Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Blair Ratcliff Stanford Linear Accelerator Center Physics Results with RICH Counters Outline: Introduction CP Violation in the B Sector The Search for Exotic Baryons Progress in Neutrino Physics Summary 5 th International Workshop on Ring Imaging Cherenkov Counters

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Introduction-I RICH Conference Tradition  Review Physics Impact of RICH Technique A cause for celebration: Use of RICH has become common.  Physics needing high quality PID  Flavor Physics and CP violation studies  Hadron Spectroscopy and the search for exotics  e/separation in Heavy Ion Physics  Physics on a massive scale for cosmic ray and neutrino studies.  Technical Developments  Familiarity: Now a proven technique

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Introduction-II Physics Topic Examples: Exciting Issues (2004) Some Experiments with RICH; Active/ Future: (and without RICH) Heavy Flavor Physics Confronting the Standard Model: Precision Measurements of CP Violation in B Sector; Are there experimental hints of New Physics? BaBar(SLAC), BELLE(KEK), CLEO- III(Cornell), CKM, SELEX, BTeV (Fermilab) LHCb (CERN); Super B- Factory (SLAC/KEK?) Hadron Structure Do Pentaquarks exist? Do other exotic hadrons exist? What is quark content of new states? E.g., D s J [2317]; D s J [2460]; D s J [2632](SELEX); X(3872) Many of the Heavy Flavor Experiments above; HERMES(DESY); COMPASS(CERN); SELEX(Fermilab) Neutrino Physics First Confirmed Physics Beyond SM Are neutrinos Dirac or Majorana? What is the mass hierachy? Neutrino Astrophysics Super Kamiokande; SNO(Sudbury); Lake Baikal; Ice Cube(South Pole); Antares(Mediterranean); NESTOR (Greece)

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Introduction-III Physics Topic Examples: Exciting Issues (2004) Some Experiments with RICH; Active/ Future: (and without RICH) Quark Matter at High Density (Heavy Ions) Discovery of Quark-Gluon Plasma HADES(GSI); PHENIX(RHIC);STAR(RHIC) ALICE (CERN) High Energy Frontier Discovery! Higgs?; Supersymmetry? CDF/D0(Fermilab); LHC/ILC Astro-particle physics Ultra High Energy Cosmic Rays; Very High Energy Gamma Rays; Discussed at this conference; AMS-02(Space); Auger (Argentina); HESS (Namibia); Puebla; TUNKA (Siberia); Mexico/Chalcataya; Magic (la Palma)

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Introduction-IV Apology: Extremely Broad Physics Range…way too many topics to even begin to cover them all. Fortunately…Several physics topics have been addressed here both in review talks and more specific contributed detector/experiment talks.  Astroparticle/Neutrino Physics (Greg Hallewell + the Astroparticle Contributed session)  Heavy Ion Physics (Itzhak Tserruya)  Hadron Spectroscopy (see especially the Contributed talks in the session on “RICH at fixed target experiments” )  Many thanks to the ICEHP04 speakers. Please see their wonderful talks for more details. Special thanks as well to J. Richman, D. MacFarlane, and M. Giorgi Will concentrate on three areas that have had especially exciting results in the last two years….even so only a few specific topics from these areas can be covered:  B Flavor Physics (The Experimental Status of CP Violation)  The search for unusual hadrons and exotics (Do Pentaquarks exist?)  A brief update on Neutrino Physics

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Experimental Status of CPV in the B Sector Tremendous progress since first observation of CPV in 2001 by BaBar and Belle. Sin 2 is only the beginning: CP violation in B decays is not simply a single discovery, but a broad physics program! First precise test of CKM picture. Now looking for small corrections rather than alternatives. The search for new physics Serious attack on all angles and sides of the unitary triangle. New modes of CP violation: Discovery of direct CPV in B decays (2004). Regarding the role of RICH: High quality PID essential both for tagging and final state separation.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Belle Detector SC solenoid 1.5T CsI(Tl) 16X 0 TOF counter 8GeV e - Si vtx. det. 3 lyr. DSSD μ/K L detection 14/15 lyr. RPC+Fe Tracking + dE/dx small cell + He/C 2 H 5 3.5GeV e + Aerogel Cherenkov cnt. n=1.015~1.030 SVD1SVD2 ⇦ 140/fb SVD1 ⇦ + 113/fb SVD2

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Particle Identification at Belle p/K/π separation is based on Likelihood ratio: LR(K)= L(K)+L(π) L(K)

