1 / 23

The Heavy Flavor Physics Program at CDF

The Heavy Flavor Physics Program at CDF. http://www.physics.purdue.edu/~mjones/talks/mjones_Aug10_2005.ppt. Graduate Students. Matthew Jones (Assistant Professor) Gene Flanagan (New Postdoc) Kim Giolo (Advisor D. Bortoletto), Niharika Ranjan (Advisor M. Jones) Riei Ishizeki (Undergraduate).

valin
Télécharger la présentation

The Heavy Flavor Physics Program at CDF

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. The Heavy Flavor Physics Program at CDF http://www.physics.purdue.edu/~mjones/talks/mjones_Aug10_2005.ppt Graduate Students Matthew Jones (Assistant Professor) Gene Flanagan (New Postdoc) Kim Giolo (Advisor D. Bortoletto), Niharika Ranjan (Advisor M. Jones) Riei Ishizeki (Undergraduate) • Triggers and limitations • Trigger upgrade work • Particle identification • Physics program DOE Site Visit - Task G

  2. The CDF-II Heavy Flavor Program • Unique to CDF: • Hadronic trigger: 2 displaced tracks • Fully reconstructed B decays • Charm physics program • Lepton+displaced track (semileptonic decays) • Other important triggers for B-physics: • Two leptons (e+e- or +-) • Single lepton triggers DOE Site Visit - Task G

  3. Tevatron Performance Projections (Fermilab 2004 DOE Mini Review of Run II Upgrades) e-cooling observed (July 18) Stacktail cooling preparations Improved p production Peak luminosity (Aug 4): Weekly delivered luminosity is currently about 15 pb-1 Performance now exceeds projections Must prepare for DOE Site Visit - Task G

  4. CDF-II Trigger Limitations • Maximum Level 1 trigger rate: • Effectively limited to 27 kHz • Large fraction of rate from track triggers – many are fake • Level 2 processing time: • Slowest component is SVT • Dead time > 5% when L1 rate > 13 kHz • Requires pre-scaling level 1 triggers • Upgrade will allow L1 rates up to 23 kHz • Need to improve purity of Level 1 track triggers! DOE Site Visit - Task G

  5. Level 1 Track Trigger Patterns of hits in axial superlayers identify track segments Patterns of segments identify tracks at level 1 • High efficiency • Large fake track rate at high luminosity DOE Site Visit - Task G

  6. Level 1 Trigger Rates • Trigger rate as a function of luminosity: • terms result in unreliable extrapolations to high luminosity. “Fakes” Multiple interactions Physics cross section DOE Site Visit - Task G

  7. Level 1 Track Trigger Upgrade • Baseline XFT Upgrade: • Identify track segments in stereo superlayers • Confirm axial XFT tracks with additional stereo segments • New hardware: • XTC2 mezzanine card (UIUC) • Stereo finder module (Fermilab) • Stereo Linker Association Module (OSU) • Fiber installation (Baylor University) • Level 2 algorithms (UC Davis) • Purdue assumed responsibility of online integration and commissioning DOE Site Visit - Task G

  8. XFT Upgrade Configuration Ansley trigger cable (220 ft) Data @45MHz LVDS ~2 m copper Cable Data @33MHz (channel link) Neighboring cards connected over backplane ~10 m of cable to XTRP 168 TDC from COT axial layers 24+24 Axial Finders 24 SLAMs 24 Linkers XTC 3 crates 24 crates 3 crates New cable (~150ft) Optical Data ~45MHz 3d track data out. ~3m optical Cable @60.6MHz 12+12+12 Stereo Finders New TDC or XTC for stereo layers 2 crates Data to L2 DOE Site Visit - Task G

  9. Track Trigger Upgrade Commissioning • Integration and commissioning plan based on previous experience with Time-of-Flight • XTC2 mezzanine cards: • Integrated with the CDF-II DAQ system • Online calibration and offline analysis code • Now included in normal CDF-II data taking • Some failures identified through routine operation • Stereo finder and SLAM modules • Framework for integration with DAQ system • Provide several modes for testing, diagnostics and validation • Integration complete by early 2006 followed by commissioning/validation of new hardware DOE Site Visit - Task G

  10. New Level 1 Trigger Hardware • Full sensitivity of B0s mixing analysis obtained from fully reconstructed B-decays • Could exclude  ms < 25-30 ps-1 by 2009 • SLAM output allows new Level 1 triggers • Evolved over past year to include: • Fast list of tracks sent to Level 2 SVT trigger • Track fitting at Level 2 starts earlier • “Barrel Pointer” uses stereo track information • Drop tracks that don’t point into the right part of SVX-II • Shorter Level 2 execution time • Higher purity B-physics triggers: • Transverse mass  3D mass  Dedicated B0s trigger • Increase yield of fully reconstructed B0s decays DOE Site Visit - Task G

