CMS Detector Global Status

1. Wesley H. Smith U. Wisconsin HCP2009 - Hadron Collider Physics Symposium Evian, November 16, 2009 Outline: Testing with Cosmics & Splash Events Detector & Analysis Performance Readiness for first collisions CMS Detector Global Status

2. CMS Detector Design CALORIMETERS Superconducting Coil,4 Tesla HCAL ECAL Plastic scintillator/brass sandwich 76k scintillating PbWO4 crystals Steel YOKE • Level-1 Trigger Output • Today: 50 kHz(eventually100 kHz) • Directly feeds Higher Level Trigger CPU farm TRACKER PixelsSilicon Microstrips 210 m2 of silicon sensors 9.6M (Str) & 66M (Pix) channels MUON ENDCAPS MUON BARREL Cathode Strip Chambers (CSC) Resistive Plate Drift Tube Resistive Plate Chambers (RPC) Chambers (RPC) Chambers (DT)

3. 2008 • Cosmics, Splashes & • Circulating Beams

4. CMS Minus End & Closure

5. Final Closure(3 Sept. 2008)

6. 2008: First Beam through CMS Halo Muons in CSCs and HB Beam Pickup (ch1) CMS Beam Condition Monitors (ch 3, 4) Point 5 Control Room CMS Centre Meyrin

7. ME-1 ME-2 ME-3 ME-4 ME+1 ME+2 ME+3 ME+4 Beam Halo Events in CMS EndcapCSC muon chambers

8. Circulating Beam: Beam Halo Events HCAL Endcap: un-captured (lhs) & captured beam (rhs)

9. CMS Continuous Operation:CRAFT - Cosmics Run at 4 T* *operating field of CMS is 3.8T • Ran CMS continuously for 6 weeks (Oct – Nov ’08) to gain operational experience, stability of infrastructure. • Collected ~300M cosmic events. • About 400 TB of data distributed widely. • Efficiency ~ 70% (24/7) • First analyses of these data used s/w release intended for 2008 data-taking & LHC grid infrastructure. • Re-reconstruction & analyses with more advanced versions of the release

10. CRAFT08: Performance Plots(> 20 papers being submitted to JINST) Muon Chambers Point Resolution Energy deposited by muons Alignment in Inner Tracker Distn of Mean Residuals ECAL total Si Trkr Modules Points- data TOBx 2.6 um radiative ionisation HCAL Bpix Modules PXBx 2.6 um 10

11. ’08-’09 Shutdown – CMS Activities • After cosmics run (Nov ‘08), detector was opened for maintenance & repair activities, installation of preshowersubdetector & CASTOR. • Work progressed according to the schedule laid down in Nov. 2008. • Major Accomplishments: • Removal, repair, and re-insertion of the forward pixel system • Installation and commissioning of the preshower (ES) • Completion of maintenance & (some) repairs of all sub-systems • Completion of the revision of the tracker cooling plant • Understanding of magnetic field in the return iron-yoke • Overpressure protection (new item) – occupy underground control room • Re-commissioning of CMS • Prepared software (CMSSW3) for 2009 data taking, improving stability & reliability of computing infrastructure • New TOSCA Field Map – agreement of data & MC now better than 2% • Large MC production & analysis exercise at 10 & 7 TeV (“October Exercise”) • CRAFT09: • 40 day global cosmic run July 23 – Sept. 1, 2009 • Mostly continuous with a few planned downtimes

12. 2009 so far • Cosmics & Splashes

13. Cosmic Data Taking: CRAFT09 CRAFT09:23.7-1.9.09:Collected 300M+ cosmic events with tracking detectors & field on (3.8T). (160 M with field = 0) Quality of data from, and performance of, CMS is equal or better than that in CRAFT08 24/7 Data-taking effic’y~ 80%. Possible to improve, e.g.on weekends e ~ 85-90%.

