1. CDF Run II Silicon John Zhou Rutgers University Z ee

2. CDF Run II Silicon– J.Zhou 11/19/2002 Run II! CDF Silicon Run II Motivation: tracking b quarks for Ütop ÜHiggs ÜCP Violation ÜExotics Run II as of end of October ÜLarge fraction of data were taken with silicon ÜAchieving higher silicon inclusion efficiency month by month

3. CDF Run II Silicon– J.Zhou 11/19/2002 Silicon Overview 8 Layers, 704 ladders, 722432 Chans ÜLayer 00 (L00): 1 Single Sided layer ÜSVXII: 5 Double Sided Layers ÜISL: 2 Double Sided Layers One of largest and most complex silicon system ever built SVX-3 Chip

4. CDF Run II Silicon– J.Zhou 11/19/2002 SVXII Barrels 5 DS Layers (3 90 o, 2 1.2 o ), 2.5 < r < 10.6 cm, l = 0.9 m, greatly enhanced coverage 360 ladders, 405504 Chan. Standalone 3D tracking “Displaced track” trigger

5. CDF Run II Silicon– J.Zhou 11/19/2002 The ISL doubles the pseudorapidity range for b tagging and lepton id. Linking COT to the SVX for optimal tracking performance Extends tracking to |  |=2 2 DS 1.2 o layers, r = 20,28 cm, l = 1.9 m! 296 ladders, 303104 Chans 1 meter Intermediate Silicon Layers (ISL) 1 m

6. CDF Run II Silicon– J.Zhou 11/19/2002 Layer 00: Beampipe Layer SS layer on beampipe 48 ladders, 13824 Chans Increases IP (Impact Parameter) resolution by factor of 2 at p T = 1 GeV/c Be beam pipe 2.2 cm silicon cables SVX inner bore Cooling tube channel C fiber support

7. CDF Run II Silicon– J.Zhou 11/19/2002 SVT Board (Chicago) More Silicon Projects Cables (Johns Hopkins) Secondary Vertex Trigger (Chicago) NSF at Power Supply (Johns Hopkins)

8. CDF Run II Silicon– J.Zhou 11/19/2002 Si Ladder inspection (Rutgers) SVT Board (UC) Si Burn-in System (Rutgers) Silicon Vertex Detector Si Burn-in Box (Rutgers) NSF at Sensor Testing Beam Testing Production Testing Burn-in Calibration Alignment Monitoring

9. CDF Run II Silicon– J.Zhou 11/19/2002 Jumper HV Problem Fixed Bus 4 HV Bus 4* Jumper did not hold high voltage ÜTakes signal, HV from phi side to z side ÜSignal/ground traces close to HV traces Found after ~20 hours of Burn-In crucial test Solution: Copper wire for HV traces

10. CDF Run II Silicon– J.Zhou 11/19/2002 Unable to cool central part of ISL: Solid blockage experienced Appears at Al elbows (glue blockage seen with boroscope) Laser successfully removed glue 9/12 lines so far, finish next long shutdown cooling problem ISL Laser Surgery

11. CDF Run II Silicon– J.Zhou 11/19/2002 Wirebond Failures possible cause found Loss of digital power on 13/360 SVXII Z sides Hypothesis: fatigue from Lorentz force  Bond I orthogonal to B ÜL1A rate  Resonance? ÜTests convincing Ongoing investigation ÜAging tests ongoing ÜReducing current and catching warning signs highest priority Protective measures implemented No new failure B  I pp ~ 160 mA

12. CDF Run II Silicon– J.Zhou 11/19/2002 Monitoring Silicon Performance Left: one chip of SVXII ladder causing spikes in ADC counts. ÜSolution: mask the chip Bottom: stuck bit 0 on the channel IDs on SVXII ladder caused by optical transmission. ÜSolution: replace the optical receiver

13. CDF Run II Silicon– J.Zhou 11/19/2002 Realistic Testing ÜPower supply delivery ÜISL blocked cooling ÜL00 noise ÜBit Errors Reality Check: chip power failure ÜBeam splash ÜHigh L1 rate Despite daunting challenges, currently 90% of ladders are powered and operating. Silicon Commissioning Summary

14. CDF Run II Silicon– J.Zhou 11/19/2002 Performance: Clusters Signal to Noise > 10 ÜSingle Hit  > 99% Stability ÜPedestal ÜNoise Feb 02 Mar Apr MayJun JulAug 1 ADC Pedestals 1 ADC Noise

15. CDF Run II Silicon– J.Zhou 11/19/2002 Calibration from Physics: J/  ICHEP 2002: c  = 458 ± 10 ± 11 µm

16. CDF Run II Silicon– J.Zhou 11/19/2002 Future: Run IIb Radiation Damage  Replace L00, SVXII (2005-2006) ÜImproved rad hardness to 15 fb -1 ÜEasier to build-fewer different parts ÜNew SVX4 Chip ÜDAQ etc mostly same as Run IIa 1 st Electrical Stave SVX-4 Chip

17. CDF Run II Silicon– J.Zhou 11/19/2002 Summary Silicon Commissioning near complete Maintenance ÜDetailed protection procedure in run control ÜGetting to the small and subtle problems, solving them ÜLessons learned and passed on ÜStill fair amount of work to do Most of the remaining problems are the hard ones… New things appear from time to time! CDF Run II Silicon performing well ÜProducing clusters and tracks ÜResults already in Summer 2002, preparing for Winter now Run IIb is on the way