ENTRY 14659 20200829 14721465900000001 SUBENT 14659001 20200829 14721465900100001 BIB 11 68 1465900100002 TITLE Measurement of neutron-proton capture in the SNO+ 1465900100003 water phase 1465900100004 AUTHOR (M.R.Anderson,S.Andringa,M.Askins,D.J.Auty,N.Barros, 1465900100005 F.Barao,R.Bayes,E.W.Beier,A.Bialek,S.D.Biller, 1465900100006 E.Blucher,R.Bonventre,M.Boulay,E.Caden,E.J.Callaghan, 1465900100007 J.Caravaca,D.Chauhan, M.Chen,O.Chkvorets,B.Cleveland, 1465900100008 M.A.Cox,M.M.Depatie,J.Dittmer,F.Di Lodovico,A.D.Earle, 1465900100009 E.Falk,N.Fatemighomi,V.Fischer,E.Fletcher,R.Ford, 1465900100010 K.Frankiewicz,K.Gilje,D.Gooding,C.Grant,J.Grove, 1465900100011 A.L.Hallin,D.Hallman,S.Hans,J.Hartnell,P.Harvey, 1465900100012 W.J.Heintzelman,R.L.Helmer,D.Horne,B.Hreljac,J.Hu, 1465900100013 A.S.M.Hussain,A.S.Inacio,C.J.Jillings,T.Kaptanoglu, 1465900100014 P.Khaghani,J.R.Klein,R.Knapik,L.L.Kormos,B.Krar, 1465900100015 C.Kraus,C.B.Krauss,T.Kroupova,I.Lam,B.J.Land,A.LaTorre,1465900100016 I.Lawson,L.Lebanowski,E.J.Leming,A.Li,J.Lidgard, 1465900100017 B.Liggins,Y.H.Lin,Y.Liu,V.Lozza,M.Luo,S.Maguire,A.Maio,1465900100018 S.Manecki,J.Maneira,R.D.Martin,E.Marzec,A.Mastbaum, 1465900100019 N.McCauley,A.B.McDonald,P.Mekarski,M.Meyer,C.Mills, 1465900100020 I.Morton-Blake,S.Nae,M.Nirkko,L.J.Nolan,H.M.O'Keeffe, 1465900100021 G.D.Orebi Gann,M.J.Parnell,J.Paton,S.J.M.Peeters, 1465900100022 S.J.M.Peeters,T.Pershing,L.Pickard,G.Prior,A.Reichold, 1465900100023 S.Riccetto,R.Richardson,M.Rigan,J.Rose,R.Rosero, 1465900100024 P.M.Rost,J.Rumleskie,I.Semenec,F.Shaker,M.K.Sharma, 1465900100025 K.Singh,P.Skensved,M.Smiley,M.I.Stringer,R.Svoboda, 1465900100026 B.Tam,L.Tian,J.Tseng,E.Turner,R.Van Berg,J.G.C.Veinot, 1465900100027 C.J.Virtue,E.Vazquez-Jauregui,S.C.Walton,J.Wang,M.Ward,1465900100028 J.J.Weigand,J.R.Wilson,P.Woosaree,A.Wright,J.P.Yanez, 1465900100029 M.Yeh,T.Zhang,Y.Zhang,K.Zuber,A.Zummo) 1465900100030 The SNO+ collaboration 1465900100031 INSTITUTE (1CANQU,1USAUCX,1USABRK,1CANALA,2PRTLIS,1USAPEN, 1465900100032 2UK OXF,1USACHI,2UK LVP,2GERDRE,2UK KCL,2UK SSX, 1465900100033 1USADAV,1USABST,1USABNL,1CANTMF,2UK QML,3MEXIFM, 1465900100034 3HUNDEB) 1465900100035 (2PRTPRT) Laboratory of Instrumentation and 1465900100036 Experimental Particle Physics,Lisbon 1465900100037 (1CANCAN)Laurentian University,Sudbury,Ontario 1465900100038 (1CANCAN) SNOLAB, Creighton Mine,Sudbury,Ontario 1465900100039 (1USAUSA) Norwich University,Northfield,Vermont 1465900100040 REFERENCE (J,PR/C,102,014002,2020) 1465900100041 FACILITY SNO+ is a multipurpose neutrino spectrometer located 1465900100042 at SNOLAB, Sudbury, Ontario, Canada 1465900100043 SAMPLE Pure water target was a part of active Cherenkov 1465900100044 detector volume 1465900100045 DETECTOR (CEREN) Pure water target was contained within a 5-cm- 1465900100046 thick acrylic vessel with a radius of 6.0 m, which is 1465900100047 submerged in water. Surrounding the vessel, a 1465900100048 geodesic structure with a radius of 8.9 m supports 1465900100049 more than 9300 Hamamatsu R1408 photomultiplier tubes 1465900100050 that face inward. Cherenkov light produced by 4.4 MeV 1465900100051 gammas (emmited in approx. 60% of neutron producing 1465900100052 reactions alpha+9Be -> 12C +n ) and 2.2 MeV produced 1465900100053 in p+n -> 2H were used in analysis. Trigger for the 1465900100054 event analysis was set to coincident pulses from 1465900100055 7 PMTs. Detector is located at SNOLAB, Creighton Mine, 1465900100056 Sudbury, 2.0 km underground. 1465900100057 METHOD (COINC) Delayed coincidence between 4.4 MeV and 2.2 1465900100058 MeV gamma rays was analysed 1465900100059 INC-SOURCE (AM-BE) Am-Be source used in experiment had a rate of 1465900100060 (67.4+-0.7) n/s. Source was doubly encapsulated in a 1465900100061 stainless steel cylinder of 0.8 cm diameter and 1.0 1465900100062 cm height and further shielded with black Delrin 1465900100063 thermoplastic encapsulation. Fully encapsulated 1465900100064 source was a cylinder of approximately 6 cm in 1465900100065 diameter and 8 cm in height. 1465900100066 ANALYSIS Neutron capture time constant was measured and 1465900100067 converted to thermal neutron proton capture cross 1465900100068 section 1465900100069 HISTORY (20200829C) Compiled by S.H. 1465900100070 ENDBIB 68 0 1465900100071 NOCOMMON 0 0 1465900100072 ENDSUBENT 71 0 1465900199999 SUBENT 14659002 20200829 14721465900200001 BIB 3 4 1465900200002 REACTION (1-H-1(N,G)1-H-2,,SIG) 1465900200003 ERR-ANALYS (ERR-SYS) Systematic uncertainty from temperature 1465900200004 variation and the impact of neutron energy spectrum 1465900200005 STATUS (TABLE) Data taken from p. 7 of the reference 1465900200006 ENDBIB 4 0 1465900200007 NOCOMMON 0 0 1465900200008 DATA 4 1 1465900200009 EN DATA +ERR-SYS -ERR-SYS 1465900200010 EV MB MB MB 1465900200011 0.0253 336.3 1.2 1.5 1465900200012 ENDDATA 3 0 1465900200013 ENDSUBENT 12 0 1465900299999 ENDENTRY 2 0 1465999999999