ENTRY 41751 20220720 42074175100000001 SUBENT 41751001 20220720 42074175100100001 BIB 9 45 4175100100002 TITLE Prompt neutron emission in the spontaneous fission of 4175100100003 246Fm 4175100100004 AUTHOR (A.V.Isaev,R.S.Mukhin,A.V.Andreev,M.A.Bychkov, 4175100100005 M.L.Chelnokov,V.I.Chepigin,H.M.Devaraja,O.Dorvaux, 4175100100006 M.Forge,B.Gall,K.Hauschild,I.N.Izosimov,K.Kessaci, 4175100100007 A.A.Kuznetsova,A.Lopez-Martens,O.N.Malyshev, 4175100100008 A.G.Popeko,Yu.A.Popov,A.Rahmatinejad,B.Sailaubekov, 4175100100009 T.M.Shneidman,E.A.Sokol,A.I.Svirikhin,D.A.Testov, 4175100100010 M.S.Tezekbayeva,A.V.Yeremin,N.I.Zamyatin, 4175100100011 K.Sh.Zhumadilov) 4175100100012 INSTITUTE (4ZZZDUB) A.V.Isaev,R.S.Mukhin,A.V.Andreev,M.A.Bychkov,4175100100013 M.L.Chelnokov,V.I.Chepigin,H.M.Devaraja,I.N.Izosimov, 4175100100014 A.A.Kuznetsova,O.N.Malyshev,A.G.Popeko,,Yu.A.Popov, 4175100100015 A.Rahmatinejad,B.Sailaubekov,T.M.Shneidman,E.A.Sokol, 4175100100016 A.I.Svirikhin,D.A.Testov,M.S.Tezekbayeva,A.V.Yeremin. 4175100100017 (2FR STR) O.Dorvaux,M.Forge,B.Gall,K.Kessaci. 4175100100018 (2FR SAC) K.Hauschild,A.Lopez-Martens. 4175100100019 (4RUSDBU) Dubna State University, Dubna, Russia. 4175100100020 O.N.Malyshev,A.G.Popeko,Yu.A.Popov,A.I.Svirikhin, 4175100100021 A.V.Yeremin. 4175100100022 (4KASKAZ) B.Sailaubekov,M.S.Tezekbayeva. 4175100100023 (4KASATN) B.Sailaubekov,K.Sh.Zhumadilov. 4175100100024 (4RUSRUS) Kazan' Federal University, Kazan', Russia. 4175100100025 T.M.Shneidman. 4175100100026 REFERENCE (J,EPJ/A,58,108,2022) 4175100100027 #doi:10.1140/epja/s10050-022-00761-3 4175100100028 REL-REF (I,,A.G.Popeko+,J,NIM/B,376,140,2016) 4175100100029 Separator SHELS 4175100100030 (I,,A.V.Isaev+,J,PPN/L,19,37,2022) 4175100100031 SFiNx detection system 4175100100032 FACILITY (CYCLO,4ZZZDUB) FLNR Dubna U-400 cyclotron for sample 4175100100033 production. 4175100100034 DETECTOR (HE3SP) 116 He-3 filled counters for prompt neutrons. 4175100100035 The neutron registration efficiency, measured with a 4175100100036 248Cm source, is (54.8 +- 0.1)%. 4175100100037 (SISD) Double-sided Si detectors with 128x128-strip 4175100100038 focal-plane detector and 8 tunnel 16x16-strip detectors4175100100039 for fission-fragment and alpha-particle registration. 4175100100040 The detection efficiency of the focal-plane Si detector4175100100041 for alpha-particles emitted by implanted nuclei is ~50%4175100100042 and 100% for at least one of the two fission fragments.4175100100043 ERR-ANALYS (ERR-S) Relative statistical uncertainty ~ 8 %. 4175100100044 (DATA-ERR) Type of uncertainty is not explained in the 4175100100045 article. 4175100100046 HISTORY (20220720C) M.M. 4175100100047 ENDBIB 45 0 4175100100048 COMMON 1 3 4175100100049 ERR-S 4175100100050 PER-CENT 4175100100051 8. 4175100100052 ENDCOMMON 3 0 4175100100053 ENDSUBENT 52 0 4175100199999 SUBENT 41751002 20220720 42074175100200001 BIB 8 21 4175100200002 REACTION (100-FM-246(0,F),PR,NU) 4175100200003 Average number of prompt neutrons. 4175100200004 REL-REF (A,41539002,A.I.Svirikhin+,J,EPJ/A,44,393,2010) 4175100200005 3.55 +- 0.50 n/fis. 4175100200006 (A,,R.S.Mukhin+,J,PPN/L,18,439,2021) 4175100200007 3.9+-0.9 n/fis with variance 3.1 4175100200008 SAMPLE Produced in the complete fusion reaction 4175100200009 Ar-40(Pb-208,2n)Fm-246. The 40Ar16+ ion beam energy 4175100200010 183+-3 MeV. PbS target thickness 450 microgram/cm2, 4175100200011 Pb-208 enrichment over 99 %. Total number of beam ions 4175100200012 1.7E+18. 