ENTRY 31405 20100220 31443140500000001 SUBENT 31405001 20100220 31443140500100001 BIB 10 36 3140500100002 TITLE Test for the corrections in the measurement of Cf-252 3140500100003 spontaneous fission prompt neutron spectrum in low 3140500100004 energy portion 3140500100005 AUTHOR (S.L.Bao,G.Y.Tang,J.H.Fan,W.T.Cao) 3140500100006 INSTITUTE (3CPRBJG) 3140500100007 REFERENCE (C,89WASH,2,951,198904) Numerical data, after some 3140500100008 corrections still preliminary. 3140500100009 (C,88MITO,,755,198805) Preliminary, graph only. 3140500100010 (C,91BEIJIN,,73,199109) Same as 89WASH, graph only. 3140500100011 SAMPLE The Cf-252 source was made by means of transfusion in 3140500100012 vacuum on a highly polished stainless steel disc and 3140500100013 had an intensity of 3.8 * 10**3 fiss/sec. 3140500100014 DETECTOR (IOCH,SCIN) The fission fragment detector is a mini- 3140500100015 ion chamber, the neutron detector a Ne912 glass 3140500100016 detector matched with a RCA8850 phototube. The neutron 3140500100017 detector efficiency was calculated using a Monte Carlo 3140500100018 code. The result was compared with relatively measured 3140500100019 data for a detector with the same size. 3140500100020 METHOD (TOF) Flight path was 30 cm. 3140500100021 CORRECTION The following corrections were considered: 3140500100022 - scattering on preamplifier ( measured 1%). 3140500100023 - the scattering on air column between the two 3140500100024 detectors ( 0.5% as estimated by a Monte-Carlo 3140500100025 calculation). 3140500100026 - the scattering on the Cf-252 source backing 3140500100027 ( measured <1%). 3140500100028 - the scattering in the environment ( measured using 3140500100029 a shadow bar). 3140500100030 - the correction for delayed gamma-rays was 3140500100031 calculated in the time range 30 - 100 ns. 3140500100032 HISTORY (19921019C) HW 3140500100033 (20090730A) SD:Updated to new date formats,lower case. 3140500100034 Cosmetic changes 3140500100035 STATUS (TABLE) Data are taken from ' 50 years Nucl. Fission 3140500100036 Conf.', Washington D.C.,1989,p.951.Table 1 (ratio's) 3140500100037 and the text ( av. kin. energy). 3140500100038 ENDBIB 36 0 3140500100039 NOCOMMON 0 0 3140500100040 ENDSUBENT 39 0 3140500199999 SUBENT 31405002 20100220 31443140500200001 BIB 3 9 3140500200002 REACTION (98-CF-252(0,F)0-NN-1,PR,KEM) 3140500200003 ANALYSIS The measured spectrum was fitted by a Maxwellian 3140500200004 distribution. 3140500200005 ERR-ANALYS Source of uncertainty uncertainty % 3140500200006 ----------------------------------------------------- 3140500200007 (ERR-S) counting statistics 4. 3140500200008 (ERR-1) detector efficiency calculation 6. 3140500200009 (ERR-2) transformation from time to energy scale 0.663140500200010 (ERR-3) delayed gamma-ray correction 2. 3140500200011 ENDBIB 9 0 3140500200012 NOCOMMON 0 0 3140500200013 DATA 5 1 3140500200014 DATA ERR-1 ERR-2 ERR-3 ERR-S 3140500200015 MEV PER-CENT PER-CENT PER-CENT PER-CENT 3140500200016 1.42 4. 6. 0.66 2. 3140500200017 ENDDATA 3 0 3140500200018 ENDSUBENT 17 0 3140500299999 SUBENT 31405003 20100220 31443140500300001 BIB 2 8 3140500300002 REACTION (98-CF-252(0,F),PR,NU/DE,,MXD) Relative to Maxwell 3140500300003 spectrum with av. kin. energy of 2.13 MeV. 3140500300004 ERR-ANALYS (ERR-T) The uncertainties of the results consisted of: 3140500300005 (ERR-S) the statistical uncertainty, 3140500300006 (ERR-1) the uncertainty from the prompt-neutron 3140500300007 detector efficiency calculation ( 6%), 3140500300008 (ERR-2) uncertainty caused by the efficiency 3140500300009 curve shape factor. 3140500300010 ENDBIB 8 0 3140500300011 COMMON 2 3 3140500300012 ERR-1 KT-NRM 3140500300013 PER-CENT MEV 3140500300014 6.0 1.42 3140500300015 ENDCOMMON 3 0 3140500300016 DATA 5 33 3140500300017 E DATA ERR-S ERR-2 ERR-T 3140500300018 KEV NO-DIM PER-CENT PER-CENT PER-CENT 3140500300019 148.70 0.88 3.46 5.39 8.78 3140500300020 154.89 0.95 3.14 6.24 9.21 3140500300021 161.47 0.93 3.03 6.82 9.58 3140500300022 168.48 0.96 2.75 7.15 9.72 3140500300023 175.96 1.02 2.44 7.38 9.82 3140500300024 183.95 0.99 2.30 7.56 9.93 3140500300025 192.49 1.06 2.02 8.11 10.29 3140500300026 201.65 1.09 1.80 8.32 10.42 3140500300027 211.47 1.09 1.61 8.44 10.49 3140500300028 222.03 1.06 1.46 8.36 9.70 3140500300029 233.40 1.01 1.37 4.97 7.91 3140500300030 245.67 1.00 1.31 2.29 6.43 3140500300031 258.93 0.97 1.32 1.69 6.37 3140500300032 273.29 0.99 1.35 2.61 7.00 3140500300033 288.88 0.98 1.42 3.75 7.21 3140500300034 305.85 0.99 1.48 3.73 7.22 3140500300035 324.35 1.02 1.52 3.43 7.07 3140500300036 344.59 1.00 1.60 2.68 6.76 3140500300037 366.78 0.99 1.65 1.68 6.45 3140500300038 391.19 0.94 1.72 1.24 6.37 3140500300039 418.11 0.88 1.79 2.21 6.64 3140500300040 447.92 0.91 1.85 3.00 6.96 3140500300041 481.03 0.93 1.87 2.00 6.60 3140500300042 517.95 0.96 1.87 0.99 6.37 3140500300043 559.29 0.95 1.85 1.10 6.39 3140500300044 605.78 0.95 1.81 1.48 6.39 3140500300045 658.33 0.96 1.77 1.48 6.43 3140500300046 718.02 0.99 1.69 1.80 6.49 3140500300047 786.20 1.00 1.62 1.96 6.52 3140500300048 864.59 0.99 1.56 2.23 6.59 3140500300049 955.31 0.99 1.50 1.60 6.39 3140500300050 1061.09 1.04 1.42 1.73 6.41 3140500300051 1185.47 1.06 1.35 2.91 6.49 3140500300052 ENDDATA 35 0 3140500300053 ENDSUBENT 52 0 3140500399999 ENDENTRY 3 0 3140599999999