1 / 38

Fermilab: b -Physics at CDF & D0

Fermilab: b -Physics at CDF & D0. Tevatron, detectors and collaborations running well. Many results. Luminosity since March 2001. 9 fb -1 delivered 12 fb -1 2012?. Heavy b-States & Search for Rare b-decays. S +/- , S * +/- Baryons - CDF

jennifer-bolton
Download Presentation

Fermilab: b -Physics at CDF & D0

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Fermilab: b-Physics at CDF & D0 Tevatron, detectors and collaborations running well. Many results. Luminosity since March 2001 • 9 fb-1 delivered • 12 fb-1 2012? PIC 2010 Karlsruhe

  2. Heavy b-States & Search for Rare b-decays S+/-, S*+/- Baryons - CDF Lc , Sc Baryon Spectroscopy – CDF Search for Bs m m – D0 & CDF Observation of Y(4140) in B+J/ψ φ K+ - CDF PIC 2010 Karlsruhe

  3. CDF Data PRL 99, 202001(2007) Integrated Luminosity = 1.1fb-1 3180 +/-60 events M(Lb) = 5619.7 +/- 1.2 +/- 1.2 MeV/c2 CDF Pub PRL 96, 202001(2006) PIC 2010 Karlsruhe

  4. CDF6.0 fb-1 New Data – New Analysis N(Lb)=16,300 PIC 2010 Karlsruhe

  5. PIC 2010 Karlsruhe

  6. PIC 2010 Karlsruhe

  7. Fitted Q-values and Resonance widths PIC 2010 Karlsruhe

  8. Charm Baryon Spectroscopy at CDFLc(2595), Lc(2625), Sc(2455) &Sc(2520) JP = 3/2+ JP=1/2+ PIC 2010 Karlsruhe

  9. Orbital Excitations (l =1) 2625 2595 2520 2455 2286 PIC 2010 Karlsruhe

  10. Motivation, Goals, Improvements PIC 2010 Karlsruhe

  11. Charm Baryon Spectra – CDF 2010 PIC 2010 Karlsruhe

  12. Charm Baryon Spectra – CDF 2010 2 1 Proj. on 1 2286 309 2595 3 Proj. on 3 Proj. on 2 PIC 2010 Karlsruhe

  13. PIC 2010 Karlsruhe

  14. PIC 2010 Karlsruhe

  15. Results PIC 2010 Karlsruhe

  16. Bs→mm • Standard Model rate well understood • Standard Model rate is small • New physics enhancements can be large New result first presented by D0 Fermilab Postdoc Masato Aoki at FPCP2010 SM BF: B(Bs→mm)=(3.6±0.3)*10-9 Buras, arXiv:0904.4917 Primary author of manuscript submitted to Physics Letters arXiv:1006.3469v1 hep/ex PIC 2010 Karlsruhe

  17. Signal and Background m m c m b Bs m p p m m c b b b p p p p c K b Bs p K m m sequential Signal double B→KK PIC 2010 Karlsruhe

  18. Background reduction pT (mm) MinimumpT (m) Minimum DCA Angle between momentum and direction Vertex c2c2 sidebands sidebands Signal MC + J/y K data and MC Signal MC + J/y K data and MC Signal MC + J/y K data and MC Signal MC + J/y K data and MC Flight length significance Signal MC + J/y K data and MC Signal MC + J/y K data and MC sidebands sidebands sidebands sidebands m m SV PV 18 PIC 2010 Karlsruhe

  19. Background reduction m pT (mm) Minimum pT (m) m Minimum DCA SV Angle between momentum and direction Vertex c2 Dave Butler PV Flight length significance PIC 2010 Karlsruhe

  20. Background reduction Bayesian Neural Network B+→J/y K+ Calibration sample Expect ~3 signal events in our data with these cuts Signal region PIC 2010 Karlsruhe

  21. Neural Net Distributions - CDF Distributions of the input variables for the Bsm m Neural Net search. Isolation • = ct • = cL3DMmm/Pmm Background from sidebands Pmm l /sl Da Signal from Monte Carlo L pT(m2) pTBs PIC Karlsruhe 2010 21 PIC 2010 Karlsruhe

