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TASK: Studies of CP violation in the family of BEAUTY HADRONS

Belle experiment. Tadeusz Lesiak IFJ PAN, Kraków. TASK: Studies of CP violation in the family of BEAUTY HADRONS (rare B decays; sensitivity to New Physics). OUTLINE: B-factory KEKB and Belle apparatus Results: recent highlights The Belle group at the IFJ PAN, Kraków. The Universe

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TASK: Studies of CP violation in the family of BEAUTY HADRONS

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  1. Belle experiment Tadeusz Lesiak IFJ PAN, Kraków TASK: Studies of CP violation in the family of BEAUTY HADRONS (rare B decays; sensitivity to New Physics) • OUTLINE: • B-factory KEKB and Belle apparatus • Results: recent highlights • The Belle group at the IFJ PAN, Kraków

  2. The Universe IS CP-asymmetric CP violation (CPV) :  absolute difference matter-antimatter Indispensable condition of baryogenesis • 1964-neutral kaons -first evidence for CP violationeffects small o(10-3) and plagued by theoretical uncertainties • B mesons expected to be a CPV-gold-mine • large effects o(1), B is heavy: theoretically clean, experimental signatures in rare decays B factories needed

  3. CP Violation in the Standard Model CPV due to a single irreducible phase in the quark mixing matrix Our task: measurement of angles (and sides) of the unitarity triangle (A few examples below) New physics  new phases The unitary triangle is sensitive to them

  4. Mt. Tsukuba KEKB Belle ~1 km in diameter B-factory at KEK 8 GeV (e-)and 3.5 GeV (e+) Luminosity:world record: 15.Feb.2005 1085pb-1/day ¼ 1.2M BB/day 19.Feb.2005 275 million pairs of B mesons analysed Second player: PEPII (SLAC); BaBar experiment

  5. Belle experiment 2 Assoc. Prof.:M. Różańska (team leader) ,T .Lesiak 2 Ph.D.: A.Bożek, H.Pałka 3 Electronics eng.: P.Kapusta, Z.Natkaniec, W.Ostrowicz 2 Ph.D. students: J. Brodzicka, A. Matyja 2 M.Sc. Students: J.Wiechczyński, D.Żardecki ¼ 400 collaborators 13 countries, 57 institutes

  6. Silicon Vertex Detector (SVD) Summer 2003 before after Main Krakow’s contributions: • HALNY - FADC readout modules for the SVD1 (1998) (financial support from Princetown) • Readout electronics for the SVD2 • Alignement (offline) of the SVD • Monitoring of the SVD data quality • Maintenance and operation T.Lesiak Belle experiment

  7. Determination of the sin 2 5417 events at 140 fb-1 MB [GeV/c2] 2001: First evidence of CPV outside of the K system T.Lesiak Belle experiment

  8. Determination of the sin 2 excellent agreement with the SM Alternative: Sin2 may be determined fromb stransitions (suppressed in the SM); MB[GeV/c2] Our group pioneered the study of this channel at Belle T.Lesiak Belle experiment

  9. Determination of the sin 2 b s : proceed via penguin diagrams;sensitive to the New Physics Time dependent asymmetries measured: T.Lesiak Belle experiment

  10. Direct CP violation: B K decays Combining with BaBaR’s result: 5 effect! 2003: B +- : first 3.2evidence for direct CP violation T.Lesiak Belle experiment

  11. Discovering new particles Mass consistent withMD+MD* A (DD*) molecule-like bound state? Other states: DsJ(2317), DsJ(2457), c’ T.Lesiak Belle experiment

  12. Analysis: local activities • Studies of exclusive decays of B mesons: - b s transitions: B K(*), B K(*), B f0 K(*) • - cs spectroscopy: B D(*) D(*) K, B Ds K, • BDs K0s • - B D   :(heavy fermions in the final state-> • sensitive to New Physics) • Studies of charm hadrons - production of prompt charmonia and double cc pairs - spectroscopy of the c(*) baryons • Production of ‘central’ Monte Carlo samples in Kraków T.Lesiak Belle experiment

  13. Future: SuperBelle & SuperKEKB • Gradually increase the luminosity up to L = 1036 cm-2 s-1 • Milestones: - to collect 109 B meson pairs by 2008 (L=1ab) • - then shutdown (14 months) • - 2010 start of SuperKEKB • - to reach 10ab by 2014 Our channels important • Physics goals:- detailed study of CPV phenomena: - dynamics of flavour - connection between the flavour physics and mass generation in the Standard Model - origin of baryogenesis - looking for New Physics; elucidation of SUSY breaking mechanism • The Belle detector needs a substantial upgrade to deal with the luminosity HUNDRED times higher than the current one • We participate in the R&D work (Project COPPER/FINESSE) T.Lesiak Belle experiment

  14. Budget • Our commitments = sacred rules of the Belle collab.: - each group must contribute to the hardware construction and maintenance /upgrades and to the general software (2-3 months/year in our case) - each author of publications must participate in experimental shifts at least every second year. Number of our shifts: 2003: 52(26+26), 2004: 50(32+18) (expert+non-expert shifts) - 7 meetings/year collaboration wide: videoconferences are useful but sometimes is necessary to show up in person • The substantial support from KEK: - small allowances while staying at KEK - fellowships: JSPS, Monbusho - purchases of the apparatus (equipment for the electronics Lab, setup for videoconferences; partially repaid by our hardware contributions) T.Lesiak Belle experiment

  15. Budget 1 EUR = 4 PLN • IFJ PAN (salaries only): 35 500 EUR (average 2003 & 2004) • Personal exchange (R-31):7000 EURO/year; includes our travels to KEK and costs of stayings of Belle visitors in Kraków (4persons/year; one month in total per year) • KBN grants:(4 in total since 1995) Last two: „Studies of B meson rare decays at Belle” • (scarse) participation in conferences: grants & R-31 • Financing R&D works from grants but it is against the KBN rules • SPUBs (International Special Programs) limited to CERN (and DESY) T.Lesiak Belle experiment

  16. SUMMARY • The KEKB is doing extremely well • (record holder of the luminosity; produced • more than 350 million pairs of B-meson) • The Belle collaboration (together with BaBar) provided first evidence for the CP violation in the sector of beauty hadrons • In spite of limited resources, the Belle group at IFJ PAN in Krakow has managed to contribute significantly to this success!

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