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 DIRC thickness: 8 cm radial incl. supports 19% radiation length at normal incidence DIRC radiators cover: 94% azimuth, 83% c.m. polar angle BaBar Detector Instrumented Flux Return 1.5 T Solenoid DIRC Radiators Drift Chamber Electromagnetic Calorimeter Silicon Vertex Detector e – (9.0 GeV) e + (3.1 GeV) DIRC Standoff Box and Magnetic Shielding

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 N pe and resolution per track (di-muons) vs. polar angle: Fully corrected efficiency/mis-id matrix for a standard selector. Bands represent uncertainties from control samples. Mis-id rates can be tuned down to ~1% over most of momentum space.  (  c, ) = 2.4 mrad Hadronic PID at BaBar

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec /3/99 9/11/001/21/02 6/2/03 10/11/04 Delivered RecordedContinuum B Factory Luminosities-Summer 2004 Total 244(BaBar) + 286(Belle) fb -1 = ab -1 !!

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 CP Violation-A Brief Overview CP violation can be observed by comparing decay rates of particles and antiparticles The difference in decay rates arises from a different interference term for the matter vs. antimatter process. Analogy to double-slit experiment: source Classical double-slit experiment: Relative phase variation due to different path lengths: interference pattern in space B system: extraordinary laboratory for quantum interference experiments: many final states, multiple “paths.”

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Conditions for CP violation   Two amplitudes, A 1 and A 2, with a relative CP- violating phase (  2 ) only   No CP violation: the magnitudes of A and A are the same! Two amplitudes, A 1 and A 2, with both a relative CP-violating phase and CP- conserving phase ( 2 ).Two amplitudes, A 1 and A 2, with both a relative CP-violating phase and CP- conserving phase ( 2 ).  Now have CP violation!

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Type of CP violation Sources of interfering amplitudes Source of CP conserving phase Remarks Direct 2 or more decay amplitudes strong, final-state interactions; value is usually not known Time independent can measure in both neutral (B 0 /B 0 ) and charged (B + /B - ) particle decays. Tagging not required. Mixing : Particle- antiparticle oscillations. First CPV mechanism seen (in Kaon decay) : group of amps with real intermediate states M: group of amps with virtual intermediate states mixing phase: between real and virtual amplitudes Dependence on theory. Very small in B system due to tiny . Time Dependent interference between mixing & decays direct decay after no net mixing and decay after mixing phase in mixing: exactly known! Interference pattern in time due to time- dependence of mixing amplitude. Looking for the perfect way to study CP violation In the SM, the CKM matrix is the only source of CP violating phases.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 CKM and unitarity conditions + phases Unitarity Relations

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 First Observation of Direct CPV in B decays (summer 2004) 4.2 A K =-0.101±0.025±0.005 ± 3.9 Average:A K =-0.114±0.020 (~5.7

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Compilation of other Direct CP searches

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Measuring time-dependent CP asymmetries z Start the clock zz Exclusive B meson and vertex reconstruction Tag vertex reconstruction Flavor Tagging “Typical” Tagging performance (BaBar): Q = 30.5% The asymmetric beam energies of the B-Factories allow the measurement of quantities that depend on decay time. 1ps ~ 170m 1.6 ps ( B ) ~ 250 m

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Calculating the CP Asymmetry General Form

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 The“Golden” modes: the magic of having just one direct decay amplitude If CP violation is due to interference between mixing and one direct decay amp: Pure sin(  m t) time dependence No dependence of asymmetry on hadronic physics For the modes B  J/  K S (J/  K L )

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 sin2  results from charmonium modes bkg Limit on direct CPV B elle B A B AR

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Results on sin2  from ccs, dcc modes

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 sin2β, cos2β and CKM constraints CKM fit to indirect constraints overlaid with sin2β WA measurement cos2β < 0 cos2β > 0 cos2  < 0 ruled out at 87% CL by s- and p-wave interference in angular analysis of B J/  K *0 (K S  0 ) B A B AR

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 A better approach to measuring sin2  ? B   decays Moriond QCD04 Extraction of  similar to , but with advantage of smaller Penguin pollution: B A B AR

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Results for sin2  eff from B   decays BABAR: Updated for ICHEP04 Belle: PRL 93 (2004) B A B AR >3 discrepancy between BABAR & Belle

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Summary of constraints on  Mirror solutions disfavored BABAR & Belle combined

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 The Standard Model Still Reigns! Is there anything beyond? Do and yield the same sin2  ?

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 sin2  and.... and.... New phases from SUSY? In SM interference between B mixing, K mixing and Penguin b  sss or b  sdd gives the same e  as in tree process b  ccs. However loops can also be sensitive to New Physics!

