ENTRY 32915 20241015 3291500000001 SUBENT 32915001 20241015 20250110 3291500100001 BIB 15 42 3291500100002 TITLE Measurement of neutron-induced fission cross sections 3291500100003 of 235U and 238U relative to n-p scattering at CSNS 3291500100004 Back-n facility 3291500100005 AUTHOR (Yonghao Chen,Yiwei Yang,Zhizhou Ren,Wei Jiang, 3291500100006 Ruirui Fan,Han Yi,Rong Liu,Jingyu Tang,Hantao Jing, 3291500100007 Yang Li,Qiang Li,Zhixin Tan) 3291500100008 INSTITUTE (3CPRIHP,3CPRNPC,3CPRHST) 3291500100009 REFERENCE (J,EPJ/CS,284,01013,2023) preliminary results 3291500100010 #doi:10.1051/epjconf/202328401013 3291500100011 FACILITY (SYNCH,3CPRIHP) Back-n white neutron source of China 3291500100012 Spallation Neutron Source (CSNS) 3291500100013 INC-SOURCE (SPALL) Spallation neutrons are generated by 3291500100014 bombarding 1.6 GeV protons to a thick tungsten target 3291500100015 with a 25-Hz repetition frequency. 3291500100016 DETECTOR (FISCH) A fission ionization chamber for the cross- 3291500100017 section measurement (FIXM) was upstream placed. 3291500100018 (TELES) Proton recoil telescopes (PRTs) were 3291500100019 downstream installed in a chamber after FIXM for 3291500100020 measuring the n-p scattering. The chamber was 3291500100021 maintained at 5E-3 Pa during the measurement. 3291500100022 SAMPLE Two 235U and two 238U samples were mounted in the 3291500100023 chamber. All the samples inside FIXM are circular in 3291500100024 diameters of 50 mm with masses of a few milligrams. 3291500100025 METHOD (TOF) The detectors were installed at Back-n end 3291500100026 station 1, which was about 57 meters away from the 3291500100027 spallation target. 3291500100028 MONITOR (1-H-1(N,EL)1-H-1,,SIG) 3291500100029 MONIT-REF (,A.D.Carlson+,J,NDS,148,143,2018) 3291500100030 The n-p scattering cross sections are taken from 3291500100031 IAEA standards below 20 MeV. 3291500100032 (,,3,JEFF-3.1.2,,2012) The n-p scattering cross 3291500100033 sections are taken from JEFF-3.1.2 above 20 MeV. 3291500100034 ANALYSIS A shape measurement was done, and the 235, 238U(n,f) 3291500100035 cross sections were normalized to the IAEA standards 3291500100036 at 14.5 MeV. 3291500100037 ERR-ANALYS (ERR-S) The statistical errors of this work are 3291500100038 ranging from less than 1% up to 6%. 3291500100039 STATUS (PRELM) 3291500100040 (TABLE,,Yonghao Chen+,J,EPJ/CS,284,01013,2023) 3291500100041 Data presented by author 3291500100042 HISTORY (20240930R) The data received from Yonghao Chen 3291500100043 (20241015C) Yang Su (CNDC) 3291500100044 ENDBIB 42 0 3291500100045 NOCOMMON 0 0 3291500100046 ENDSUBENT 45 0 3291500199999 SUBENT 32915002 20241015 20250110 3291500200001 BIB 2 2 3291500200002 REACTION (92-U-235(N,F),,SIG) 3291500200003 MONITOR ((MONIT)92-U-235(N,F),,SIG) 3291500200004 ENDBIB 2 0 3291500200005 COMMON 2 3 3291500200006 EN-NRM MONIT 3291500200007 MEV B 3291500200008 14.5 2.090 3291500200009 ENDCOMMON 3 0 3291500200010 DATA 4 23 3291500200011 EN EN-RSL DATA ERR-S 3291500200012 MEV MEV B B 3291500200013 10.5000 0.5000 1.7530 0.0118 3291500200014 11.5000 0.5000 1.7017 0.0129 3291500200015 12.5000 0.5000 1.7926 0.0153 3291500200016 13.5000 0.5000 1.9674 0.0184 3291500200017 14.5000 0.5000 2.0900 0.0214 3291500200018 15.5000 0.5000 2.0492 0.0224 3291500200019 16.5000 0.5000 2.1858 0.0269 3291500200020 17.5000 0.5000 2.1672 0.0290 3291500200021 18.5000 0.5000 2.1135 0.0307 3291500200022 19.5000 0.5000 2.1689 0.0343 3291500200023 21.9008 1.0079 2.0705 0.0262 3291500200024 24.0138 1.1051 2.0661 0.0291 3291500200025 26.3306 1.2117 2.1405 0.0353 3291500200026 28.8709 1.3286 2.1736 0.0387 3291500200027 31.6563 1.4568 2.1997 0.0449 3291500200028 34.7105 1.5973 1.9858 0.0439 3291500200029 38.0593 1.7515 1.9351 0.0488 3291500200030 41.7312 1.9204 2.0203 0.0606 3291500200031 45.7573 2.1057 1.9618 0.0691 3291500200032 50.1719 2.3089 1.8987 0.0751 3291500200033 55.0124 2.5316 1.8798 0.0886 3291500200034 60.3199 2.7759 1.8634 0.1027 3291500200035 66.1394 3.0437 1.8274 0.1081 3291500200036 ENDDATA 25 0 3291500200037 ENDSUBENT 36 0 3291500299999 SUBENT 32915003 20241016 20250110 3291500300001 BIB 2 2 3291500300002 REACTION (92-U-238(N,F),,SIG) 3291500300003 MONITOR ((MONIT)92-U-238(N,F),,SIG) 3291500300004 ENDBIB 2 0 3291500300005 COMMON 2 3 3291500300006 EN-NRM MONIT 3291500300007 MEV B 3291500300008 14.5 1.190 3291500300009 ENDCOMMON 3 0 3291500300010 DATA 4 23 3291500300011 EN EN-RSL DATA ERR-S 3291500300012 MEV MEV B B 3291500300013 10.5000 0.5000 1.0278 0.0079 3291500300014 11.5000 0.5000 1.0109 0.0086 3291500300015 12.5000 0.5000 1.0073 0.0097 3291500300016 13.5000 0.5000 1.0872 0.0114 3291500300017 14.5000 0.5000 1.1900 0.0134 3291500300018 15.5000 0.5000 1.2030 0.0143 3291500300019 16.5000 0.5000 1.3254 0.0176 3291500300020 17.5000 0.5000 1.3601 0.0194 3291500300021 18.5000 0.5000 1.4034 0.0215 3291500300022 19.5000 0.5000 1.4675 0.0243 3291500300023 21.9008 1.0079 1.5215 0.0199 3291500300024 24.0138 1.1051 1.5156 0.0220 3291500300025 26.3306 1.2117 1.5776 0.0266 3291500300026 28.8709 1.3286 1.6665 0.0302 3291500300027 31.6563 1.4568 1.7623 0.0365 3291500300028 34.7105 1.5973 1.5995 0.0357 3291500300029 38.0593 1.7515 1.5892 0.0404 3291500300030 41.7312 1.9204 1.6928 0.0510 3291500300031 45.7573 2.1057 1.6666 0.0589 3291500300032 50.1719 2.3089 1.6416 0.0651 3291500300033 55.0124 2.5316 1.6169 0.0764 3291500300034 60.3199 2.7759 1.6250 0.0897 3291500300035 66.1394 3.0437 1.5997 0.0948 3291500300036 ENDDATA 25 0 3291500300037 ENDSUBENT 36 0 3291500399999 ENDENTRY 3 0 3291599999999