  22. Neural Net Output ---- CDF Make cuts above 0.9 in NN output where the signal to background should be high. PIC 2010 Karlsruhe

  23. B→h+h- 10-20lbefore outer muon layers B-→D0mn, D0→K-p+ Matching variables m K After penetration + matching cuts PIC Karlsruhe 2010

  24. Signal extraction 2D fit to m(mm) and BNN BNN sequential m(mm) double m(mm) Background shape from BNN sideband, norm from m(mm)sidebands PIC 2010 Karlsruhe

  25. Comparisons Old Old: 1D just counting events in signal region New: 2D including shape in signal region ~40% improvement in expected limit New/Old m(mm) New m(mm) BNN PIC 2010 Karlsruhe

  26. Results – D0 In highest sensitivity region: 51 ± 4expected bkg events, 55 data events BF < 51 x 10-9 (95% CL) 14x SM Expected limit: 38 x 10-9 11x SM arXiv:1006.3469v1 [hep-ex] PIC 2010 Karlsruhe

  27. New CDF Update Results – Prelim BRs PIC 2010 Karlsruhe

  28. Have a new limit based on 6.1 fb-1 4.6 times more data than last pub 2.4 times sensitivity of last pub Includes many improvements 33% reduction in KK background at same efficiency 40% improvement from 2D fitting Next steps More data Design variables to target dominant background of gluon fusion bb production where both B mesons decay semileptonically. Present Future PIC 2010 Karlsruhe

  29. Y(4140) Observation at CDF CDF reports evidence for a particle that decays to J/yfwith J/y to m+m- and f to K+K-. Such a state is exotic, meaning other such states that decay to two heavy charmonium states and have not been confirmed. The mass and estimated number of events are: 4143.4 +2.9/- 3.0(stat) +/- 0.6(syst) MeV, with 19+/-6 events. They quote the statistical significance slightly exceeds 5 s. A second structure of significance 3.1s is also reported with a mass and width of 4274.4 +8.4/-6.7 MeV and 32.3 +21.9/-15.3 MeV with a yield of 22+/-8 events. PIC 2010 Karlsruhe

  30. Summary Excellent progress on Sb+/- and excited states with new data and high statistics. CDF CDF new data and new analysis of Sc and Lc charmed baryons. Congratulations to CDF and the Karlsruhe group. New lower limits on the upper limit to the branching ratio for Bs m m. CDF & D0. New exotic state X(4140)  y(m+m-) f(K+K-)reported by CDF. PIC 2010 Karlsruhe

  31. Backup PIC 2010 Karlsruhe

  32. PIC 2010 Karlsruhe

  33. CDF Discovery of Sb&Sb* (2006) 1.1 fb-1 PRL 99,202001 (2007) PIC 2010 Karlsruhe

  34. Mass Splittings in Sb and S*b J. L. Rosner, Phys. Rev D 75, 013009 (2007) PIC 2010 Karlsruhe

  35. Fitting Strategy PIC 2010 Karlsruhe

  36. Systematic Uncertainties PIC 2010 Karlsruhe

  37. New Update from CDF – 3.7 fb-1 - Bs , Bd →mm Previous publication: CDF Collaboration; T. Aaltonen, et al., Phys. Rev. Lett. 100, 101802 2008) BRs for Bs(Bd) < 5.8 x10-8 (<1.8 x 10-8)  m+ m- 95% CL with 2fb-1 of integrated luminosity. 3.7 fb-1 Increased data sample: Increased size of data sample; Increased trigger acceptance. Two regions of m trigger acceptance: |h| <0.6with PT > 1.4 GeV/c [CMU-CMU] and 0.6 <|h| <1.0with PT > 2.0 GeV/c [CMU-CMX]. Offline reconstruction improvements: PIC 2010 Karlsruhe

  38. CDF Neural Net Event Selection PIC 2010 Karlsruhe

More Related