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CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 1
CDFCDFPerformance and ImprovementsPerformance and Improvements
Detectors, Triggers, Offline, and Analysis AlgorithmsDetectors, Triggers, Offline, and Analysis Algorithms
CDF CollaborationCDF Collaboration
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 2
Data Taking EfficienciesData Taking Efficiencies
Initial Luminosity (1030 cm-1s-1) Data Taking Efficiency
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 6
Current StatusCurrent Statusandand
Preparation for FuturePreparation for Future
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 7
CDF DetectorsCDF Detectors
Performing very well.Even Run IIb Detectors! - Operational since early 2006
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 8
CDF DetectorsCDF Detectors
• Run IIb Upgrades: – Central Preshower Detector
• Replacing with a finer segmentation system• Electron tagger, / separation• Installed fall 2004
– Electromagnetic Timing• New system for rejecting beam-halo and cosmic ray• Searches with (e.g. GMSB SUSY, long-lived particles)• Installed fall 2004
For the future, tracking systems are our main concerns.
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 9
Tracking Performance: COT and SiliconTracking Performance: COT and Silicon
• COT Aging - Fully Recovered– Aging due to hydrocarbons
coating sense wires– Fixed by adding Oxygen– Fully recovered May 2004– 99.7% working!
• Silicon detector lifetime is a complex issue involving – Component failures
• ~93% powered; ~84% working + 4% recoverable in offline• Secondary vertex trigger requires 4 layers: 21 out of 24 wedges
– Beam incidents• lost ~2% of chips: conditions improved, but still concern
– Long-term radiation damage
COT Gain vs. Time
Jan.2002 Aug.2005
May 2004
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 10
Silicon DetectorsSilicon Detectors
• Radiation damage– > 90% of total radiation is due to collisions: NIM A514, 188-193 (2003)
– Bias voltage scans as luminosity accumulates• Study collected charge (hits on tracks) and mean noise• Measurements agree with predictions up to 1 fb-1.
• Efforts to increase the Silicon lifetime– Lowered Silicon operating temp. gradually from -6oC to -10oC.– Thermally isolated SVX from COT inert regions such that the silicon
can be kept cold during COT work.
Lifetime 0 10 fb-1 20 fb-1 30 fb-1 40 fb-18 fb-1
Predicted Silicon Lifetime
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 11
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 12
Data ReconstructionData Reconstruction
• Recently achieved 6 week turn-around time between data taking and availability of physics-quality data with final calibrations.– This reduced resource needs (person and computing).
• Reconstruction algorithms are stable since January 2005.– Incorporated Run II detector upgrades.– No major changes anticipated in the future.
Ave
. in
v. m
ass
at
Z p
eak
[G
eV]
Run Number (up to July 20, 2005) M(e+e-) [GeV/c2]
CDF Run2 Prelim.L=790 pb-1
CDF Run2 Prelim.L=790 pb-1
Data up toJuly 20, 2005
yellow band: ±0.5% E scale
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 13
Data ReconstructionData Reconstruction
• CDF Production executable is fast.– ~110 million events / week
– 50 streams: high pT e, , , jet, Hadronic B, J/ , J/ ee, ….
– The ave. executable time increases by x2.5 from Lpeak = 1x1032 cm-2s-1
to 3x1032 cm-2s-1. We have already demonstrated this capacity.– Plan to process all the data until the end of Run II at Fermilab.
Number of data events written to tape by Production Farm
Aug 23 - Sep 3, 2005
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 14
Monte Carlo Simulation and Production Monte Carlo Simulation and Production
• Detector simulation reaching maturity - matching data– Incorporated detector configuration changes with time– Incorporated multiple interactions for data instantaneous luminosity
• Increasing access to global computing resources (GRID philosophy) to match physics needs.– Running on worldwide computing clusters - shared with LHC
• ~100% of MC samples are generated outside of US.• Planning data analysis centers at remote sites
– Physics analyses produced with remotely located datasets– Italian inst.s, Karlsruhe: J/ lifetime, B tagging, Single top
– Worldwide computing resources transparent to physicists.
• Aim to support more computing with fewer FTEs
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 15
•Run IIa Level-1 Accept not achieved due to •higher than specified Silicon Readout and Level-2 Trigger execution times.
