ENTRY 23767 20210228 22982376700000001 SUBENT 23767001 20210228 22982376700100001 BIB 11 35 2376700100002 TITLE Measurement of the delayed-neutron multiplicity and 2376700100003 time constants in the thermal neutron induced 2376700100004 fission of 235U at ILL 2376700100005 AUTHOR (D.Foligno,P.Leconte,O.Serot,B.Geslot,G.De Izarra, 2376700100006 A.Chebboubi,A.Sardet,M.Diakaki,P.Tamagno,A.Billebaud, 2376700100007 F-R.Lecolley,T.Soldner,U.Koester,P.Mutti,A.Pepino, 2376700100008 O.Meplan,G.Kessedjian,J.-L.Lecouey,L.Mathieu, 2376700100009 N.Marie-Nourry) 2376700100010 INSTITUTE (2FR CAD,2FR GRE,2FR GRA,2FR CAE,2FR ILL) 2376700100011 REFERENCE (J,EPJ/CS,239,18006,2020) 2376700100012 #doi:10.1051/epjconf/202023918006 2376700100013 FACILITY (REAC,2FR GRE) 2376700100014 SAMPLE The target is a miniaturized fission chamber. The 2376700100015 fissile material, 210 ug of 235U has been 2376700100016 electroplated on a titanium support of 8 mm in 2376700100017 diameter. 2376700100018 DETECTOR (LONGC) The LOENIE long counter is made of two blocks 2376700100019 of polyethylene with a central hole to host the 2376700100020 target and 16 smaller holes to host the 3He 2376700100021 proportional counters. LOENIE has been designed to 2376700100022 have a flat efficiency as a function of the neutron 2376700100023 energy in the energy range 100keV - 1MeV. 2376700100024 ANALYSIS Average delayed-neutron yield as a function of time 2376700100025 after irradiation. 2376700100026 Irradiation time = 50 s 2376700100027 Average delayed-neutron yields measurement time = 200s 2376700100028 A veto time interval was added after the end of the 2376700100029 irradiation. 2376700100030 The fit of the first 500 ms of decay curve was 2376700100031 performed with the CONRAD code. 2376700100032 ERR-ANALYS (ERR-T) The total uncertainty due to the following 2376700100033 partial uncertainties: 2376700100034 (ERR-1) the detector efficiency - 1% 2376700100035 STATUS (TABLE) Table 1 EPJ Web of Conferences 239(2020)18006 2376700100036 HISTORY (20210228C) VS 2376700100037 ENDBIB 35 0 2376700100038 COMMON 1 3 2376700100039 EN 2376700100040 EV 2376700100041 0.0253 2376700100042 ENDCOMMON 3 0 2376700100043 ENDSUBENT 42 0 2376700199999 SUBENT 23767002 20210228 22982376700200001 BIB 2 4 2376700200002 REACTION (92-U-235(N,F),DL,NU) 2376700200003 ERR-ANALYS (ERR-2) the abundance and the decay constant of the 2376700200004 delayed-neutron group i - 0.9% 2376700200005 (ERR-S) counting statistics - 0.4% 2376700200006 ENDBIB 4 0 2376700200007 COMMON 3 3 2376700200008 ERR-1 ERR-2 ERR-S 2376700200009 PER-CENT PER-CENT PER-CENT 2376700200010 1. 0.9 0.4 2376700200011 ENDCOMMON 3 0 2376700200012 DATA 2 1 2376700200013 DATA ERR-T 2376700200014 PRT/FIS PER-CENT 2376700200015 1.631E-02 1.4 2376700200016 ENDDATA 3 0 2376700200017 ENDSUBENT 16 0 2376700299999 SUBENT 23767003 20210301 22982376700300001 BIB 3 15 2376700300002 REACTION ((92-U-235(N,F),DL/GRP,NU)/(92-U-235(N,F),DL,NU)) 2376700300003 ADD-RES (DECAY) Mean half-life of delayed neutron precursor: 2376700300004 without correlations T1/2 (s) = 8.93(5.72%) 2376700300005 with correlations T1/2 (s) = 8.93(0.98%) 2376700300006 COVARIANCE (XY,8,GRP-NUM,NO-DIM) 2376700300007 1. 2. 3. 4. 5. 6. 7. 8. 2376700300008 (Z,36,COR:ERR-T,PER-CENT) 2376700300009 100 2376700300010 -72.8 100 2376700300011 83.3 -85.2 100 2376700300012 -46.6 71.6 -78.3 100 2376700300013 46.2 -37.3 65.6 -81.4 100 2376700300014 -34.1 24.8 -48 65.2 -91.9 100 2376700300015 34.3 -5.2 37.8 -37.5 75.3 -88.9 100 2376700300016 -37.9 -8.2 -34 18.4 -62.2 70.2 -93.2 100 2376700300017 ENDBIB 15 0 2376700300018 COMMON 1 3 2376700300019 ERR-1 2376700300020 PER-CENT 2376700300021 1. 2376700300022 ENDCOMMON 3 0 2376700300023 DATA 3 8 2376700300024 GRP-NUM DATA ERR-T 2376700300025 NO-DIM NO-DIM PER-CENT 2376700300026 1. 3.64E-02 2.7 2376700300027 2. 1.31E-01 3.3 2376700300028 3. 1.15E-01 4.9 2376700300029 4. 1.66E-01 4.8 2376700300030 5. 3.55E-01 5.2 2376700300031 6. 6.92E-02 40.8 2376700300032 7. 8.15E-02 49.3 2376700300033 8. 4.58E-02 66.3 2376700300034 ENDDATA 10 0 2376700300035 ENDSUBENT 34 0 2376700399999 ENDENTRY 3 0 2376799999999