ENTRY 23600 20201015 22952360000000001 SUBENT 23600001 20201015 22952360000100001 BIB 12 37 2360000100002 TITLE Improved accuracy in the determination of the thermal 2360000100003 cross section of 14N(n, p) 14C for neutron lifetime 2360000100004 measurement 2360000100005 AUTHOR (R.Kitahara,K.Hirota,S.Ieki,T.Ino,Y.Iwashita, 2360000100006 M.Kitaguchi,J.Koga,K.Mishima,A.Morishita,N.Nagakura, 2360000100007 H.Oide,H.Otono,Y.Seki,D.Sekiba,T.Shima,H.M.Shimizu, 2360000100008 N.Sumi,H.Sumino,K.Taketani,T.Tomita,T.Yamada, 2360000100009 S.Yamashita,M.Yokohashi,T.Yoshioka) 2360000100010 INSTITUTE (2JPNKTO,2JPNOSA,2JPNNAG,2JPNTOK,2JPNTOH,2JPNKEK, 2360000100011 2JPNKYU,2JPNJAE,2JPNTSU) 2360000100012 (2JPNJPN) J-PARC Center, Tokai, Ibaraki 319-1195, Japan2360000100013 REFERENCE (J,PTEP,2019,093C01,2019) 2360000100014 #doi:10.1093/ptep/ptz096 2360000100015 FACILITY (SYNCH,2JPNKEK) BL05 polarized-beam branch in MLF at 2360000100016 J-PARC 2360000100017 INC-SOURCE (POLNS,SPALL) The pulsed neutron beams are produced 2360000100018 by the spallation process at the MLF in J-PARC. 2360000100019 Neutrons were polarized with a polarization ratio of 2360000100020 94.97% and bunched using the spin-flip chopper. 2360000100021 DETECTOR (MWPC) He and N filled multiwire proportional chamber. 2360000100022 SAMPLE Mixture gas of Isotopic enriched 3He(ratio > 99.5%) 2360000100023 gas, G1 class He gas and nitrogen gas. 2360000100024 Gas-1 3He/14N = 0.0002351(7) 2360000100025 Gas-2 3He/14N = 0.0005212(12) 2360000100026 METHOD (TOF)Events corresponding to the 14N(n,p)14C and 2360000100027 3He(n,p) 3H reactions were identified with deposited 2360000100028 energies. Neutrons were collimated to a beam with a 2360000100029 diameter of 1.5 mm. Flight length = 20 m 2360000100030 ANALYSIS Events corresponding to the 14N(n,p)14C and 3He(n,p) 2360000100031 3H reactions were identified with deposited energies. 2360000100032 The detector efficiency ratio 3He/14N was evaluated. 2360000100033 REL-REF (I,,K.Mishima+,J,NIM/A,600,342,2009) 2360000100034 Details of BL05 of MLF at J-PARC 2360000100035 (I,,Y.Arimoto+,J,NIM/A,799,187,2015) 2360000100036 Details of the Detector 2360000100037 HISTORY (20201015C) Atsushi Kimura 2360000100038 (20201015R) Received from Kenji Mishima 2360000100039 ENDBIB 37 0 2360000100040 NOCOMMON 0 0 2360000100041 ENDSUBENT 40 0 2360000199999 SUBENT 23600002 20201015 22952360000200001 BIB 7 19 2360000200002 REACTION (7-N-14(N,P)6-C-14,,SIG) 2360000200003 STATUS (TABLE) Table 6 in the REFERENCE 2360000200004 SAMPLE Mixture gas of 3He, Nat-He and N2 gas. 2360000200005 Gas-1 3He/14N = 0.0002351(7) 2360000200006 Gas-2 3He/14N = 0.0005212(12) 2360000200007 