** Assume ~5% from readout and ~5% from L2 processing
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 25
Run IIb Project StatusRun IIb Project Status
• Trigger and DAQ Upgrades– Level-1 Track Trigger (XFT):
• Add z (stereo) info for 3D tracking - In production– COT TDC modification to achieve L2 rate of 1000 Hz (readout time)
• 12 out of 20 crates are operational.– Level 2 decision system: faster,flexible - operational since April 2005– Level 2 Silicon Vertex Trigger (SVT)
• Faster - 3 step upgrade: the first 2 steps are operational.– Event Builder: operational since August 2005– Level-3 Computing Farm
• 1st procurement(64 PCs) in place-replace current system in Nov’05• 2nd procurement(64 PCs) - ~Jan.06
– Data Logging (20 MB/s 60 MB/s)• 1st step operational (~35MB/s), complete by end of 2005
Installation & commissioning parasitically with minimal impact on operations.
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 26
Run IIb Upgrade StatusRun IIb Upgrade Status
• Very successful so far:– 85% complete– Will finish by early 2006
• Upgrade success due to:– Highly successful Run IIa detector/trigger design &
operation– Carefully targeted to specific high luminosity needs– This allowed for incremental and parasitic implementation
and commissioning with minimal impact on operations.– Some cases (e.g. COT TDC), instead of building new
detectors, we gradually improved the systems.
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 27
Physics Triggers for 3 x 10Physics Triggers for 3 x 103232 cm cm-2-2ss-1-1
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 28
Extrapolation to 3 x 10Extrapolation to 3 x 103232cmcm-1-1ss-1-1
at 3 x 1032 cm-2s-1
~3% of Level-2 bandwidth~50% of Level-2 bandwidth.
Reduce to ~10 % with XFT upgrade
• Triggers are sensitive to multiple interactions.• Measure cross section vs # of primary interaction vertices.• Calculate cross sec vs lum. using Poisson distribution of # of primary vertices.• Good agreement with bunch-by-bunch data.
Stereo confirmationof tracking triggers
Level-2 high pT electron Level-2 high pT muon (0.6 < || < 1.1)
Average luminosity (36 bunches)Bunch-by-bunch luminosity
a highly non-linear behavior
trigger rate = cross section x L
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 29
Extrapolation to 3 x 10Extrapolation to 3 x 103232cmcm-1-1ss-1-1
~1/3 of Level-2 bandwidth at 3x1032 cm-2s-1: studying further improvements
Studied triggers for “full” high pT physics program:~2/3 of bandwidth. Aim for 50% of bandwidth
Cross sections of high pT triggers (high pT e,,,jet,ET) with Level-1 upgradeCovers W, Z, Top, WH, ZH, HWW, SUSY (partial), LED, Z’
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 30
Physics Triggers at 3 x 10Physics Triggers at 3 x 103232 cm cm-2-2 s s-1-1
• Trigger Table in current operations is good to ~1.5 x 1032 cm-2s-1
– Kept improving as luminosity increases. Significant efforts!• Trigger Table for ~3 x 1032 cm-2s-1
– high pT physics program - aim for 50%– The remaining bandwidth will be given to B physics
• Strategy: Developed high purity triggers for high luminositywhile keeping inclusive heavy flavor triggers at low luminosity.
• Level-1,2 upgrades improve purity, reduce processing time.• Other tools being implemented:
– vetoing high multiplicity events
– Final decision on the trigger composition• based on physics priority
and purity of triggers
– Straw Trigger Table ready by October 2005. 0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0 2 4 6 8 10 12 14 16 18 20 22 24
66%34%
Lpeak = 3 x 1032
In 3.5 hours,L < 1.5 x 1032
hours
L(1032)
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 31
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 32
Concluding RemarksConcluding Remarks
• CDF experiment is operating well. Better than ever!– Typical data taking efficiencies in the mid 80%’s with increasing inst.
Luminosity and Run IIb commissioning– All detectors are in excellent conditions– Stable offline software– Established fast calibrations, data processing scheme– Good detector simulation– MC production at remote sites
3 step upgrade: first two steps complete and operationalAs expected, core of timing stays the same, but tails are significantly reduced.
Bigger improvements expected later.
SVT processing time (s)
Run 203624Sep.1 2005
Run 203325Aug.26 2005
CDF Performance and Improvements: Young-Kee Kim (U.Chicago), Sept.12 2005, P5 Meeting 37
Future B TriggersFuture B Triggers
• Current B triggers– High bandwidth tracks and leptons at L1, followed by SVT at L2.
• What we’ve done so far– Developed high purity triggers for high lum, while
keeping inclusive heavy flavor triggers at low lum.• 2 tracks - vetoing high multiplicity events• Transverse mass requirement• 2 tracks +
• For the future– XFT (L1) and SVT (L2) will improve purity and reduce L2 processing time.– Multi track combination - dedicated+track trigger.– Kinematic variable requirements with stereo information at L2.
• Upgraded L2 decision is extremely flexible (firmware).
• B program will not be fully active at peak lum, but we will continue to accumulate large hadronic B samples throughout the life of CDF.