ENTRY 31443 20100306 31443144300000001 SUBENT 31443001 20100306 31443144300100001 BIB 13 47 3144300100002 TITLE Experimental study of the prompt neutron spectra 3144300100003 fission induced by fast neutrons. 3144300100004 AUTHOR (Li Anli,Bai Xixiang,Wang Xiaozhong,Wang Yufeng, 3144300100005 Meng Jiangchen,Liu Weiping,Yuan Yuan,Chih Tahai, 3144300100006 Huang Shengnian) 3144300100007 INSTITUTE (3CPRAEP) 3144300100008 REFERENCE (J,CNP,16,(3),255,1994) 3144300100009 (J,CNST,5,(2),71,199405) experimental details only. 3144300100010 FACILITY (VDG,3CPRAEP) IAE Van der Graaff Accelerator. 3144300100011 INC-SOURCE (D-D) Neutrons were produced by bombarding a deuterium 3144300100012 gas cell ( 4.3 atm.) with a 7.4 MeV pulsed deuteron 3144300100013 beam. 3144300100014 SAMPLE Natural uranium electro-deposited on both sides of 3144300100015 0.2 mm thick plates of stainless steel with deposition 3144300100016 thickness of about 0.5 mg/cm**2. 3144300100017 DETECTOR (IOCH,SCIN) Fission fragments were detected by a 3144300100018 paralell-plate ionization chamber which operated in 3144300100019 multi-segment mode and was filled with pure methane at 3144300100020 a pressure of 4.3 atm. Fission neutrons were detected 3144300100021 by two liquid scintillators both placed at 100 degrees 3144300100022 with respect to the incident neutron beam and at 2.3 m 3144300100023 from the ionization chamber. 3144300100024 METHOD (TOF,COINC,PSD) The incident-neutron tof spectrum was 3144300100025 obtained from the fission-fragment event signals with 3144300100026 the pulsed-beam tof method. A liquid scintillator, 3144300100027 located at 0 deg. and 3.1 m down stream of the gas 3144300100028 cell served as monitor of the incident-neutron Tof 3144300100029 spectrum. Fission neutrons were selected by requiring 3144300100030 coincidence between neutron detector- and fission- 3144300100031 fragment detector events which also provided the 3144300100032 fission-neutron tof spectra. Events induced by the 3144300100033 10.17 and 12.12 MeV incident neutrons were software 3144300100034 selected by gating the tof spectrum of secundary neu- 3144300100035 trons with the 10.17 and 12.12 MeV peaks of the in- 3144300100036 cident-neutron spectra. Pulse-shape discrimination was 3144300100037 applied to eliminate gamma-ray background. 3144300100038 ANALYSIS The measured spectrum was fitted by a Maxwellian 3144300100039 distribution. 3144300100040 ERR-ANALYS (DATA-ERR) The error refers to the uncertainties due to3144300100041 counting statistics and determination of detector 3144300100042 efficiency. 3144300100043 HISTORY (19941107C) HW 3144300100044 (20100219A) SD:Updated to new date formats,lower case. 3144300100045 (20100303A) SD: REACTION code in Subent 002 was changed3144300100046 according to EXFOR rules. 3144300100047 STATUS (TABLE) Data are taken from Table 1 of Chin. Journ. of 3144300100048 Nucl. Phys. Vol. 16., No. 3, 1994, pp. 255-262. 3144300100049 ENDBIB 47 0 3144300100050 NOCOMMON 0 0 3144300100051 ENDSUBENT 50 0 3144300199999 SUBENT 31443002 20100306 31443144300200001 BIB 2 3 3144300200002 REACTION (92-U-238(N,F)0-NN-1,PR,KE) 3144300200003 HISTORY (20100303A) SD: REACTION code was changed 3144300200004 according to EXFOR rules. 3144300200005 ENDBIB 3 0 3144300200006 NOCOMMON 0 0 3144300200007 DATA 3 2 3144300200008 EN DATA DATA-ERR 3144300200009 MEV MEV MEV 3144300200010 10.17 2.10 0.06 3144300200011 12.12 2.21 0.06 3144300200012 ENDDATA 4 0 3144300200013 ENDSUBENT 12 0 3144300299999 ENDENTRY 2 0 3144399999999