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W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 1
CMS Detector Global StatusCMS Detector Global Status
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
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 2
CMS Detector DesignCMS Detector Design
MUON BARREL
CALORIMETERS
PixelsSilicon Microstrips210 m2 of silicon sensors9.6M (Str) & 66M (Pix) channels
ECAL76k scintillating PbWO4 crystals
Cathode Strip Chambers (CSC)Resistive Plate Chambers (RPC)
Drift Tube Chambers (DT)
Resistive Plate Chambers (RPC)
Superconducting Coil, 4 Tesla
Steel YOKE
TRACKER
MUONENDCAPS
HCALPlastic scintillator/brasssandwich
Level-1 Trigger Output• Today: 50 kHz
(eventually100 kHz)• Directly feeds Higher
Level Trigger CPU farm
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 3
20082008
Cosmics, Splashes &Circulating Beams
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 4
CMS Minus End & ClosureCMS Minus End & Closure
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 5
Final Closure(3 Sept. 2008)
Final Closure(3 Sept. 2008)
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 6
2008: First Beam through CMS2008: First Beam through CMS
Beam Pickup (ch1) CMS Beam Condition Monitors (ch 3, 4) Point 5 Control Room
CMS Centre Meyrin
Halo Muons in CSCs and HB
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 7
Beam Halo Events in CMS EndcapCSC muon chambers
Beam Halo Events in CMS EndcapCSC muon chambers
ME-4ME-3ME-2ME-1
ME+1 ME+2 ME+3 ME+4
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 8
Circulating Beam: Beam Halo EventsCirculating Beam: Beam Halo Events
HCAL Endcap: un-captured (lhs) & captured beam (rhs)
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 9
CMS Continuous Operation:CRAFT - Cosmics Run at 4 T*CMS Continuous Operation:
CRAFT - Cosmics Run at 4 T*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
*operating field of CMS is 3.8T
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 10
CRAFT08: Performance Plots(> 20 papers being submitted to JINST)CRAFT08: Performance Plots(> 20 papers being submitted to JINST)
Energy deposited by muonsEnergy deposited by muons
HCALHCAL
ECALECAL
radiativeradiativeionisationionisation
Points- dataPoints- data
totaltotal
10
Muon Chambers Point Resolution
Muon Chambers Point Resolution
Distn of Mean ResidualsDistn of Mean Residuals
Alignment in Inner Tracker Alignment in Inner Tracker
Si TrkrModulesSi Trkr
Modules
BpixModules
BpixModules
TOBx
2.6 um
PXBx
2.6 um
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 11
’08-’09 Shutdown – CMS Activities
’08-’09 Shutdown – CMS Activities
After cosmics run (Nov ‘08), detector was opened for maintenance & repair activities, installation of preshower subdetector & 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
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 12
2009 so far2009 so far
Cosmics & Splashes
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 13
Cosmic Data Taking: CRAFT09
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%.
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 14
Barrel Pixel
Endcap Pixel
Tib/TID
TOB
TEC+
TEC-
ECAL barrel
ECAL endcap
Preshower
HCAL barrel
HCALEndcap
HCAL Outer
HF
ZDC
DRIFT tubes
RPC barrel
RPC endcap
CSC
95% 96% 97% 98% 99% 100%
Percent Operational
CRAFT09 PerformanceCRAFT09 Performance
PT Comparison (B-Field): Stand-Alone Muons vs. Tracker Muons
Sub
dete
ctor
s
% Operational
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 15
CRAFT09: Tracker availabilityCRAFT09: 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
CMS preliminaryStrip map : working modules (green), disabled (white), not read-out (red), other (mainly missing HV blue)
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 16
CRAFT09 Track finding efficiency for cosmic muons
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 CMS preliminary
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 17
CRAFT09 Tracker hit efficiencyCRAFT09 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
CMS PreliminaryData for field on & off
*
*
*Excluding known faulty modules
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 18
CRAFT09: RPC SignalsCRAFT09: RPC Signals 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
Efficiency at fixed HV(9.3kV) for two different thresholds.Robust operational conditions
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 19
CRAFT09 Endcap Muon CSC data: reconstructed y vs x in each station
CRAFT09 Endcap Muon CSC data: reconstructed y vs x in each station
+z endcap
-z endcap
99% of chambers delivered data in CRAFT09 (cf. 96% in CRAFT08)
Borrowed LV supplies for a test -- turned back on laterFrom one run (110508, 11 Aug 2009)
cm
cm
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 20
HF jets -jets e
iso ET/HT Multiple
objects
Unused bits
halo
CRAFT09: All Level-1 Trigger algorithms used
CRAFT09: All Level-1 Trigger algorithms used
DT, CSC, RPC muon triggers with cosmic timingAlso used: LHC timing and pointing roads in muon triggerECAL & HCAL based triggers with very low thresholds
Thresholds & cuts adjusted to provide comparable rates
Tested steady long-term running at 80 kHz
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 21
L1 trigger performance(CRAFT09)
L1 trigger performance(CRAFT09)
L1 Drift Tube Track Finder Muon candidates• efficiency vs pT
(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
Super-pointing sample
(LHC-like)
pT from tracker
Effcy. of 1, 5, 10 Gev Thr.
trigger vs.EM
cluster Et
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 22
CRAFT09 Data AcquisitionCRAFT09 Data Acquisition
Efficient running with 80 kHz input rate
All systems in, including Preshower detector
> 4700 Filter units applications running
on 672 PCs
Huge muon trigger rate*,DAQ/HLT/SM ok
• ~1 kHz cosmics / calib + 80 kHz randoms• ~15 hours, ~ 4 109 events
*Noise temporarily raised rate – automatic throttling keeps stability
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 23
CMS Splash Events Nov. ‘09CMS 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
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 24
Beam 2
Splash ‘09 Event DisplaySplash ‘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, and CSC muon hits are in magenta.