4175100200013 DECAY-DATA (100-FM-246,1.50SEC) Measured 1.50 +0.08/-0.07 sec. 4175100200014 ADD-RES (DECAY) SF branching ratio 0.061 +- 0.005 was obtained.4175100200015 METHOD 235 Fm-246 SF events and 488 prompt neutrons were 4175100200016 registered. 2 events were assigned to Fm-244 SF. 4175100200017 3.79 +- 0.30(statistical) n/fis with variance 2.1 was 4175100200018 obtained before reconstruction by regularization 4175100200019 method ( see REL-REF of R.S.Mukhin+). 4175100200020 MISC-COL (MISC) Variance of multiplicity distribution SIG2. 4175100200021 STATUS (TABLE) Table 2 of J,EPJ/A,58,108,2022 4175100200022 (DEP,41751003) Prompt neutrons distribution. 4175100200023 ENDBIB 21 0 4175100200024 NOCOMMON 0 0 4175100200025 DATA 3 1 4175100200026 DATA DATA-ERR MISC 4175100200027 PRT/FIS PRT/FIS SEE TEXT 4175100200028 3.79 0.20 2.80 4175100200029 ENDDATA 3 0 4175100200030 ENDSUBENT 29 0 4175100299999 SUBENT 41751003 20220720 42074175100300001 BIB 8 18 4175100300002 REACTION (100-FM-246(0,F),PR/NUM,NU) 4175100300003 Probability of emission of N prompt neutrons. 4175100300004 SAMPLE Produced in the complete fusion reaction 4175100300005 Ar-40(Pb-208,2n)Fm-246. The 40Ar16+ ion beam energy 4175100300006 183+-3 MeV. PbS target thickness 450 microgram/cm2, 4175100300007 Pb-208 enrichment over 99 %. Total number of beam ions 4175100300008 1.7E+18. 4175100300009 DECAY-DATA (100-FM-246,1.50SEC) Measured 1.50 +0.08/-0.07 sec. 4175100300010 ANALYSIS The true form of the neutron multiplicity distribution4175100300011 was restored using Tikhonov's method of statistical 4175100300012 regularization ( see REL-REF of R.S.Mukhin+). 4175100300013 REL-REF (N,,R.S.Mukhin+,J,PPN/L,18,439,2021) 4175100300014 MISC-COL (MISC) Distribution of multiplicity of detected prompt 4175100300015 neutrons, normalized to 1., before reconstruction by 4175100300016 regularization method. 4175100300017 CORRECTION For background - 5 neutrons. 4175100300018 For 244Fm spontaneous fission - 2 events. 4175100300019 STATUS (TABLE) Table 1 of J,EPJ/A,58,108,2022 4175100300020 ENDBIB 18 0 4175100300021 NOCOMMON 0 0 4175100300022 DATA 5 10 4175100300023 PART-OUT DATA DATA-ERR MISC MISC-ERR 4175100300024 NO-DIM NO-DIM NO-DIM NO-DIM NO-DIM 4175100300025 0. 0. 0.021 0.077 0.018 4175100300026 1. 0.070 0.028 0.277 0.034 4175100300027 2. 0.184 0.033 0.332 0.027 4175100300028 3. 0.220 0.032 0.170 0.016 4175100300029 4. 0.192 0.031 0.102 0.010 4175100300030 5. 0.154 0.030 0.038 0.006 4175100300031 6. 0.113 0.027 0.004 0.002 4175100300032 7. 0.061 0.027 0. 0.002 4175100300033 8. 0.006 0.018 4175100300034 9. 0. 0.016 4175100300035 ENDDATA 12 0 4175100300036 ENDSUBENT 35 0 4175100399999 SUBENT 41751004 20220720 42074175100400001 BIB 5 9 4175100400002 REACTION (96-CM-248(0,F),PR,NU) 4175100400003 SAMPLE No information 4175100400004 REL-REF (A,,N.E.Holden+,J,RE,96,289,1986) 4175100400005 3.13+-0.03 n/fis with variance 1.29 4175100400006 (A,41425006,A.S.Vorobyev+,C,2004SANTA,1,613,2004) 4175100400007 =S,AIP-769,1,613,2005. 4175100400008 3.13+-0.02 n/fis with variance 1.37 4175100400009 MISC-COL (MISC) Variance of multiplicity distribution SIG2. 4175100400010 STATUS (TABLE) Table 2 of J,EPJ/A,58,108,2022 4175100400011 ENDBIB 9 0 4175100400012 NOCOMMON 0 0 4175100400013 DATA 3 1 4175100400014 DATA DATA-ERR MISC 4175100400015 PRT/FIS PRT/FIS NO-DIM 4175100400016 3.13 0.01 1.35 4175100400017 ENDDATA 3 0 4175100400018 ENDSUBENT 17 0 4175100499999 ENDENTRY 4 0 4175199999999