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BTeV Physics Reach LHC 2003 Symposium K. Honscheid Ohio State University

BTeV Physics Reach LHC 2003 Symposium K. Honscheid Ohio State University. B Physics Today. CKM Picture okay CP Violation observed No conflict with SM. sin(2 b ) = 0.734 +/- 0.054. Surprising B Physics. >10 11 b hadrons (including B s ). B Physics at Hadron Colliders.

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BTeV Physics Reach LHC 2003 Symposium K. Honscheid Ohio State University

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  1. BTeV Physics Reach LHC 2003 Symposium K. Honscheid Ohio State University LHC2003K. Honscheid Ohio State

  2. B Physics Today • CKM Picture okay • CP Violation observed • No conflict with SM sin(2b) = 0.734 +/- 0.054 LHC2003K. Honscheid Ohio State

  3. Surprising B Physics >1011 b hadrons (including Bs) LHC2003K. Honscheid Ohio State

  4. B Physics at Hadron Colliders • The Tevatron as b (and c) source • b cross section ~100 mb, c cross section ~1000 mb • b fraction 2x10-3 • Inst. Luminosity 2x1032 • Bunch spacing 132 ns (396 ns) • Int./crossing <2> (<6>) • Luminous region sz = 30 cm • Forward Geometry 2x1011 b pairs/year bg b production angle b production angle LHC2003K. Honscheid Ohio State

  5. Pixel Detector RICH Detector Vacuum Vessel Gas (C4F10) + Liquid Radiator (C5F12) HPD + PMT read-out PbWO4 EM Calorimeter • 60 pixel planes • inside magnet • s = 5-10 mm 10500 crystals 220 mm long, 28x28 mm2 Beam Line p/K/p separation up to 70 GeV/c e/m separation at low momenta s(h->gg) ~ 5 MeV s(p->gg) ~ 3 MeV Proper time resolution: 46 fs CLEO/BaBar/BELLE-like performance in a hadron Collider environment! The BTeV Detector LHC2003K. Honscheid Ohio State

  6. Decay efficiency(%) Decay efficiency(%) B p+p-63 Bo K+p- 63 Bs DsK 74 Bo J/y Ks 50 B- DoK-70 Bs J/yK* 68 B- Ksp-27 Bo K*g 40 Efficiencies and Tagging • For a requirement of at least 2 tracks detached by more than 6s, we trigger on only 1% of the beam crossings and achieve the following trigger efficiencies for these states (<2> int. per crossing): • e efficiency; D  Dilution or (Nright-Nwrong)/(Nright+Nwrong) • Effective tagging efficiency  eD2 • Extensive study for BTeV uses • Opposite sign K± • Jet Charge • Same side p± (for Bo) or K± for (Bs) • Leptons • Conclusion: eD2 (Bo) = 0.10, eD2 (Bs) = 0.13, difference due to same side tagging LHC2003K. Honscheid Ohio State

  7. The Physics Goals • There is New Physics out there: • Baryon Asymmetry of Universe & by Dark Matter • Hierarchy problem • Plethora of fundamental parameters • … • BTeV is in a unique position to: • Perform precision measurements of CKM Elements withsmall model dependence. • Search for New Physics via CP phases • Search for New Physics via Rare Decays • Help interpret new results found elsewhere (LHC, neutrinos) • Complete a broad program in heavy flavor physics • Weak decay processes, B’s, polarization, Dalitz plots, QCD… • Semileptonic decays including Lb • b & c quark Production • Structure: B baryon states • Bc decays LHC2003K. Honscheid Ohio State

  8. Part 1: Is the CKM Picture correct? • Use different sets of measurements to define apex of triangle (adopted from Peskin) • Also have eK (CP in KL system) Bd mixing phase Magnitudes Bs mixing phase Can also measure gvia B-DoK- LHC2003K. Honscheid Ohio State

  9. Measuring aUsing Borp  p+p-po • A Dalitz Plot analysis gives both sin(2a) and cos(2a)(Snyder & Quinn) • Measured branching ratios are: • B(B-rop-) = ~10-5 • B(Bor-p+ + r+p-) = ~3x10-5 • B(Boropo) <0.5x10-5 • Snyder & Quinn showed that 1000-2000 tagged events are sufficient • Not easy to measure • p0 reconstruction • Not easy to analyze • 9 parameter likelihood fit Nearly empty (r polarization) Slow p0’s Dalitz Plot for Borp LHC2003K. Honscheid Ohio State

