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ТЯЖЕЛЫЕ ФЛЭЙВОРЫ и КХД на T эватроне

ТЯЖЕЛЫЕ ФЛЭЙВОРЫ и КХД на T эватроне. Результаты коллабораций DØ и CDF за последний год. ТФ на T эватроне. Результаты коллабораций DØ и CDF за последний год. n (2S+1) L J.  (4415).  (4160).  (4040). χ c2 ′.  (3770). 2 M(D).

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ТЯЖЕЛЫЕ ФЛЭЙВОРЫ и КХД на T эватроне

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  1. ТЯЖЕЛЫЕ ФЛЭЙВОРЫиКХД на Tэватроне Результаты коллабораций DØ и CDF за последний год

  2. ТФ наTэватроне Результаты коллабораций DØ и CDF за последний год

  3. n(2S+1)LJ (4415) (4160) (4040) χc2′ (3770) 2 M(D) ′ ηc′ χc2 hc χc1 c χc0 J/ ηc c recently measured Quantum numbers n radial quantum number S total spin of qq L relative orbital mom. L = 0, 1, 2 → S, P, D J = S + L P = (–1)L+1 parity C = (–1)L+S charge conj. Charmonia • Many empty slots to fill • Expected broad states • decaying to DD, DD*, D*D* • All statesobserved • Good agreement with • QCD predictions

  4. Neutral cc-like states: q c q c q c π q c D D(*) c c c g c conventional molecular tetraquark hybrid • If properties conventional • If empty slot in cc spectrum • Meson and antimeson loosely bound • by pion exchange • Mass ≈ sum of meson masses • Decay: dissociation into constituent mesons • „Coloured” quarks tightly bound • by gluon exchange • Decay:rearrange into „white” mesons → dissociation • Lattice QCD: hybrids > 4.2GeV • Possible exotic JPC: 0+-, 1-+, 2+-… • Large hadronic transitions (ψππ, ψω,…)

  5. cc-like exotic states neutral X and Y charged Z

  6. missing states Bottomonia • Below BB threshold: Υ(nS) χbJ(nP) observed • ηb(nS) hb(nP) missing [can be observed via transtions from Y(nS)] • Hadronic transitions via π0, η, ππ, ω emission • Electric dipole transitions • Magnetic dipole transitions

  7. B decay diagrams

  8. КХДна Tэватроне Результаты коллабораций DØ и CDF за последний год

  9. Kinematical regions inx - Q**2 plane CTEQ6.1 gluon uncertainty high pT  hard partonic scattering kinematic plane • Sensitive to: • strong coupling constant • proton’s parton content  unique sensitivity to high-x gluon • dynamics of interaction- validity of approximations (NLO, LLA, …)- QCD vs. new physical phenomena

  10. . Jets

  11. Jets and Parent Partons largest high pT cross sectionat a hadron collider  highest energy reach Unique sensitivity to new physics: - new particles decaying to jets, - quark compositeness, - extra dimensions, - …(?)… jet xT jet In the absence of new physics: theory @NLO is reliable (±10%)  Precision phenomenology - sensitivity to PDFs  high-x gluon- sensitive to

  12. Inclusive Jets pT (GeV) pT (GeV) Phys. Rev. Lett. 101, 062001 (2008) Phys. Rev. D 78, 052006 (2008) • benefit from: • high luminosity in Run II • increased Run II cm energy  high pT • hard work on jet energy calibration steeply falling pT spectrum: 1% error in jet energy calibration  5—10% (10—25%) central (forward) x-section

  13. Inclusive Jets • High precision results • Consistency between CDF/D0 • well-described by NLO pQCD • experimental uncertainties: smaller than PDF uncertainties!! • data favor lower edge of CTEQ PDF uncertainties at high pT • shape well described by MRST2004 • data are used in PDF fits: • Included in MSTW2008 PDFs • Soon: in forthcoming CTEQ results

  14. Inclusive Jets • high precision results • consistency between CDF/D0 • well-described by NLO pQCD • experimental uncertainties: smaller than PDF uncertainties!! •  sensitive to distinguish between PDFs CTEQ6.5M PDFs • data are used in PDF fits: • included in MSTW2008 PDFs • at work: forthcoming CTEQ PDFs pT (GeV)

