Belle II Science and Overall Project Tom Browder University of Hawaii

19-20 March 20142T. Browder, US Belle II Independent Project Review B Mesons: “Laboratory Rats of the Weak Interaction” Exotic bound state of matter and antimatter (hydrogen-like) b quark mass ~ 5x proton mass Lifetime ~ 1.5ps 1987: A neutral B meson can transform into its anti- particle, “B-Bbar mixing” 2001: Asymmetry between matter and anti-matter found in B meson weak decays. (B Factories)

e + source Ares RF cavity Belle detector World record: L = 2.1 x /cm 2 /sec SCC RF(HER) ARES(LER) Starting point: Belle and The KEKB Collider (A facility located in Tsukuba, Japan) 8 x 3.5 GeV 22 mrad crossing angle March 2014US Belle II Independent Project Review3 ~2 Billion B Mesons produced

19-20 March 20144T. Browder, US Belle II Independent Project Review A history of rich, diverse and productive science outcomes B Factories: BaBar and Belle each produced >400 journal publications across a broad range of physics topics (b, c, tau, 2-photon, ….) Many important discoveries: – New matter-antimatter asymmetries, new weak interaction couplings (b  s, d, u); new states of matter etc. Recognition: the 2008 Nobel Prize in Physics

19-20 March 20145T. Browder, US Belle II Independent Project Review M. KobayashiT. Maskawa 2008 Discoveries about weak interactions of quarks  Nobel Prizes J. CroninV. Fitch T.D. LeeC.N. Yang

19-20 March 20146T. Browder, US Belle II Independent Project Review To explore new physics: SuperKEKB/Belle II is the new international intensity frontier facility for B mesons, charm mesons and tau leptons. Different and complementary capabilities compared to existing facilities: e + e - vs proton-proton (LHC) From the movie “Particle Fever”

7 40 X higher luminosity KEKB to SuperKEKB Redesigned lattice to reduce the emittance (replaced short dipoles with longer ones, increase wiggler cycles ) Replace 3.1 km of LER with TiN-coated beam pipes with antechambers 8 new superconducting final focus magnets Upgrade positron capture section e - 2.6A e + 3.6A Injector Linac upgrade DR tunnel Low emittance RF electron gun Reinforced RF systems for higher beam currents $400M facility upgrade Belle II Detector is $50M US Belle II Independent Project Review Beam size is reduced to 50 nm in vertical, 1 micron in horizontal. Accelerator Facilities March 2014

8T. Browder, US Belle II Independent Project Review Overview of Belle II Detector electrons (7GeV) positrons (4GeV) KLong and muon detector: Resistive Plate Counter (barrel outer layers) Scintillator + WLSF + MPPC (end-caps, inner 2 barrel layers) Particle Identification Time-of-Propagation counter (barrel) Prox. focusing Aerogel RICH (fwd) Central Drift Chamber He(50%):C 2 H 6 (50%), small cells, long lever arm, fast electronics EM Calorimeter: CsI(Tl), waveform sampling (barrel) Pure CsI + waveform sampling (end-caps) Vertex Detector 2 layers DEPFET + 4 layers DSSD Beryllium beam pipe 2cm diameter ++Background commissioning detector

19-20 March 20149T. Browder, US Belle II Independent Project Review High Level Schedule including US Milestones Key dates at KEK: Phase I (No Final Focus Quads, No Belle Detector): Jan 2015 Phase II (Final Focus, Belle, no vertex detectors): Feb 2016 Phase III (Final Focus, Belle, vertex detectors): October 2016

19-20 March T. Browder, US Belle II Independent Project Review Belle II: A Truly International Team 599 Collaborators, 97 institutes, 23 countries

19-20 March T. Browder, US Belle II Independent Project Review U.S. Leadership in Belle II D. Asner, EB and FB rep from US J. Fast, TOP leader M. Schram, network coordinator, US rep CSG A. Schwartz, speakers committee

19-20 March T. Browder, US Belle II Independent Project Review Summary SuperKEKB upgrade construction nearing completion – First beams in 2015 – First physics run starts in late 2016 – ~$400M Japanese investment to upgrade accelerator Belle II – $50M upgrade so detection systems can operate with the much more intense particle beams and backgrounds – U.S. contributions target areas in which we have historically had leadership and which are vital to the physics program A diverse and productive science program awaits us – Unique international facility that will operate for over a decade

19-20 March T. Browder, US Belle II Independent Project Review Backup slides

19-20 March T. Browder, US Belle II Independent Project Review Latest Belle II Schedule

19-20 March T. Browder, US Belle II Independent Project Review SuperKEKB luminosity profile Goal of Belle II/SuperKEKB 9 months/year 20 days/month Commissioning starts in early Shutdown for upgrade Integrated luminosity (ab -1 ) Peak luminosity (cm -2 s -1 ) Calendar Year Belle/KEKB recorded ~1000 fb -1. Now change units to ab -1

19-20 March T. Browder, US Belle II Independent Project Review SuperKEKB is the e + e - intensity frontier 40 times higher luminosity   KEKB PEP-II

KEKB Design KEKB Achieved : with crab SuperKEKB Nano-Beam Energy (GeV) (LER/HER)3.5/ /7.0  y * (mm) 10/105.9/ /0.30  x * (mm) 330/ /120032/25  x (nm) 18/1818/243.2/5.3  y  x (%) 10.85/ /0.24  y (  m) /0.062 yy / /0.081  z (mm) /5 I beam (A)2.6/ / /2.6 N bunches Luminosity (10 34 cm -2 s -1 ) Parameters for KEKB and SuperKEKB Nano-beams are the key (vertical spot size is ~50nm !!) 17US Belle II Independent Project Review19-20 March 2014