETECTOR CONSISTS OF FOUR 2076000100024 LIQUID SCINTILLATION CHAMBERS FORMING A HOLLOW 2076000100025 CYLINDER WITH OUTER DIMENSIONS 38CM DIAM 18CM LENGTH, 2076000100026 AND INNER DIMENSIONS 16CM DIAM 38CM LENGTH. 2076000100027 .THE SAMPLE IS PLACED IN THE MIDDLE OF THIS CYLINDER. 2076000100028 .SCINTILLATOR LIQUID IS NE 213. 2076000100029 .DETECTOR FISSION SENSITIVITY WAS ABOUT 1/1000 FOR 2076000100030 PROMPT NEUTRON DETECTION. 2076000100031 MONITOR (92-U-235(N,F),,WID) 2076000100032 .DATA NORMALIZED BY COMPARISON TO YIELDS OBTAINED FROM 2076000100033 LOW ENERGY RESONANCES(8 TO 32EV)IN U-235. 2076000100034 PART-DET (N ) PROMPT FISSION NEUTRONS 2076000100035 COMMENT .COMPARISON WITH OTHER EXPERIMENTAL DATA. 2076000100036 STATUS .DATA GIVEN IN 75WASH. 2076000100037 HISTORY (780112C) 2076000100038 (780705E) 2076000100039 CORRECTION .DATA WERE CORRECTED FROM CAPTURE IN U-238,AND FROM 2076000100040 FISSION OF THE U-235 PRESENT IN THE SAMPLE. 2076000100041 .RESONANCE ANALYSIS TOOK ACCOUNT RESONANCE 2076000100042 SELF-SHIELDING AS WELL AS MULTIPLE SCATTERING EFFECTS.2076000100043 ERR-ANALYS .STATISTICAL ERRORS. 2076000100044 ENDBIB 42 0 2076000100045 NOCOMMON 0 0 2076000100046 ENDSUBENT 45 0 2076000199999 SUBENT 20760002 19840203 00002076000200001 BIB 3 4 2076000200002 REACTION (92-U-238(N,F),,WID) 2076000200003 STATUS .DATA TAKEN FROM 75WASH,597,1975. 2076000200004 HISTORY (780112C) 2076000200005 (780705E) 2076000200006 ENDBIB 4 0 2076000200007 NOCOMMON 0 0 2076000200008 DATA 4 18 2076000200009 EN-RES DATA DATA-MAX DATA-ERR 2076000200010 KEV MICRO-EV MICRO-EV MICRO-EV 2076000200011 6.6070E-01 2.0000E+01 2076000200012 6.9240E-01 3.0000E+01 2076000200013 7.0780E-01 2.5000E+01 2076000200014 7.2100E-01 8.5000E+02 1.3000E+02 2076000200015 7.2970E-01 1.2000E+02 2076000200016 7.5560E-01 2.0000E+02 2076000200017 7.6430E-01 4.0000E+01 2076000200018 1.1089E+00 2.4000E+01 1.0000E+01 2076000200019 1.1395E+00 4.0000E+01 1.5000E+01 2076000200020 1.1592E+00 1.0000E+02 2076000200021 1.1670E+00 2.5000E+01 1.5000E+01 2076000200022 1.1765E+00 2.3000E+01 1.2000E+01 2076000200023 1.1941E+00 2.5000E+01 1.2000E+01 2076000200024 1.2107E+00 2.5000E+02 5.0000E+01 2076000200025 1.2326E+00 4.0000E+02 2076000200026 1.2440E+00 2.0000E+01 2076000200027 1.2665E+00 2.0000E+01 2076000200028 1.2722E+00 3.0000E+01 2076000200029 ENDDATA 20 0 2076000200030 ENDSUBENT 29 0 2076000299999 ENDENTRY 2 0 2076099999999