Results in Neutrino Physics & Astrophysics : Highlights Overview Highlights in Neutrino Oscillation Results from Atmospheric, Solar, Accelerator and Reactor Neutrino Experiments Future Directions & Projects Outlook Henry T. Wong / 王子敬 Academia Sinica / 中央研究院 @

Neutrino Physics Road-Map Grand Unified Theories (GUT) L(n-mass)0 Structures & Compositions of Universe mn’s;Uij’s 0 n-Oscil. mn’s n-decays 0nbb b-spect.dist. anomal. int. ………. Particle Physics Cosmology Nuclear Physics Astrophysics n’s as Probe

Neutrino Sources n‘s everywhere: 300 per c.c. Observed window n‘s everywhere: 300 per c.c. from sun, supernovae, cosmic rays, reactors, accelerators, astrophysical sources, & relic Big Bang …

Cross Sections Challenges of Neutrino Experiments : Strong Electro-magnetic Weak  l(H2O)  250 light years ! Challenges of Neutrino Experiments : “How to Beat the Small Cross-Section?” i.e. By building Massive Detectors  while keeping cost/background Low !

at least as much neutrinos by mass as visible matter !

Solar Neutrinos

Super-Kamionkande ※ Water Cerenkov detector: 50k tons, viewed by 11,000+ =50 cm PMTs in 1000 m underground site in central Japan ※ Physics: solar n, atmospheric n , long baseline accelerator n, proton decays .. ※ Accidents (PMTs imploded) Nov 01, 50% PMT data again end of 02 !! No major deterioration in data quality

The Sun IS Burning !! Measurement of Eccentricity of Earth’s Orbit !!!

Sudbury Neutrino Observatory (SNO) ※ 1 kton Heavy Water Cerenkov detector: shielded by 7k ton of water viewed by 9456 PMTs located 2000 m underground in Canada. ※ Physics: Solar n …

Solution of the “Solar Neutrino Problem” Standard Solar Model + Standard Particle Physics Model Solution of the “Solar Neutrino Problem”

Atmospheric Neutrinos Up-Down Asymmetry & Deficit nm disappearing, ne OK, Strong evidence : > 15s Better fits for nt appearing Up-Down Asymmetry & Deficit

KEK-SuperK (K2K) Accelerator n Flight path 250 km Deficit of nm at far detector  spectral distortion

KamLAND Long Baseline Reactor n ave. flight path of 160 km  (sensitive to 20% of world’s reactors !) ave. flight path of 160 km 1 kton liquid scintillator in old Kamiokande site probe “LMA” for solar n historical results only 5 years from approved !!!!

A “By-Product” : Earth’s Radiogenic Power : Thermal measurements : 42 TW Geophysical Model : 16 TW KamLAND measurement : < 60 TW

Neutrino Oscillations (in 2-family language) Neutrinos produced & detected as ne, nm , nt (“flavor eigenstates”) Propagate as n1 , n2 (“mass eigenstates”) Probability of producingνe & detecting as νe :  Matter Effect : Origin – ne+e (CC+NC) Vs nm +e(NC) 3 families at resonance

Dm2 –  : Summary 2002 PDG 2000: SK atm. n SNO solar n

2004 K2K : Consistent Checks to atm. n SK

+ observations of L/E oscillation signatures from SK atm-n & KamLAND (averaged)…..

Three Families of Neutrino Mixing The Maki-Nakagawa-Sakata (MNS) matrix : Q13 : crucial unknown towards CP-studies Possible CP Violation in n Sector:

Normal Hierarchy: Dm232>0 Inverted Hierarchy: Dm232<0 Neutrino Mass Structures : Normal Vs Inverted Hierarchy ?? Quasi-Degenerate Vs Hierarchical ?? Dirac Vs Majorana ?? Dm2atm Dm2 Dm2 Normal Hierarchy: Dm232>0 Inverted Hierarchy: Dm232<0 0 = ?

Deeper Physical Questions ……….. In particular : Is q12+qCabbibo = p/4 ? Is q23=p/4 ? Is q13 = 0 ? …….. Mixing angles may reveal deeper/higher energy scale & symmetry principles

neutrino mass structures may reveal GUTs scale physics (e. g neutrino mass structures may reveal GUTs scale physics (e.g. See-Saw Mechanisms) :

Future Experimental Projects Long baseline accelerator/reactor experiments (NuMI, CNGS, T2K, q13 ……) ※Detailed studies of mixing matrices by oscillation studies 0nbb experiments ※ Distinguish mass hierarchy, fix absolute mass scales Direct mass searches in b-decay ※ Probe degenerate mass structures Neutrino properties (e.g. magnetic moments studies…) ※ How neutrino interacts/couples with outside world Neutrino from sky and earth ※ do astronomy/earth science with neutrino sources, understand roles of neutrinos in astrophysics/geophysics

Long Baseline Accelerator Neutrino Projects : 730 km NuMI  MINOS CNGS  Icarus/OPERA

0nbb Candidate Isotopes

Neutrino Mass Measurements 0nbb decay: b decay kinematics: microcalorimeters MAC-E spectrometers cosmology & structure formation astrophysics: SN ToF measurements 3H NEMO3 76Ge @ LNGS ´90-´03 (71.7 kg×y) |mee|=0.44+0.13-0.2 eV D.N. Spergel et al: Smn < 0.69 eV (95%CL) S.W. Allen et al: Smn = 0.56 eV (best fit) SuperK, SNO, OMNIS + grav.waves: potential for ~1eV sensitivity? 187Re 2nbb

IceCube High Energy Neutrino Telescope e.g. Volume ~km3 !!

TEXONO Research Program in Taiwan KS NPS-II : 2 cores  2.9 GW KS n Lab: 28 m from core#1

Reactor Neutrino Interaction Cross-Sections On-Going Data Taking: SM s(ne) T > 2 MeV R&D : Coh. (nN) T < 1 keV Results & More Data: mn(ne) T ~ 1-100 keV

min. 700 m of rock overburden TEXONO  KIMS @ Y2L Install 5 g ULB-ULEGe at Y2L on January 2005 Study background and feasibility for CDM searches may evolve into a full-scale (1 kg) CDM experiment Yangyang (襄陽) Lab (Y2L) min. 700 m of rock overburden

Sensitivity Plot for CDM-WIMP search with 1 kg ULEGe at 100 eV threshold ………

Summary & Outlook Neutrinos are important but strange objects history of n physics full of surprises ! Strong evidenceS of massive n’s & finite mixings Physics Beyond the Standard Model ! More experiments & projects coming up EVEN MORE EXCITEMENT !