MONITOR (2-HE-3(N,P)1-H-3,,SIG) 5333(7)b 2360000200008 MONIT-REF ((MONIT),S.F.Mughabghab,B,NEUT.RES,,2-1,2006) 2360000200009 ERR-ANALYS (ERR-S) Statistical uncertainty 2360000200010 (ERR-SYS) Total systematic uncertainty 2360000200011 (ERR-1) Partial systematic unc. due to abundance 2360000200012 ratio of 3He/14N 2360000200013 (ERR-2) Partial systematic unc. due to detector 2360000200014 efficiency 2360000200015 (ERR-3) Partial systematic unc. due to unclassified 2360000200016 events 2360000200017 (MONIT-ERR) Partial systematic unc. due to Monitor 2360000200018 Value 2360000200019 FLAG (1.) Gas-1 3He/14N = 0.0002351(7) 2360000200020 (2.) Gas-2 3He/14N = 0.0005212(12) 2360000200021 ENDBIB 19 0 2360000200022 COMMON 2 3 2360000200023 MONIT MONIT-ERR 2360000200024 B PER-CENT 2360000200025 5333. 0.13 2360000200026 ENDCOMMON 3 0 2360000200027 DATA 8 2 2360000200028 EN DATA ERR-S ERR-SYS ERR-1 ERR-2 2360000200029 ERR-3 FLAG 2360000200030 EV B B B B B 2360000200031 B NO-DIM 2360000200032 0.0253 1.871 0.005 0.006 0.006 0.0012360000200033 0.002 1. 2360000200034 0.0253 1.867 0.003 0.006 0.004 0.0012360000200035 0.002 2. 2360000200036 ENDDATA 8 0 2360000200037 ENDSUBENT 36 0 2360000299999 SUBENT 23600003 20201015 22952360000300001 BIB 6 8 2360000300002 REACTION (7-N-14(N,P)6-C-14,,SIG,,AV) 2360000300003 ANALYSIS Weighted average of the results of Gas-1 and 2 2360000300004 STATUS (TABLE) Table 6 in the REFERENCE 2360000300005 (DEP,23600002) Derived from the results of Gas-1 and 2 2360000300006 MONITOR (2-HE-3(N,P)1-H-3,,SIG) 5333(7)b 2360000300007 MONIT-REF ((MONIT),S.F.Mughabghab,B,NEUT.RES,,2-1,2006) 2360000300008 ERR-ANALYS (ERR-S) Statistical uncertainty 2360000300009 (ERR-SYS) Total systematic uncertainty 2360000300010 ENDBIB 8 0 2360000300011 NOCOMMON 0 0 2360000300012 DATA 4 1 2360000300013 EN DATA ERR-S ERR-SYS 2360000300014 EV B B B 2360000300015 0.0253 1.868 0.003 0.006 2360000300016 ENDDATA 3 0 2360000300017 ENDSUBENT 16 0 2360000399999 SUBENT 23600004 20201015 22952360000400001 BIB 4 7 2360000400002 REACTION ((7-N-14(N,P)6-C-14,,SIG)/(2-HE-3(N,P)1-H-3,,SIG)) 2360000400003 ERR-ANALYS (ERR-S) Statistical uncertainty 2360000400004 (ERR-SYS) Total systematic uncertainty 2360000400005 STATUS (TABLE) Calculated from Fig. 11 in the REFERENCE 2360000400006 The data were presented by Authors. 