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Results on sin2  from s-penguin modes All new! 2.7  from s-penguin to sin2  (cc) 2.4  from s-penguin to sin2  (cc)

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Averages for sin2  and s-penguin modes 3.6  from s-penguin to sin2  (cc) No sign of Direct CP in averages

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 CPV In B Physics…Summary Tremendous progress by B Factories since first observation of CPV in Competetive experiments have been a strong plus. CP violation in B decays is not simply a single discovery, but a broad physics program with many overlapping experimental results! Precise measurement of Sin 2from charmonium modes. 3.6 discrepancy between charmonium and s-penquin modes. New Physics? Serious attack on all angles and sides of the unitary triangle. Quantitative measurement(2004) of   ) New mode of CP violation: Discovery of direct CPV in B decays (2004). Outlook The increasing data samples from existing B-factories may very well provide convincing evidence for NP by ~2009! YearBBar Pairs Now>5x ~1x x10 9 Unraveling full physics impact probably requires ~ times more luminosity  Motivates New Super-B Factory And Next Generation Hadronic Experiments

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 LHCb Layout Next Generation Experiments at Hadron Machines From 2007 From 2009 Purpose is to collect large samples to over-constrain Unitarity Triangle and search for New Physics.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Next Generation Experiments at B-Factories? Proposed New Super B Factory Machines at KEK/SLAC with L~1-2x10 35 (KEK) ~2010? L~5-7x10 35 (PEP) ~2012?

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Exotic Hadron Spectroscopy-I “Ordinary” Hadrons  (qqq or ) explain most of experimentally observed hadron spectrum. However, QCD  other “non-forbidden” states expected:  Multi-quark states (q ≥ 4); e.g., qqqqq; qqqq  Glueballs (e.g, gg,ggg)  Hybrids (e.g., qqg,qqqg) Long experimental history  some evidence for extra- ordinary states but difficult to interpret:  Light scalar mesons…too many states.  Threshold enhancements…are they resonant?

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Exotic Hadron Spectroscopy-II Recent data have sparked renewed interest:  Pentaquarks ( + (1540);  -- (1862);  c + (3099))  X(3872)  D sJ (2317); D sJ (2460); D sJ (2632)  Threshold enhancements in pp;p Complicated experimental situation:  Varying production channels, energy ranges etc.  Range of detection methods, only some with RICH  Excellent PID is necessary in some cases and powerful in others but is not available in all experiments Look at one topic today  Does the   Pentaquark exist?

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Some Early History  Many searches from late 60’s onwards for s = +1 baryon resonance production (the Z’s)in K + N scattering experiments. Nothing observed.  Summary on s = 1 baryon resonance searches was dropped from PDG as of 1986 with the following comment: “ The general prejudice against baryons not made of three quarks and the lack of any experimental activity in this area make it likely that it will be another 15 years before the issue is decided. ”  PDG’s prediction: the pentaquark issue cannot be settled until  = 2001 So it is past time to find something (or not)!

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 The lowest mass object which they called the Z + (now called  + ) is predicted to be: Exotic: S=+1 Low mass: 1530 MeV Narrow width: ~ 15 MeV J P =1/2 + Pentaquark Revival – The    Prediction D. Diakonov, V. Petrov, and M. Polyakov, Z. Phys. A 359 (1997) 305. Splitting ~180 MeV S I3I3 Input A chiral soliton model for an anti-decuplet of 4 quarks plus an anti-quark gives specific estimates for masses and widths. The baryons at the corners are exotic.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 First Evidence for the  + : LEPS at Spring-8 in M= 1540±10±5 MeV  < 25 MeV at 90% C.L. Bump significant claimed as 4.6 inimum 5 quark content (uudds)  Mass and width consistent with chiral soliton model prediction.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 A Plethora of   Claims Followed-e.g., CLAS M(nK + ) CLAS fit SAPHIR M(nK + ) (fit) More Evidence for   e.g.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Summary of Positive Claims for  

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 (LEPS) Inconsistencies in M θ and Γ θ ? Width of θ + (1540)? Two “positive” experiments: HERMES: Γ θ = 17 9  2 MeV ZEUS: Γ θ = 8  4 MeV K + N PWA indicates Γ θ < 1 MeV M(nK+)≠ M(pK s )?

