ResultsinNeutrinoOscillationsfromSuper-KamiokandeI.ppt

1、物理学,金信弘(筑波大学物理学系)2003年9月25日Soo-Bong Kim氏(SNU)講演引用,d ?,2002年度物理学賞for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos“ Raymond Davis Jr. USA (University of Pennsylvania) Masatoshi Koshiba Japan (University of Tokyo) for pioneering contributions to astrophy

2、sics, which have led to the discovery of cosmic X-ray sources“ Riccardo Giacconi USA (Associated Universities Inc.),天文学,Neutrinos can probe the interior of stars（星内部）. Neutrinos are transparent to the Milky way（銀河通過）. Neutrinos are efficient to carry out energies from the star explosion（星爆発）. Neutri

3、nos from Sun, Supernova explosion, Galaxy, Dark-Matter Annihilation, etc（太陽，超新星爆発，銀河，暗黒物質消滅）.,宇宙線,Solar Neutrinos太陽 Atmospheric Neutrinos大気 Supernova Neutrinos超新星 Cosmic Background Neutrinos宇宙背景 Ultra High Energy Neutrinos超高,W. Pauli (1931): Undetectable neutral particle E. Fermi (1934): “Neutrino”

4、F. Reines (1956): Discovery Nobel Prize (1995) L. Lederman, M. Schwartz, J. Steinberg (1962): Muon Neutrino Nobel Prize (1988),R. Davis (1968): First detection of solar neutrinosNobel Prize (2002) M. Koshiba (1987): Supernova neutrinos by Kamiokande-II and IMBNobel Prize (2002) Y. Totsuka (1998): Os

5、cillation of atmospheric neutrinos at Super-Kamiokande SNO (2002): Oscillation of solar neutrinos,物理学歴史,素粒子？,原子,原子核,陽子,電子,（）内数字GeV単位書質量,物質構成粒子（）,力伝粒子（）,(0.002)(1.3)(175 )(0.005)(0.14) ( 4.2),電子(0.0005) 粒子(0.106)(1.8)電子 e ,電荷2/3 - 1/3 - 1 0,(0)光子(0)粒子(80) 粒子(91),強力,電磁気力,弱力,素粒子素粒子間力（素粒子物理標準理論）,GUT（大統一

6、理論）規模物理検証 (質量振動) 宇宙膨張 (暗黒物質) 混合 (MNS 行列) 天文学 (超高, 超新星, ),用素粒子物理学宇宙物理学,振動,2種類場合,P(nanb) = sin22q sin2(1.27Dm2L/E),Dm2 = m22 - m12 (eV2)L (km): Distance from source to detectorE (GeV): Neutrino energy,振動実験結果,Solar neutrino data 太陽 (Super-Kamiokande, SNO) Atmospheric neutrino data 大気 (Super-Kamiokande)

7、 Neutrino beam data (K2K),Super- Kamiokande（）,Water Cherenkovdetector,1000 m underground 50,000 ton (22,500 ton fid.) 11,146 20 inch PMTs 1,885 anti-counter PMTs,SK-I: Apr 1996 Jul 2001 SK-II: Dec 2002 ,SK-1(Jan. 1996),2001年11月12日事故,6777 ID + 1100 OD PMTs destroyed,Never repeat the accident,Encase a

8、ll the existing PMTs (5246) in acrylic + frp cases to prevent shock wave generation,事故繰返為,修理完了 (Sep. 17, 2002)SK-II Resumed data-taking in Dec, 2002!,Solar Neutrino Data of Super-Kamiokande,COSqsun,Ee = 5.0 - 20 MeV,ne e g nee scattering (contains 15% of NC),22385 solar n events(14.5 events/day),Fro

9、m K.Inoue (Tohoku Univ.),KamLAND（）(Confirmation of solar neutrino oscillations),太陽,See also: Phys. Lett. B539 179-187, 2002,Solar neutrino oscillations (ne g nm/nt) are established by Super-Kamiokande and SNO data. (Dm122 10-4eV2 ) LMA solutions are favored by no spectrum distortion and no day/night

10、 effect. Large Mixing Angle(LMA) by a global fit:2.5 x10-5eV2 Dm2 (Dm122) 3.3 x10-4eV20.25 tan2q 0.92 (90%CL),3-flavor mixing間混合 q13?,太陽大気間混合,nm,nt,ne,Atmospheric nDm232=3x10-3 eV2,Solar nDm12210-4 eV2,Oscillation Probabilities when,q13:ne appearance,q23 :nm disappearance,common,q12:ne disappearance

11、,Atmospheric n,Solar n,3間振動,3間振動実験結果許領域,consistent with CHOOZs excluded region,(Dm2 = Dm232 Dm132),大気,nm n n t 2 flavor oscillations are established. (Dm2 = Dm232 Dm132 Dm122 ) Dm2 = (1.63.9)x10-3eV 2 sin22q23 0.92 (90% C.L.) ns admixture is disfavored (sin2 x0.19 90%CL). 3 flavor oscillations are t

12、ested and give an allowed region of q13, consistent with CHOOZ: sin2q13 0.1 (90% C.L.),K2K (KEK to Kamioka)実験,KEK検出 (June 1999 July 2001),Super-K 事象検出,Tspill,TSK,GPS,TSpill: Abs. time of spill startTSK: Abs. time of SK eventTOF: 0.83ms (KEK to Kamioka),No Decay-e,HE Trig.,FC: fully contained (No act

13、ivity in Outer Detector) FV: 22.5kt Fiducial Volume,Expected Atm. n BG 10-3 within 1.5ms.,1.5ms,500msec,5msec,DT (msec),DT (msec),FCFV,56 events !,Super-Kamiokande反応,Best fit point (sin22q , Dm2)method 1KS test prob.(shape)= 79%NSK prediction =54 (obs 56)method 2 KS-testNSK82%shape 93%NSK+shape50%,#

14、Events,Protons on target (E18),Number of total interactions (Jun99-Jul01 ),Reconstructed En shape of 1-RFCm (29 1-R events in Nov99-Jul01),Nobs=56 Nexp=80.1,+6.2-5.4,+,w/ oscillations(KS-test = 79%),K2K実験振動結果,Null oscillation probability e 1%,Method1 0.7%Method2 0.4%,Method1 2.8x10-3Method2 2.7x10-3,Super-K result,Two independent methods agree with each other,K2K実験結果,MNS(Maki-Nakagawa-Sakata) 混合行列,混合(素粒子物理新分野始!),JHF-神岡実験(2007),