14. CRAFT09 Performance PT Comparison (B-Field): Stand-Alone Muons vs. Tracker Muons Subdetectors % Operational

15. CMS preliminary CRAFT09: Tracker availability • Silicon strip : 98.1% • Tracker Outer Barrel: 98.3% • T. Inner Barrel/T. Inner Disks 96.5% • T. EndCap+: 98.8% • T. EndCap-: 99.2% 1 control ring* 1 cooling ring* *will investigatepossibility of repairin long shutdown • Silicon Pixel: 98.5% • Barrel: 99.1% • Forward: 96.9 Strip map : working modules (green), disabled (white),not read-out (red), other (mainly missing HV blue)

16. CMS preliminary CRAFT09 Track finding efficiency for cosmic muons • Tag muon with tracks from μ chambers. • 2 track-finders: • Combinatorial Track Finder (will be used in collisions) • Cosmic Track Finder(simple algorithm tailored for single muon tracks provides cross check) CMS preliminary

17. CMS Preliminary CRAFT09 Tracker hit efficiency • Hit efficiency for Cosmic Muons • Efficiency in the various layers of Si tracker • Tracks searched for without considering layer to be investigated. • Track extrapolated into layer investigated • Hit searched for inexpected region • Eff’cy includingfaulty modules*: 98.2% • Eff’cy excluding knownfaulty modules*: 99.9% *not including recent lossof 50 modules (0.4%) dueto cooling incident • Data for field on & off * * *Excluding known faulty modules

18. CRAFT09: Barrel and Endcap RPC fully functional Barrel chamber HV scan: Hit efficiency as a function of High Voltage Shown for two thresholds On plateau: efficiency is independent of threshold: robust settings CMS preliminary CMS preliminary CRAFT09: RPC Signals • Efficiency at fixed HV(9.3kV) for two different thresholds.Robust operational conditions

19. CRAFT09 Endcap Muon CSC data: reconstructed yvsx in each station Borrowed LV supplies for a test -- turned back on later +z endcap From one run (110508, 11 Aug 2009) cm -z endcap cm 99% of chambers delivered data in CRAFT09 (cf. 96% in CRAFT08)

20. CRAFT09: All Level-1 Trigger algorithms used • DT, CSC, RPC muon triggers with cosmic timing • Also used: LHC timing and pointing roads in muon trigger • ECAL & HCAL based triggers with very low thresholds e HF jets -jets  ET/HT Multiple objects iso Tested steady long-term running at 80 kHz halo Thresholds & cuts adjusted to provide comparable rates Unused bits

21. L1 trigger performance(CRAFT09) • L1 Drift Tube Track Finder Muon candidates • efficiency vspT(threshold 10 GeV) • L1 eγ efficiency turn-on curve • Measurement using muon brems in crystals • Muon triggered events, requiring muon associated with ECAL e.m. cluster • Effcy. of 1, 5, 10 GevThr. trigger vs.EM cluster Et • Super-pointing sample • (LHC-like) • pT from tracker

22. CRAFT09 Data Acquisition All systems in, including Preshower detector > 4700 Filter units applications running on 672 PCs Efficient running with 80 kHz input rate Huge muon trigger rate*,DAQ/HLT/SM ok *Noise temporarily raised rate – automatic throttling keeps stability • ~1 kHz cosmics / calib + 80 kHz randoms • ~15 hours, ~ 4 109 events

23. CMS Splash Events Nov. ‘09 • LHC started to deliver beam shots to CMS on afternoon of Saturday, Nov. 7 • ~every 40 sec in 3 sessions • CMS collected 1105 splashes • Solenoid at 3.8T • Shielding closed • Silicon tracking systems off (strips & pixels) • Muon systems at reduced HV (CSC, DT, RPC) • Only downstream RPC endcap enabled • Calorimeters on • Trigger on ECAL (central  ring) • Silicon preshower detector on  NEW • CASTOR (5.1 < |η| < 6.55) calorimeter on  NEW • First ZDC (8.5 < |η|) channels on  NEW

24. Splash ‘09 Event Display • ECAL energy deposits in red, HCAL energy deposits in blue (light blue for HF and HO) Beam 2 RPC muon hits are in yellow, and CSC muon hits are in magenta. Note that CSC wires are also visible.