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 However, there are now many high statistics negative results e.g., For the K s p mass distributions seen in BaBar- the  c is the only clear structure 1.44 – 1.60 GeV/c GeV/c – 1.8 GeV/c – 3.0 GeV/c 2 Observed Ratio (  + (1540)/ *(1520)) <0.01 at 90% c.l.  c (~98,000 evts) cc  + (1540)

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Examples of Negative Results for    elle Observed Ratio (+(1540)/*(1520)) <0.02 at 90% c.l. 155fb -1  (1520) nothing m(GeV) pK - pK S

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 More Examples of Negative Searches for  + Hera-B M(pK s ) Θ + (1540) CDF M(pK s ) Aleph

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Summary of Negative Results K + N Scattering results exclude  + widths greater than a few MeV. Widths less than about 1 MeV are possible.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Negative Results in Perspective Assume pentaquarks have J= ½ expect B F(   +  pK s 0 ) = 25% expect B F(  5 --   -  - ) ~ 50% B F for  5 -,  5 0 very unclear If pentaquark production follows the trend for ordinary baryon production then we expect: ~ 8x10 -4  5 + per qq event ~ 4x10 -5  5 -- per qq event Limits are below expectations;  5 + : 1.1x10 -4 (  = 8 MeV)   -- : 2x10 -5 (  = 18 MeV) But… Most positive results at lower energies How unusual is the exotic production mechanism? (1520) may not be a reliable guide

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 So…do pentaquarks (especially the  + (1540)) exist?? “Expected” in QCD… Things that are not forbidden are compulsory! “Predicted” by chiral soliton model, which also predicts other exotic states. Spin, parity and mass may distinguish between models. If it exists, can provide a clear window beyond the naïve quark model. BUT…existence is an experimental question! Experimental situation is, at best, equivocal. Need new high statistics experiments, especially in electro & photo production. Look for new results soon from CLAS, HERMES, COSY-TOF, KEK E559.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Update on Neutrinos  By RICH02, it was clear that neutrinos oscillate.  It has now been further confirmed…. Neutrinos really do have small but finite masses!  First clear confirmation of physics beyond SM A triumph for the large water RICH detectors!

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Major Neutrino Sources from Space 1.Solar: From nuclear fusion All e Low energy….E <20 MeV 2.Atmospheric: From cosmic rays hitting the atmosphere L ~ 20 km L ~ 10 4 km  Earth E ~ 300 MeV - 2 GeV Super-K  p, He e e /   1/2 e   e P      sin 2 2  sin 2 (1.27  m 2 L/E) If Neutrinos have mass, a mixing formalism much like that for quark mixing applies, so that

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Super-Kamiokande SK-I: Nov 2001 Accident SK-II: Period'96-'01'03-'05 #PMTs11,1465,182 Photo Coverage 40 %19 % Light yield~6 p.e./MeV~2.8 p.e/MeV Energy threshold5.0 MeV8.0 MeV 50K Ton H 2 O 1 km underground Full reconstruction xcellent/e separation via ring width.

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 The Sudbury Neutrino Observatory 2092 meters deep underground 1000 tons of ultra-pure D 2 O in a 12 meter diameter acrylic vessel 7000 tons of ultra-pure H 2 O as shield 9500 PMTs mounted on a 18 meter diameter frame 40 helium proportional counters with total length of 398 m

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Analysis of SuperKamiokande–I from Atmosphere ~15km ~13000km~500km    2-flavor oscillations Null oscillation Best fit sin 2 2  =1.0,  m 2 =2.1x10 -3 eV 2  2 = 175.2/177 dof 90% C.L. region: sin 2 2  > 0.92, 1.5 <  m 2 < 3.4x10 -3 eV 2 Zenith angle distributions

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Neutrino interactions in SNO e−e− e−e− n Only e, Good measurement of E, Weak angle correlation 1-1/3cos  ⊙  e ( μ +  ), Some energy information Strong angle correlation Low statistics  e + μ + , No angle and energy information after thermalization

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 First “Salt” Results from SNO Enhanced NC detection 8/01-9/03

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 Neutrino Highlights as of 2004 Neutrino oscillations firmly established!  Solar  m 2 12 = ( )10 -3 eV 2  tan 2  12 = large but not maximal.  Atmospheric:  m 2 23 = (2.40.4)10 -3 eV 2  sin 2 2 23 > 90%CL maximal.  From global fit: sin 2 2 13 < 90%CL  Lots more to come with Enhanced Neutron Detection in SNO Long baseline accelerator and reactor experiments   decay and neutrino-less  decay experiments

Blair Ratcliff, SLACRICH2004, Playa Del Carmen, Mexico, Nov-Dec 2004 The Past and the Future-Reprise Since RICH02: Lots of exciting new data with RICH detectors. Scope of Physics with RICH is extremely broad and diverse.  Technique of choice when very high quality PID is required.  Use of water or natural media (that ice/water/atmosphere) as radiators allows the construction of massive instruments with excellent performance for neutrino and astroparticle physics  Provides excellent /e separation in Heavy Ion physics  Only major experimental arena is un-RICH’ed is the high energy frontier (Fermilab/LHC/ILC).  Physics with RICH will remain a forefront activity for the future.  There will be many opportunities for those in the audience to attempt to review this great physics at future RICH conferences.