Note that CSC wires are also visible.
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 25
Splash ‘09 Event DisplaySplash ‘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
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 26
Splash ‘09 Event DisplaySplash ‘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.
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 27
Splash ‘09: ECAL vs. HCAL Observed Energy
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
Barrel
EndCap+
EndCap-
Millions of muons per event 1000’s of TeV/event!
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 28
Bottom
Beam
HCAL Response: single Splash ’09 event
HCAL Response: single Splash ’09 event
• Response in HCAL (HB/HE/HF)• No dead channels
• 6 HF channels (out of 1728) masked in trigger• Includes several saturated towers
HF+HE HB HEHF- | || |
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 29
Splash ‘09: HCAL HB TimingSplash ‘09: HCAL HB TimingHCAL 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
η-dep. ToF corr.
HB+HB-μ
1 ns!
ϕ-dep. cable corr.
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 30
ECAL Response: 800 Splash ’09 events
ECAL Response: 800 Splash ’09 events
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
CMS 2009 Prelim.
ECAL Endcap - (beam side) ECAL Endcap +
ECAL BarrelECAL Barrel
η=0
Beam
x [crystal index]
Bottom
y [c
ryst
al in
dex
]
η=1.5
ϕη=-1.5
η=-
1.5
η=
-3.0
η=1
.5
η=
3.0
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 31
ECAL Preshower Responseto single Splash ’09 event
ECAL Preshower Responseto single Splash ’09 event
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
LV problem – 50% now fixed
Readout problem (now fixed)CMS 2009 Prelim.
η=-
1.65
η=
-2.6
η=1
.65
η=
2.6
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 32
NowNow
Preparing for the 2009/2010 Run
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 33
Ready for Collisions:Trigger Menu for 1031cm-2s-1
Ready for Collisions:Trigger Menu for 1031cm-2s-1
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 isolationPhotons:
• No isolation requirements at L1• Unprescaled at pT=25 GeV with no
isolationJets:
• Unprescaled 1-Jet pT=110 GeVMinBias:
• Algorithms use HF-tower ET,HF ET ring sums, Ecal ET, & pixel triplets
• 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
Higher Level Trig. Rates by Object
Planned HLT Rate 300 Hz(600 Hz capacity)<CPU time>/event = 42 ms(100 ms capacity)
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 34
Analysis Model in CMSAnalysis Model in CMS
Tier-1
Tier-2 Tier-2 Tier-2
Tier-3 Tier-3 Tier-3Tier-3
Tier-3
Tier-1 Computing Facilities are major repositories of MC & reconstructed data
Tier-2 Computing Facilities are half devoted to simulation half user analysis. Primary resource for analysis
Tier-3
CAF
Tier-3 Computing Facilities are entirely controlled by the providing institution & used for analysis
Tier-0CERN CAF
Tier-1 Tier-1Tier-2
Tier-2 Tier-1
Tier-3
CMS Analysis is performed on a globally distributed collection of computing facilities
Tier-2Tier-2
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 35
Computing ReadinessComputing ReadinessMC 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
October Exercise4 times average
Different colors for different Tier-2’sReady & Working
Not Ready
Scheduled Downtime
200k/day50 sites
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 36
Early Physics ProgramEarly Physics ProgramEarly 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 Wl (l = e,); 300 Zll (l =e, );
5 ttbar +X• Improved understanding of physics objects; jet energy scale
from W j j′; extensive use (& understanding) of b-tagging• Measure/understand backgrounds to SUSY & Higgs
searches• As data accumulates higher, look for excesses from SUSY
& Z′ resonances.
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 37
Particle Multiplicities &B physics
Particle Multiplicities &B physics
B+ → J/yK+ with 10 pb-1
B+ → J/yK+ with 10 pb-1
e.g. Exclusive B production with early data:• B+(0) → J/yK+(*0)
cross section & lifetime ratio for 10 pb-1 @ 10 TeV
Charged Hadron Multiplicity in Minimum Bias pp Collisions at 900 GeV and 10 TeV(5k events)
M J/yK+
900 GeV900 GeV
10 TeV10 TeV
10 TeV10 TeV
Analyses have beenredone for 7 TeV –available soon
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 38
QCD: Jet MeasurementsQCD: Jet Measurements
Startup inclusive jet measurement using kT & SISCone• Studying other algorithms – present intent to make anti-kT the default
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-1 data @ 10 TeV
Inclusive jet cross-section uncertainties (SISCone) for
10 pb-1 data @ 10 TeV
Inclusive jet cross-section measurement (kT) for 10 pb-1 data @ 10 TeV
Inclusive jet cross-section measurement (kT) for 10 pb-1 data @ 10 TeV
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 39
W, Z s∙BR (10 pb-1, 10 TeV)W, Z s∙BR (10 pb-1, 10 TeV)
syst. uncert: 2.4% + 10% for Ldt syst. uncert: 4.0% + 10% for Ldt;
Z eeZ ee W enW en
Z SelectionET > 20.0 GeVboth e isolated 70 < Me,e < 110 GeV
W SelectionET > 30.0 GeVIsolated e
Use data driven methods e.g. tag and probe method to work out efficiencies from “data”
W. Smith, U. Wisconsin, HCP, Nov. 16, 2009. CMS Detector Global Status - 40
Conclusions & OutlookConclusions & OutlookCMS 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!