25. Splash ‘09 Event Display • ECAL energy deposits in red, Preshower in green, HCAL energy deposits in blue (light blue for HF and HO), RPC muon hits are in yellow, and CSC muon hits are in magenta. Beam 2

26. Splash ‘09 Event Display • ECAL energy deposits in red, HCAL energy deposits in blue (light blue for HF and HO), RPC muon hits are in yellow.

27. Splash ‘09: ECAL vs. HCAL Observed Energy • 721 Splash events in a wide range of beam intensity • Response in EndCap+ is lower than EndCap- due to particle losses from material in CMS EndCap+ Barrel EndCap- Millions of muons per event  1000’s of TeV/event!

28. HCAL Response: single Splash ’09 event HF- | | HB | HE | HF+ HE • Response in HCAL (HB/HE/HF) • No dead channels • 6 HF channels (out of 1728) masked in trigger • Includes several saturated towers Beam  Bottom 

29. Splash ‘09: HCAL HB Timing ϕ-dep. cable corr. η-dep. ToF corr. HCAL reconstructed (Rechit) time for barrel Left: Apply Splash08 measured η correction for splash vs. collision time-of-flight & cables to Splash09 data Right: Add ϕ correction for cables measured during first Splash09 data (Sat-Sun) to later (Mon) Splash09 data μ HB- HB+ 1 ns!

30. ECAL Response: 800 Splash ’09 events ECAL Endcap - (beam side) ECAL Endcap + • Average energy per crystal in ECAL • White regions are masked channels • 0.9% of total • one quarter may be recovered. • Use coarse trigger data to recover all but 0.15% • Energy modulations are combination of energy flow traversing CMS & geometry effects. • e.g. lower energy at large radii in the ECAL Endcap downstream to the beam direction is due to the ECAL barrel shield. • Average muon fluence is about 5 muons cm-2 η=-1.5 η=1.5 y [crystal index] η=-3.0 η=3.0 ECAL Barrel x [crystal index] ECAL Barrel η=1.5 Bottom CMS 2009 Prelim. η=0 η=-1.5 Beam  ϕ

31. ECAL Preshower Responseto single Splash ’09 event CMS 2009 Prelim. • Installed Spring ’09 • Successfully operated during all Splash ‘09 events • Number of muons per sensor shown • Flux modulations consistent with energy maps seen in ECAL Endcaps. • Isolated hot spots are attributed to muon radiation • Sensors cover 37.1 cm2 each →average muon fluence ~ 5 cm-2 Readout problem (now fixed) η=-1.65 η=-2.6 LV problem – 50% now fixed η=1.65 η=2.6

32. Now • Preparing for the 2009/2010 Run

33. Total calculated L1 rate 9 kHz (50 kHz capacity) Muons: Unprescaled at pT=9 GeV; L1 single μ thresh. at 7 GeV Also unprescaled L1/L2/L3 μ outputat pT=30/11/9 GeV Electrons: No isolation requirements at L1 Unprescaled at pT=20 GeV w/no isolation& at 15 GeV with loose track isolation Photons: No isolation requirements at L1 Unprescaled at pT=25 GeV with no isolation Jets: Unprescaled 1-Jet pT=110 GeV MinBias: Algorithms use HF-tower ET,HF ET ring sums, Ecal ET, & pixel triplets Ready for Collisions:Trigger Menu for 1031cm-2s-1 Higher Level Trig. Rates by Object • Jet: 18 Hz • MET & HT: 8 Hz • Muon: 37 Hz • Electron: 26 Hz • Photon: 23 Hz • B-Tau: 13 Hz • x-triggers: 11 Hz • MinBias: 8 Hz • Total: 145 Hz Planned HLT Rate 300 Hz (600 Hz capacity) <CPU time>/event = 42 ms (100 ms capacity)