  15. Dijet Mass Distribution Phys. Rev. D 79, 112002   central dijet production |y|<1 • test pQCD predictions • sensitive to new particles decaying into dijets: excited quarks, Z’, W’, Randall-Sundrum gravitons, color-octet, techni-rho, axigluons, colorons • data with Mjj > 1.2 TeV! all described by NLO pQCD • no indications for resonances set limits on new particles

  16. Dijet Mass Spectrum in six |y|-max regions 0<|y|-max<2.4 Extend QCD test to forward region • data with Mjj > 1.2 TeV! described by NLO pQCD

  17. Dijet Mass Spectrum in six |y|-max regions 0<|y|-max<2.4 Extend QCD test to forward region • data with Mjj > 1.2 TeV! described by NLO pQCD • no indications for resonances •  PDF sensitivity at large |y|-max • CTEQ6.6 prediction too high • MSTW2008 consistent w/ data (but correlation of experimental and PDF uncertainties!)

  18. Dijet Angular Distribution • variable: • at LO, related to CM scattering angle • flat for Rutherford scattering • slightly shaped in QCD • new physics, like - quark compositeness - extra spatial dimensions enhancements at low large y small y

  19. Dijet Angular Distribution •  normalized distribution • reduced experimental • and theoretical uncertainties Measurement for dijet masses from 0.25 TeV to >1.1 TeV

  20. Dijet Angular Distribution •  normalized distribution • reduced experimental • and theoretical uncertainties Measurement for dijet masses from 0.25 TeV to >1.1 TeV Submitted to Phys. Rev. Lett. First time: Rutherford experiment above 1TeV

  21. Dijet Angular DistributionNew Physics Limits • At highest possible energy: • Probing quark substructure • Sensitive to extra spatial dimensions- virtual exchange of KK excitation of graviton (ADD LED) - virtual KK excitation of gluon (TeV-1 ED) CDF: D0: • detector-level comparison of data and PYTHIA: study ratio • R = N( <15)/N( >15) • for 550 < Mjj < 950 GeV • From pseudo experiments: Feldman Cousins limits @95%CL • Quark Compositeness Λ > 2.4 TeV • Use full shape • of corrected data • Bayesian and methods @95%CL • Quark Compositeness Λ > 2.9TeV • ADD LED (GRW) Ms > 1.6 TeV • TeV-1 ED Mc > 1.6 TeV all: most stringent limits!

  22. jet jet Strong Coupling Constant inclusive jet cross section is sensitive to previous CDF result from Run I: PRL88, 042001 (2002)

  23. Strong Coupling Constant • From 22 (out of 110) inclusive jet cross section data points at 50<pT<145 GeV •  Exclude data points with • - NLO + 2-loop threshold corrections • - MSTW2008NNLO PDFs • - Extend results from HERA to high pT

  24. . Vector Boson + Jets Fixed-order: NLO LO + Parton Shower Matched Tree-Level + PS Backgrounds to New Physics

  25. q q g Z Vector Boson + Jet • relevant to other high-multiplicity processes • background to Higgs • test “matched” predictions  critical to Tevatron / LHC physics • Provide detailed measurements of pT and angular distributionsof vector boson and jet • test perturbative QCD calculations • testing and tuning of phenomenological models

  26. Z + (1, 2) jets pT -jet Inclusive jet pT spectrum 1st and 2nd leading jet pT

  27. Z + (1, 2, 3) jets  pT -jet • Measurement of 1st, 2nd and 3rd jet pT in Z events: • normalize to inclusive Z production (cancel some uncertainties) • compare to pQCD @ LO / NLO Phys. Lett. B 669, 278 (2008) Leading jet in Z + jet + X Second jet in Z + 2jet + X Third jet in Z + 3jet + X

  28. Z + (1, 2, 3) jets  pT -jet Ratios of data and different MC generators  favor ALPGEN w/ low scale Leading jet in Z + jet + X Second jet in Z + 2jet + X Third jet in Z + 3jet + X

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