2360000400007 SAMPLE Mixture gas of 3He, Nat-He and N2 gas. 2360000400008 Gas-1 3He/14N = 0.0002351(7) 2360000400009 ENDBIB 7 0 2360000400010 NOCOMMON 0 0 2360000400011 DATA 4 8 2360000400012 EN DATA ERR-S ERR-SYS 2360000400013 MILLI-EV NO-DIM NO-DIM NO-DIM 2360000400014 1.75 0.0003492 0.0000031 0.0000011 2360000400015 2.13 0.0003526 0.0000028 0.0000012 2360000400016 2.60 0.0003516 0.0000027 0.0000011 2360000400017 3.17 0.0003495 0.0000026 0.0000010 2360000400018 3.87 0.0003527 0.0000027 0.0000012 2360000400019 4.73 0.0003512 0.0000029 0.0000011 2360000400020 5.77 0.0003526 0.0000033 0.0000013 2360000400021 7.04 0.0003455 0.0000036 0.0000011 2360000400022 ENDDATA 10 0 2360000400023 ENDSUBENT 22 0 2360000499999 SUBENT 23600005 20201015 22952360000500001 BIB 4 7 2360000500002 REACTION ((7-N-14(N,P)6-C-14,,SIG)/(2-HE-3(N,P)1-H-3,,SIG)) 2360000500003 ERR-ANALYS (ERR-S) Statistical uncertainty 2360000500004 (ERR-SYS) Total systematic uncertainty 2360000500005 STATUS (TABLE) Calculated from Fig. 11 in the REFERENCE 2360000500006 The data were presented by Authors. 2360000500007 SAMPLE Mixture gas of 3He, Nat-He and N2 gas. 2360000500008 Gas-2 3He/14N = 0.0005212(12) 2360000500009 ENDBIB 7 0 2360000500010 NOCOMMON 0 0 2360000500011 DATA 4 8 2360000500012 EN DATA ERR-S ERR-SYS 2360000500013 MILLI-EV NO-DIM NO-DIM NO-DIM 2360000500014 1.75 0.0003520 0.0000018 0.0000009 2360000500015 2.13 0.0003516 0.0000016 0.0000010 2360000500016 2.60 0.0003511 0.0000015 0.0000009 2360000500017 3.17 0.0003487 0.0000015 0.0000010 2360000500018 3.87 0.0003474 0.0000015 0.0000009 2360000500019 4.73 0.0003511 0.0000017 0.0000009 2360000500020 5.77 0.0003483 0.0000019 0.0000009 2360000500021 7.04 0.0003516 0.0000021 0.0000009 2360000500022 ENDDATA 10 0 2360000500023 ENDSUBENT 22 0 2360000599999 SUBENT 23600006 20201015 22952360000600001 BIB 5 9 2360000600002 REACTION ((7-N-14(N,P)6-C-14,,SIG,,AV)/ 2360000600003 (2-HE-3(N,P)1-H-3,,SIG,,AV)) 2360000600004 ANALYSIS Weighted average of the results of Gas-1 and 2 2360000600005 ERR-ANALYS (ERR-S) Statistical uncertainty 2360000600006 (ERR-SYS) Total systematic uncertainty 2360000600007 STATUS (TABLE) The data were presented by Authors. 2360000600008 (DEP,23600004) Gas-1 3He/14N = 0.0002351(7) 2360000600009 (DEP,23600005) Gas-2 3He/14N = 0.0005212(12) 2360000600010 COMMENT Combined data of Gas-1 2360004 and Gas-2 236005 2360000600011 ENDBIB 9 0 2360000600012 NOCOMMON 0 0 2360000600013 DATA 4 8 2360000600014 EN DATA ERR-S ERR-SYS 2360000600015 MILLI-EV NO-DIM NO-DIM NO-DIM 2360000600016 1.75 0.0003513 0.0000015 0.0000010 2360000600017 2.13 0.0003519 0.0000014 0.0000010 2360000600018 2.60 0.0003512 0.0000013 0.0000010 2360000600019 3.17 0.0003489 0.0000013 0.0000010 2360000600020 3.87 0.0003487 0.0000013 0.0000010 2360000600021 4.73 0.0003511 0.0000015 0.0000009 2360000600022 5.77 0.0003494 0.0000016 0.0000010 2360000600023 7.04 0.0003500 0.0000018 0.0000010 2360000600024 ENDDATA 10 0 2360000600025 ENDSUBENT 24 0 2360000699999 ENDENTRY 6 0 2360099999999