  10. Yields for Borp • Based 9.9x106 background events • Bor+p- 5400 events, S/B = 4.1 • Boropo 780 events, S/B = 0.3 Boropo Signal Background po g g mB (GeV) LHC2003K. Honscheid Ohio State mB (GeV)

  11. minimum c2 non-resonant non-rp bkgrd resonant non-rp bkgrd Our Estimate of Accuracy on a • Geant simulation of Borp, (for 1.4x107 s) Example: 1000 Borp signal + backgrounds With input a=77.3o LHC2003K. Honscheid Ohio State

  12. 6 5 4 3 2 1 Bs Mixing (Vtd/Vts) • BTeV reaches sensitivity to xs of 80 in 3.2 years LHC2003K. Honscheid Ohio State

  13. Measuring c • In the SM the phases and magnitudes are correlated: • l = |Vus| = 0.2205±0.0018 • c is the phase of Vts -> Bs Mixing • Good: Bs->J/yf plus non-trivial angular analysis • Better: Bs -> CP eigenstate such asBsJ/yh() ,hgg,hrg Silva & Wolfenstein (hep-ph/9610208)Aleksan, Kayser & London LHC2003K. Honscheid Ohio State

  14. Measuring c II • BTeV can reconstruct h and h’ • Yield in one year • BsJ/y h: 2,800 events with S/B = 15 • BsJ/y h: 9,800 events with S/B = 30 • Error on sin(2c) = 0.024 • With c ~ 2o a precision measurement will require a few years. LHC2003K. Honscheid Ohio State

  15. Physics Reach (CKM) in 107 s LHC2003K. Honscheid Ohio State

  16. Part II: Search for New Physics For a nice overview see: S. Stone “BTeV Physics” athttp://doe-hep.hep.net/P5StoneMarch2003.pdf LHC2003K. Honscheid Ohio State

  17. First Example: Supersymmetry • Supersymmetry: In general 80 constants & 43 phases • MSSM: 2 phases (Nir, hep-ph/9911321) • New Physics in Bo mixing: qD,Bodecay: qA,Do mixing: fKp Difference  NP New Physics LHC2003K. Honscheid Ohio State

  18. Rare b Decays • Search for New Physics in Loop diagrams • New fermion like objects in addition to t, c or u • New Gauge-like objects in addition to W, Z or g • Inclusive Rare Decays including • bsg • bdg • bsl+l- • Exclusive Rare Decays such as • Brg, K*g • BK*l+l-Dalitz plot & polarization g, l+l- BoK*g LHC2003K. Honscheid Ohio State

  19. Yield, S/B for Rare b Decays LHC2003K. Honscheid Ohio State

  20. Ali et. al, hep-ph/9910221 Polarization in BoK*om+m- • BTeV data compared to Burdman et al calculation • Dilepton invariant mass distributions,forward-backward asymmetrydiscriminate among the SM and various supersymmetric theories.(Ali, Lunghi, Greub & Hiller, hep-ph/0112300) • One year for K*l+l-, enough to determine if New Physics is present LHC2003K. Honscheid Ohio State

  21. Second Example: Extra Dimensions • Aranda & Lorenzo Diaz-Cruz, “Flavor Symmetries in Extra Dimensions” (hep-ph/0207059) (Buras et al. hep-ph/0212143) • Extra spatial dimension is compactified at scale 1/R = 250 GeV on up • No effect on |Vub/Vcb|, DMd/DMs , sin(2b) Bs -> mm –100 –8% g +72% |Vtd| LHC2003K. Honscheid Ohio State

  22. Summary • Heavy quark physics at hadron colliders provides a unique opportunity to • measure fundamental parameters of the Standard Model with no or only small model dependence • discover new physics in CP violating amplitudes or rare decays. • interpret new phenomena found elsewhere (e.g. LHC) • Some scenarios are clear others will be a surpriseThis program requires a general purpose detector like BTeV with • an efficient, unbiased trigger and a high performance DAQ • a superb charged particle tracking system • good particle identification • excellent photon detection LHC2003K. Honscheid Ohio State

  23. Changes wrt Proposal in Event Yields & Sensitivities • We lost one arm, factor = 0.5 • We gained on dileptons • From RICH ID • in proposal we used only m+m-, now we include e+e- • factor = 2.4 (or 3.9), depending on whether analysis used single (dilepton) id • We gained on DAQ bandwidth, factor = 1.15 • Gained on eD2 for Bs only,factor = 1.3 LHC2003K. Honscheid Ohio State

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