ENTRY 20074 20160907 22522007400000001 SUBENT 20074001 20160907 22522007400100001 BIB 11 44 2007400100002 INSTITUTE (2SWDFOA) 2007400100003 REFERENCE (J,NSE,16,124,196305) Main reference 2007400100004 (C,72VIENNA,,277,197211) - total neutron multiplicity 2007400100005 (3.778+/-0.060) derived from revised prompt neutron 2007400100006 multiplicity given 2007400100007 (C,61VIENNA,1,155,196103) Prelim.results 2007400100008 REL-REF (I,,H.Conde+,C,70ANL,,481,197010) Describing detector 2007400100009 corrections. 2007400100010 AUTHOR (I.Asplund-Nilsson,H.Conde,N.Starfelt) 2007400100011 TITLE An absolute measurement of nu-bar of Cf-252 2007400100012 METHOD (COINC) Measurement of coincidences between fission 2007400100013 and capture gamma rays 2007400100014 Neutron detection efficiency = 0.6905+-0.0053 2007400100015 DETECTOR (FISCH) Fission chamber mounted in centre of axial 2007400100016 tube through scintillation tank, which is a 2007400100017 (STANK) 60 cm glass bulb, filled with p-terphenyl 2007400100018 and 'POPOP' in tri-ethylbenzene, loaded with cadmium 2007400100019 octoate. Cadmium/hydrogen atomic ratio about 0.002. 2007400100020 12 photomultipliers uniformly distributed over sphere 2007400100021 surface 2007400100022 COMMENT n-detection efficiency determined by n-p scattering 2007400100023 in anthracene crystal replacing the fission chamber 2007400100024 nu-bar=1. 2007400100025 Adding the number of delayed neutrons per fission 2007400100026 0.86E-2, a total nu-bar of 3.778 +- 0.038 is obtained2007400100027 (error given in 72VIENNA,,277,7211 is wrong according 2007400100028 to private communication with author). 2007400100029 ERR-ANALYS (DATA-ERR) Uncertainty includes counting statistics, 2007400100030 estimated errors from double scattering of neutrons 2007400100031 on carbon and hydrogen or two hydrogen atoms, proton 2007400100032 escape (end effect), escape of neutrons through the 2007400100033 channel, tritium and/or air content of deuterium 2007400100034 target and pile-up corrections. 2007400100035 (ERR-1) Error in correction other then counting 2007400100036 statistics about 20%. 2007400100037 (ERR-2) Inaccuracy in fission neutron spectrum gives 2007400100038 about 0.5% 2007400100039 STATUS (TABLE) Data from priv. communication 2007400100040 HISTORY (19690808C) 2007400100041 (19710524T) from NEUDADA file 2007400100042 (19800822A) Data corrected after private communication 2007400100043 with author. 2007400100044 (20160907A) SD:Updated to new date formats,lower case. 2007400100045 Refs were swapped. BIB update. 2007400100046 ENDBIB 44 0 2007400100047 COMMON 2 3 2007400100048 ERR-1 ERR-2 2007400100049 PER-CENT PER-CENT 2007400100050 20. 0.5 2007400100051 ENDCOMMON 3 0 2007400100052 ENDSUBENT 51 0 2007400199999 SUBENT 20074002 20160907 22522007400200001 BIB 3 4 2007400200002 REACTION (98-CF-252(0,F),PR,NU) 2007400200003 PART-DET (PN,FF) Prompt neutrons and fission fragments in 2007400200004 coincidence. 2007400200005 HISTORY (19710524T) From NEUDADA file 2007400200006 ENDBIB 4 0 2007400200007 NOCOMMON 0 0 2007400200008 DATA 2 1 2007400200009 DATA DATA-ERR 2007400200010 PRT/FIS PRT/FIS 2007400200011 3.7670 0.038 2007400200012 ENDDATA 3 0 2007400200013 ENDSUBENT 12 0 2007400299999 ENDENTRY 2 0 2007499999999