  11. New Trigger Hardware • Quantifying the benefits of new trigger hardware required new analysis techniques: • CDF Note 7356 (November 8, 2005) A Method for Extrapolating Trigger Rates to High Luminosities • Applied to hadronic B0s yield with new trigger hardware – also allows evaluation of luminosity leveling: • Fermilab-TM-2322-AD-E (May 2, 2005) Influence of Luminosity Leveling on the CDF-II B-Physics Program DOE Site Visit - Task G

  12. New Level 1 Trigger Hardware • Dedicated trigger for D+s + or BX • Can keep tracks with pT as low as 1.5 GeV • Exploit unique K+K- decay topology: • Two low pT tracks • Small opening angle • Exit detector with same z • 2.5 times the B0s yield compared with current trigger • Estimated L1 cross section: 13 b (2.6 kHz at L=200e30) • Require additional 2 GeV/c track within 120o • Further L1 trigger rate reduction DOE Site Visit - Task G

  13. Time-of-Flight Detector • Goal: 2 K- separation for pT<1.6 GeV/c • Achieved “100 ps” timing resolution goal • Working on precision measurements DOE Site Visit - Task G

  14. Time-of-Flight Detector Operations • Sub-project leader since 2001 (with G.Bauer, MIT) • Institutes currently involved: • MIT, INFN, Cantabria, University of Pennsylvania • Purdue: electronics, software, calibrations, organization (previously Penn responsibilities) • Inheriting responsibilities from other institutes: Tsukuba (2001) No resources from Penn after 2005 Korea (2003) MIT out in FY06 Reduced INFN • Purdue graduate students to help provide pager coverage and routine maintenance DOE Site Visit - Task G

  15. Time-of-Flight Reconstruction Purdue efforts continue to improve performance: • New clock translator module electronics built at Purdue • Installed January 2005, simplifies maintenance • Allows synchronization of TOF and CLC clock signals • Studies using photon transport Monte Carlo: • CDF Note 7620 (Jones, Ishizeki): Sources of Bias in Time-of-Flight Measurements • Precision alignment of the scintillator: • CDF Note 7693 (Jones): Deformations of the Scintillator in the Time-of-Flight System DOE Site Visit - Task G

  16. Heavy Flavor Analysis • B lifetime using fully reconstructed decays • Kim Giolo (thesis), Bortoletto (advisor) • K production associated with B0s fragmentation • M. Jones, with Denys Usynin and Joseph Kroll (Penn) • K production associated with D+s fragmentation • M. Jones, Niharika Ranjan thesis DOE Site Visit - Task G

  17. B lifetimes (Kim Giolo thesis, Bortoletto advisor – defended May, 2005) • SVT: Level 2 trigger on displaced tracks • Fully reconstructed B-decays • High statistics lifetime measurements: • 12130 B0 D,D3 candidates • 600 B0s Ds, Ds3 • Lifetimes significantly biased by the trigger • Results from spring ’05 using 360 pb-1: DOE Site Visit - Task G

  18. B0s-K correlations • Motivated by Same Side Kaon Tagging for B0s mixing: • Projections for D2 based on Pythia • Might be as large as 4% (TOF proposal) • Significant compared with opposite side tags: D2 = 1.6% • Need to quantify this for setting a limit or evaluating sensitivity • How well does Pythia describe the data? • Mostly concerned with kaons • Can’t measure dilution since B0s mixes • Compare particle yields around B-decays DOE Site Visit - Task G

  19. B0s-K correlations (with Denys Usynin – University of Pennsylvania thesis) • High statistics from semileptonic B decays • Use TOF + dE/dx to measure fractions of K,,p in a cone around candidate DOE Site Visit - Task G

  20. D+-K and D+s-K correlations (Niharika Ranjan thesis, Jones advisor) • Address many deficiencies of B0s-K analysis: • Much higher statistics • Can measure charge correlation directly • Fully reconstructed decays using D+,D+s+ DOE Site Visit - Task G

  21. Summary • Addressing challenges of good Tevatron performance: • Integration of Level 1 track trigger to be ready for data taking in 2006 • New Level 1 trigger hardware will maximize physics potential from hadronic B decays • Continuing contribution to CDF operations: • Time-of-Flight operations • Offline reconstruction and calibration development • Trigger analysis: planning for the future • Analysis making the most of these efforts: • Many use data sets based on hadronic triggers • Precision applications of particle identification DOE Site Visit - Task G

  22. Supplementary Material DOE Site Visit - Task G

  23. B0s Mixing Sensitivity See http://www-cdf.fnal.gov/physics/projections/ • Assumes improvements in tagging, mainly from Same Side Kaon Tag • Better vertex resolution (eg., reject some classes of SVX hits on tracks) • B0s yield depends on Tevatron performance, Level 1 track trigger, Level 2 SVT upgrades • Could exclude  ms < 25-30 ps-1 by 2009 • Does not include increase in statistics from new Level 1 triggers described here. DOE Site Visit - Task G

More Related