34. Analysis Model in CMS CMS Analysis is performed on a globally distributed collection of computing facilities CERN CAF Tier-0 Tier-1 Computing Facilities are major repositories of MC & reconstructed data Tier-2 CAF Tier-1 Tier-1 Tier-1 Tier-1 Tier-2 Computing Facilities are half devoted to simulation half user analysis. Primary resource for analysis Tier-2 Tier-2 Tier-2 Tier-2 Tier-2 Tier-3 Tier-3 Computing Facilities are entirely controlled by the providing institution & used for analysis Tier-3 Tier-3 Tier-3 Tier-3 Tier-3 Tier-3

35. Computing Readiness • MC Production • Generated 760M full simulation events July-Oct, 2009 • For both 7 and 10 TeV analyses • Tier-1 & Tier-2 readiness • Closely monitored: much improvement in Tier-2 readiness • Intensively tested during 2-week “October Exercise” of analysis • 77 separate analyses w/230 participants, increment of 700K jobs • ~ 2000 data sample subscriptions, 900 TB from Tier-1’s to Tier-2’s 200k/day 50 sites Different colors for different Tier-2’s Ready & Working October Exercise 4 times average Not Ready Scheduled Downtime

36. Early Physics Program • Early beam - collisions, up to 10-20 pb-1 @ 7 TeV • Commission trigger, start “physics commissioning” – “rediscover SM”: • Physics objects; measure jet & lepton rates; observe W, Z, top &, of course, first look at possible extraordinary signatures… • 7 TeV, 10’s of pb-1: measure S.M., start searches • Approx per pb-1: 3000 Wl (l = e,); 300 Zll (l =e, );5 ttbar+X • Improved understanding of physics objects; jet energy scale from W jj′; extensive use (& understanding) of b-tagging • Measure/understand backgrounds to SUSY & Higgs searches • As data accumulates higher, look for excesses from SUSY& Z′ resonances.

37. Particle Multiplicities &B physics Charged Hadron Multiplicity in Minimum Bias pp Collisions at 900 GeV and 10 TeV (5k events) 900 GeV 10 TeV Analyses have been redone for 7 TeV – available soon • e.g. Exclusive B production with early data: • B+(0)→ J/yK+(*0) cross section & lifetime ratio for 10 pb-1 @ 10 TeV B+→ J/yK+ with 10 pb-1 10 TeV MJ/yK+

38. QCD: Jet Measurements • Startup inclusive jet measurement using kT & SISCone • Studying other algorithms – present intent to make anti-kT the default Inclusive jet cross-section uncertainties (SISCone) for 10 pb-1data @ 10 TeV Inclusive jet cross-section measurement (kT) for 10 pb-1data @ 10 TeV

39. W, Z s∙BR(10 pb-1, 10 TeV) W  en Z ee Z Selection ET > 20.0 GeV both e isolated 70 < Me,e< 110 GeV W Selection ET > 30.0 GeV Isolated e Use data driven methods e.g. tag and probe method to work out efficiencies from “data” syst. uncert: 2.4% + 10% for Ldt syst. uncert: 4.0% + 10% for Ldt;

40. Conclusions & Outlook • CMS closed after 10-month successful maintenance period & in “data-taking” state • Round-the-clock operation • Magnet is at operational field. • All sub-detectors operating • Took data in 2009 beam splash events • Data analyzed from cosmic & beam-splash running shows an aligned, calibrated detector with trigger & DAQ that is ready for physics • Computing and Software systems have been exercised to demonstrate readiness for data analysis • Physics planning & tools are ready for beam • We are ready and eager for first collisions!