ENTRY 10930 20170822 143310930 0 1 SUBENT 10930001 20170822 143310930 1 1 BIB 10 33 10930 1 2 TITLE Prompt Neutron Multiplicity Distribution in the 10930 1 3 Spontaneous Fission of Curium-242 10930 1 4 AUTHOR (J.Halperin,C.E.Bemis JR,J.W.T.Dabbs,B.H.Ketelle, 10930 1 5 R.W.Stoughton,R.W.Hoff,R.J.Dougan) 10930 1 6 REFERENCE (J,NSE,75,56,1980) 10930 1 7 (J,BAP,25,487,1980) 10930 1 8 INSTITUTE (1USAORL,1USALRL) 10930 1 9 DETECTOR (PROPC) Fission neutrons counted with 30 helium-3 10930 1 10 detectors, 2.5-cm diameter, 60-cm long, 6-atm 10930 1 11 pressure, embedded in a cylindrical paraffin and 10930 1 12 polyethylene matrix, 54-cm diameter, 90-cm long. 10930 1 13 (FISCH) Gas filled counter with hemispherical 10930 1 14 geometry. Active sample deposited on convex surface, 10930 1 15 electron charge collected on concentric surface 2-mm 10930 1 16 from source. 10930 1 17 METHOD (COINC) Fission chamber inserted into a 10-cm 10930 1 18 diameter hole that penetrates central core of 10930 1 19 paraffin-polyethylene cylinder. Helium-3 counters 10930 1 20 placed parallel to cylinder axis, spaced symmetrically 10930 1 21 into 3 concentric rings. Fission of known Cf-252 10930 1 22 sample used to calibrate He-3 counters. A pulse from 10930 1 23 a fission chamber serves to open a gate to count 10930 1 24 nearly all neutrons detected in coincidence with the 10930 1 25 fission fragment. 10930 1 26 MONITOR (98-CF-252(0,F),PR,NU) 10930 1 27 CORRECTION Corrections made for background neutrons and 10930 1 28 accidentals. Contributions to spontaneous fission 10930 1 29 rates by impurities not corrected for. 10930 1 30 STATUS (APRVD) Approved by J.Halperin, 1981/2/12. 10930 1 31 HISTORY (19801201C) 10930 1 32 (20170822A) BP: Updated to new date formats,lower 10930 1 33 case. Corrections according last EXFOR rules and 10930 1 34 Dict. Added fission neutron multiplicity distribution. 10930 1 35 ENDBIB 33 0 10930 1 36 COMMON 1 3 10930 1 37 MONIT 10930 1 38 PRT/FIS 10930 1 39 3.760 10930 1 40 ENDCOMMON 3 0 10930 1 41 ENDSUBENT 40 0 10930 199999 SUBENT 10930002 20170822 143310930 2 1 BIB 6 9 10930 2 2 REACTION (96-CM-242(0,F),PR,NU) 10930 2 3 SAMPLE Cm-242 formed from the radioactive decay of Am-242. 10930 2 4 ERR-ANALYS (DATA-ERR) Quoted error includes counting statistics 10930 2 5 and systematic uncertainties. 10930 2 6 DECAY-DATA (95-AM-242-G,16.02HR,B-) 10930 2 7 (96-CM-242,162.8D,A) 10930 2 8 STATUS (TABLE) page 59. 10930 2 9 HISTORY (19820108A) Corrected reaction, monitor. 10930 2 10 (20170822A) BP: Corrected units. 10930 2 11 ENDBIB 9 0 10930 2 12 NOCOMMON 0 0 10930 2 13 DATA 2 1 10930 2 14 DATA DATA-ERR 10930 2 15 PRT/FIS PRT/FIS 10930 2 16 2.532 0.013 10930 2 17 ENDDATA 3 0 10930 2 18 ENDSUBENT 17 0 10930 299999 SUBENT 10930003 20170822 143310930 3 1 BIB 7 8 10930 3 2 REACTION (96-CM-242(0,F),PR/NUM,NU) 10930 3 3 SAMPLE Cm-242 formed from the radioactive decay of Am-242. 10930 3 4 ERR-ANALYS (ERR-S) Counting statistics only. 10930 3 5 FLAG (1.) Multiplicity 7 is used for 7 and more neutrons. 10930 3 6 DECAY-DATA (95-AM-242-G,16.02HR,B-) 10930 3 7 (96-CM-242,162.8D,A) 10930 3 8 STATUS (TABLE) Table II, page 59. 10930 3 9 HISTORY (20170822C) BP 10930 3 10 ENDBIB 8 0 10930 3 11 NOCOMMON 0 0 10930 3 12 DATA 4 8 10930 3 13 PART-OUT DATA ERR-S FLAG 10930 3 14 NO-DIM NO-DIM NO-DIM NO-DIM 10930 3 15 0. 0.27695 0.00069 10930 3 16 1. 0.41220 0.00084 10930 3 17 2. 0.23595 0.00064 10930 3 18 3. 0.06498 0.00033 10930 3 19 4. 0.008559 0.000115 10930 3 20 5. 0.000549 0.000026 10930 3 21 6. 0.000016 0.000004 10930 3 22 7. 0.0000002 0.0000002 1. 10930 3 23 ENDDATA 10 0 10930 3 24 ENDSUBENT 23 0 10930 399999 SUBENT 10930004 20170822 143310930 4 1 BIB 6 8 10930 4 2 REACTION (98-CF-252(0,F),PR/NUM,NU) 10930 4 3 SAMPLE (98-CF-252,ENR=0.995) Isotopically pure 252Cf was 10930 4 4 deposited with an ion accelerator 400 A beneath the 10930 4 5 surface of an aluminum foil. 10930 4 6 ERR-ANALYS (ERR-S) Counting statistics only. 10930 4 7 FLAG (1.) Multiplicity 7 is used for 7 and more neutrons. 10930 4 8 STATUS (TABLE) Table II, page 59. 10930 4 9 HISTORY (20170822C) BP 10930 4 10 ENDBIB 8 0 10930 4 11 NOCOMMON 0 0 10930 4 12 DATA 4 8 10930 4 13 PART-OUT DATA ERR-S FLAG 10930 4 14 NO-DIM NO-DIM NO-DIM NO-DIM 10930 4 15 0. 0.14366 0.00072 10930 4 16 1. 0.33167 0.00109 10930 4 17 2. 0.31444 0.00107 10930 4 18 3. 0.15708 0.00075 10930 4 19 4. 0.04453 0.00040 10930 4 20 5. 0.00723 0.00015 10930 4 21 6. 0.000644 0.000040 10930 4 22 7. 0.000026 0.000007 1. 10930 4 23 ENDDATA 10 0 10930 4 24 ENDSUBENT 23 0 10930 499999 ENDENTRY 4 0 1093099999999