ENTRY 41758 20230828 421441758 0 1 SUBENT 41758001 20230828 421441758 1 1 BIB 12 58 41758 1 2 TITLE Structure of the prompt neutron multiplicity 41758 1 3 distribution in the spontaneous fission of 256Rf 41758 1 4 AUTHOR (A.V.Isaev,R.S.Mukhin,A.V.Andreev,Z.Asfari, 41758 1 5 M.L.Chelnokov,V.I.Chepigin,H.M.Devaraja,O.Dorvaux, 41758 1 6 B.Gall,K.Hauschild,I.N.Izosimov,A.A.Kuznetsova, 41758 1 7 A.Lopez-Martens,O.N.Malyshev,A.G.Popeko,Yu.A.Popov, 41758 1 8 A.Rahmatinejad,B.Sailaubekov,T.M.Shneidman,E.A.Sokol, 41758 1 9 A.I.Svirikhin,M.S.Tezekbayeva,A.V.Yeremin, 41758 1 10 N.I.Zamyatin) 41758 1 11 INSTITUTE (4ZZZDUB) A.V.Isaev,R.S.Mukhin,A.V.Andreev, 41758 1 12 M.L.Chelnokov,V.I.Chepigin,H.M.Devaraja,I.N.Izosimov, 41758 1 13 A.A.Kuznetsova,O.N.Malyshev,A.G.Popeko,Yu.A.Popov, 41758 1 14 A.Rahmatinejad,B.Sailaubekov,T.M.Shneidman,E.A.Sokol, 41758 1 15 A.I.Svirikhin,M.S.Tezekbayeva,A.V.Yeremin, 41758 1 16 N.I.Zamyatin 41758 1 17 (2FR STR)Z.Asfari,O.Dorvaux,B.Gall 41758 1 18 (2FR PAR)K.Hauschild, A.Lopez-Martens 41758 1 19 (4RUSDBU) O.N.Malyshev,A.G.Popeko,Yu.A.Popov, 41758 1 20 A.I.Svirikhin,A.V.Yeremin 41758 1 21 (4KASKAZ) B.Sailaubekov,M.S.Tezekbayeva 41758 1 22 (4KASATN) B.Sailaubekov, 41758 1 23 (4RUSRUS) Kazan Federal University, Kazan, Russia. 41758 1 24 T.M.Shneidman 41758 1 25 REFERENCE (J,PL/B,843,138008,2023) 41758 1 26 #doi:10.1016/j.physletb.2023.138008 41758 1 27 FACILITY (CYCLO,4ZZZDUB) U-400 cyclotron 41758 1 28 SHELS velocity filter = modernized 41758 1 29 VASSILISSA electrostatic separator. 41758 1 30 SAMPLE 208PbS (thickness 350 microg/cm2, Pb-208 isotope 41758 1 31 enrichment > 99 %) was irradiated with a beam (up to 41758 1 32 237+-3 MeV energy) of charged 50-Ti ions. 41758 1 33 The total number of beam ions that passed through the 41758 1 34 target and then stopped in a faraday cup was about 41758 1 35 2.8*10**18. 41758 1 36 Rf-256 nuclei were separated by SHELS filter. 41758 1 37 DETECTOR (SISD,HE3SP) 54 He-3 neutron detectors placed around 41758 1 38 an assembly of Si detectors consisting of a 48x48-strip41758 1 39 focal-plane detector and 4 tunnel 16-strip detectors 41758 1 40 for fission fragments and alpha-particle registration. 41758 1 41 The neutron detector efficiency measured with a 248Cm 41758 1 42 source was (45 +- 1)%. 41758 1 43 Average neutron life-time in the assembly is 41758 1 44 (23+-1) microsec . 41758 1 45 DECAY-DATA (104-RF-256,6.7E-3SEC) 6.7+-0.2 msec, measured. 41758 1 46 METHOD Fission fragments from Rf-256 spontaneous fission were41758 1 47 searched for the time interval (0 - 62) msec (~10*T1/2)41758 1 48 following the registration of the implanted reaction 41758 1 49 products. 41758 1 50 Total number of 2605 prompt neutrons in correlation 41758 1 51 with 1345 256Rf spontaneous fission events were 41758 1 52 registered. 41758 1 53 Neutron signals were separated from gamma-quanta 41758 1 54 signals by setting the thresholds of discriminators. 41758 1 55 CORRECTION Background neutron counting rate was ~100 neutrons/s 41758 1 56 inside the detector. 41758 1 57 ADD-RES (DECAY) the alpha decay branching ratio was found to be41758 1 58 0.003 +0.005 -0.003. 41758 1 59 HISTORY (20230828C) M.M. 41758 1 60 ENDBIB 58 0 41758 1 61 NOCOMMON 0 0 41758 1 62 ENDSUBENT 61 0 41758 199999 SUBENT 41758002 20230828 421441758 2 1 BIB 4 6 41758 2 2 REACTION (104-RF-256(0,F),PR,NU) 41758 2 3 MISC-COL (MISC) Variance of neutron distribution 41758 2 4 ERR-ANALYS (ERR-S) Statistical uncertainty. 41758 2 5 STATUS (TABLE,,A.V.Isaev+,J,PL/B,843,138008,2023) 41758 2 6 Text in chapter 3.Results. 41758 2 7 (DEP,41758003) Prompt neutron distribution. 41758 2 8 ENDBIB 6 0 41758 2 9 NOCOMMON 0 0 41758 2 10 DATA 3 1 41758 2 11 DATA ERR-S MISC 41758 2 12 PRT/FIS PRT/FIS SEE TEXT 41758 2 13 4.30 0.17 3.2 41758 2 14 ENDDATA 3 0 41758 2 15 ENDSUBENT 14 0 41758 299999 SUBENT 41758003 20230828 421441758 3 1 BIB 4 10 41758 3 2 REACTION (104-RF-256(0,F),PR/NUM,NU) 41758 3 3 MISC-COL (MISC1) Distribution of multiplicity of detected prompt41758 3 4 neutrons, normalized to 1. 41758 3 5 (MISC2) Number of observed spontaneous fission events. 41758 3 6 ERR-ANALYS (ERR-S) Statistical uncertainty. 41758 3 7 (MISC1-ERR) Statistical uncertainty. 41758 3 8 For PART-OUT = 7 and 8 the value is < 0.001 in 41758 3 9 the Table 1. 41758 3 10 STATUS (TABLE,,A.V.Isaev+,J,PL/B,843,138008,2023) 41758 3 11 Table 1 . 41758 3 12 ENDBIB 10 0 41758 3 13 NOCOMMON 0 0 41758 3 14 DATA 6 9 41758 3 15 PART-OUT DATA ERR-S MISC1 MISC1-ERR MISC2 41758 3 16 NO-DIM NO-DIM NO-DIM NO-DIM NO-DIM SEE TEXT 41758 3 17 0. 0.042 0.014 0.148 0.010 199. 41758 3 18 1. 0.062 0.018 0.259 0.014 348. 41758 3 19 2. 0.062 0.021 0.255 0.010 343. 41758 3 20 3. 0.102 0.021 0.215 0.007 290. 41758 3 21 4. 0.192 0.022 0.096 0.004 129. 41758 3 22 5. 0.253 0.022 0.024 0.002 32. 41758 3 23 6. 0.205 0.019 0.002 0.001 3. 41758 3 24 7. 0.082 0.018 0.001 1. 41758 3 25 8. 0. 0.014 0. 0. 41758 3 26 ENDDATA 11 0 41758 3 27 ENDSUBENT 26 0 41758 399999 ENDENTRY 3 0 4175899999999