Super-Kamiokande – Neutrinos from MeV to TeV Mark Vagins University of California, Irvine EPS/HEP Lisbon July 22, 2005

The Collaboration 1 Kamioka Observatory, ICRR, Univ. of Tokyo, Japan 2 RCCN, ICRR, Univ. of Tokyo, Japan 3 Boston University, USA 4 Brookhaven National Laboratory, USA 5 University of California, Irvine, USA 6 California State University, Dominguez Hills, USA 7 Chonnam National University, Korea 8 Duke University, USA 9 George Mason University, USA 10 Gifu University, Japan 11 University of Hawaii, USA 12 Indiana University, USA 13 KEK, Japan 14 Kobe University, Japan 15 Kyoto University, Japan 16 Los Alamos National Laboratory, USA 17 Louisiana State University, USA 18 University of Maryland, College Park, USA 19 University of Minnesota, Duluth, USA 20 Miyagi University of Education, Japan 21 SUNY, Stony Brook, USA 22 Nagoya University, Japan 23 Niigata University, Japan 24 Osaka University, Japan 25 Seoul National University, Korea 26 Shizuoka Seika College, Japan 27 Shizuoka University, Japan 28 Sungkyunkwan University, Korea 29 RCNS, Tohoku University, Japan 30 University of Tokyo, Japan 31 Tokai University, Japan 32 Tokyo Institute for Technology, Japan 33 Warsaw University, Poland 34 University of Washington, USA ~140 collaborators 34 institutions 4 countries (as of Jan. 2005) +Tsinghua Univ., China (June, 2005~)

Super- Kamiokande The Location

The Detector tons ultra-pure water 1 km overburden = 2700 m.w.e tons fiducial volume

SK-I: 40% PMT Coverage SK-II: 19% PMT Coverage April 1996  July 2001 December 2002  September 2005

The Neutrino Sources Solar (Low E) Atmospheric (High E) 5 MeV  20 MeV 100 MeV  10 TeV+ P  = 1 – sin 2 2  sin 2 (1.27 ) m2Lm2L E

8 B ’s hep ’s SK-I: 5 MeV SK-II: 7 MeV SK-III: 4 MeV

12 MeV solar Result of -e elastic scattering: points back in solar direction

603 MeV atmospheric muon Note sharp edge of ring from muon produced by  -nucleon interaction

492 MeV atmospheric electron Note diffuse edge of ring from electron produced by e -nucleon interaction

Tau candidate event (~3 GeV) (Still Fully Contained)

Upward-Going Muons

Upward-going atmospheric  induced muon Note activity in outer detector: not contained Parent energy between 2 GeV and 40 TeV!

Atmospheric Results

No Oscillation (sin 2 2  23 =1.0,  m 2 23 =2.5X10 -3 eV 2 ) 1489 days of data

No Oscillation (sin 2 2  23 =0.98,  m 2 23 =3.1X10 -3 eV 2 ) 627 days of data

Solar Results

SK-I: 8 B Solar Neutrino Flux 8 B flux = 2.35  0.02  0.08 [x10 6 /cm 2 /s] Data / SSM BP2004 =  0.004(stat.) (syst.)  230 solar  events PLB539 (2002) 179 Electron total energy: MeV May 31, 1996 – July 15, 2001 (1496 days ) Data / SSM BP2000 =  0.005(stat.) (syst.)

SK-II: 8 B Solar Neutrino Flux SK-I 8 B flux = 2.35  0.02  0.08 [x10 6 /cm 2 /s]

Seasonal Variation: SK-I + SK-II

SK-I Day / Night Variation A DN = (Day-Night) (Day+Night)/2

SK-II Day / Night asymmetry = /-0.049(stat.) (sys.) A DN = (Day-Night) (Day+Night)/2 SK-I D/N Asymmetry: / Preliminary

SK-I: Energy Spectrum Energy correlated systematic error No strong distortion seen

SK-II: Energy Spectrum

Oscillation parameters from solar neutrino and KamLAND experiments (SK-I data only) Solar 95% 99.73% KamLAND Solar+KamLAND 12

Ongoing Work: ATM MaVaN Analysis for SK-I/II ATM L/E Analysis for SK-II Solar SK-II Oscillation Analysis Three Flavor Analyses Improved Relic Supernova Neutrino Analysis Tau Appearance Paper (soon!) Full SK-I Solar Paper (very soon!) Gadolinium Enrichment Studies for SK-III Many others… Next Up: Drain Super-Kamiokande-II and Restore 40% PMT Coverage Resume Data-Taking with SK-III by June 2006 Beacom & Vagins, PRL93 (2004)171101

L/E Analysis

L/E Analysis Motivation E Path length L Neutrino energy  Use only high resolution L/E events A first dip can be observed P  = (cos 2  sin 2  x exp(– )) 2 m 22 Neutrino oscillation : P  = 1 – sin 2 2  sin 2 (1.27 ) m2Lm2L E Neutrino decoherence : P  = 1 – sin 2 2  x (1 – exp(–   )) 2 1 Neutrino decay : L E L E

L/E Distribution Null oscillation MC Best-ft expectation days FC+PC First dip is seen as expected by neutrino oscillation Best fit expectation w/ systematic errors

Test for neutrino decay & neutrino decoherence Oscillation Decay Decoherence  2 min =37.9/40 d.o.f  2 min =49.1/40 d.o.f   2 =11.3  2 min =52.4/40 d.o.f   2 =14.5  2 =11.4 for decay  3.4   2 =14.6 for decoherence  3.8  The first dip the data cannot be explained by other models

Comparison of the allowed parameter regions between zenith angle analysis and L/E analysis L/E analysis Zenith angle analysis K2K Soudan 2 MACRO 90% allowed regions

Mass Varying Neutrinos (MaVaN)

Tau Appearance

Result: a = 1.82 ±.61 b = 0.96 Expected #: 35.2 fitted #: 64 ± 21 Signal Eff: 44%  Total number of tau = 145 (total exp’d =79) Partially Polarized Distribution Likelihood Analysis

GADZOOKS!

Here’s what the coincident signals in Super-K with GdCl 3 will look like (energy resolution is applied):

Oh, and as long as we’re collecting e ’s… GADZOOKS! GADZOOKS! will collect this much reactor neutrino data in two weeks. KamLAND’s first 22 months of data Hyper-K with GdCl 3 will collect six KamLAND years of data in one day!

This summer I’ll employ some excellent large-scale hardware to find out if the GdCl 3 technique will work: K2K’s 1 kiloton tank will be used for “real world” studies of Gd Water Filtering – UCI built and maintains this water system Gd Light Attenuation – using real 20” PMTs Gd Materials Effects – many similar detector elements as in Super-K We are nearly ready for this effort…