Cornell Seminar, Oct. 4, 2004 1 Physics at CMS Physics at CMS Status of CMS and US CMS Dan Green Fermilab October 6, 2004
Jan 31, 2016
Cornell Seminar, Oct. 4, 2004 1
Physics at CMSPhysics at CMSPhysics at CMSPhysics at CMS
Status of CMS
and
US CMS
Dan Green
Fermilab
October 6, 2004
Cornell Seminar, Oct. 4, 2004 2
OutlineOutlineOutlineOutline
• LHC Accelerator
• CMS Detector
• Trigger/DAQ - L1T, HLT
• Higgs• gg Fusion
• Associated Production, WW Fusion
• SUSY
• Exotica (Composites, Z’, Extra Dimensions, …)
• HI Program
Cornell Seminar, Oct. 4, 2004 3
LHC SignificanceLHC SignificanceLHC SignificanceLHC Significance
Higgs boson
t quark
b quark
s quark
ISR
Tevatron
SPEAR
SppS
TRISTAN
LEPII
CESR
Prin-Stan
Accelerators
electron
hadron
W, Z bosons
c quark
LHC
PEP
SLC
1960 1970 1980 1990 2000
Starting Year2010
10-1
100
101
102
103
104
Con
stit
uent
CM
Ene
rgy
(GeV
)
LHC will be the first big jump in C.M. energy and luminosity in 20 years. Based on the last 40 years of HEP, new phenomena are expected.
Cornell Seminar, Oct. 4, 2004 4
LHC ScheduleLHC ScheduleLHC ScheduleLHC Schedule
Blue is the planned schedule. Red is just in time. Issues of SC cable and cold masses (vendors) are solved. Testing at CERN is now the CP for dipoles – and cryoline installation. There is no reason to assume that the CERN schedule will not be ~ met. Three shift operation -> sector test in Spring 2006. Collisions in April 2007. Physics run (10 fb -1) starting in late 2007 ?.
Cornell Seminar, Oct. 4, 2004 5
The CMS DetectorThe CMS DetectorThe CMS DetectorThe CMS Detector
MUON BARREL
CALORIMETERS
ECAL
SUPERCONDUCTINGCOIL
IRON YOKE
TRACKER
MUONENDCAPS
HCAL
Basic Choices:
Strong, large B field (4T)
All Si tracking (L)
Best possible ECAL dE/E
Robust Muon - yoke
Cornell Seminar, Oct. 4, 2004 6
Magnet Coil : ~ 2/3 doneMagnet Coil : ~ 2/3 doneMagnet Coil : ~ 2/3 doneMagnet Coil : ~ 2/3 done
Expect the 5 modules at CERN by Nov., 2004 Start cooling in March 2005 Complete SX5 magnet test on Oct, 2005 Lower CMS into UX5 – 1.5 yr before LHC Lower CMS into UX5 – 1.5 yr before LHC beambeam
Cornell Seminar, Oct. 4, 2004 7
Trial Test of Coil InsertionTrial Test of Coil InsertionTrial Test of Coil InsertionTrial Test of Coil Insertion
Simulation ofcoil radial extent
Assembly of CMS proceeding in the surface hall (SX5).
Cornell Seminar, Oct. 4, 2004 8
CMS Tracker – All SiCMS Tracker – All SiCMS Tracker – All SiCMS Tracker – All Si
5.4 m
Outer Barrel –TOB-
Inner Barrel –TIB-
End cap –TEC-Pixel
2,4
m
Inner Disks –TID-
210 m2 of silicon sensors6,136 Thin detectors (1 sensor)9,096 Thick detectors (2 sensors)9,648,128 electronics channels
Cornell Seminar, Oct. 4, 2004 9
ECAL Test Beam ModuleECAL Test Beam ModuleECAL Test Beam ModuleECAL Test Beam Module
PbWO4 crystals. Fast and rad hard but light output is low APD. Electronics is IBM 0.25 um which is radiation hard.
Cornell Seminar, Oct. 4, 2004 10
HCAL : HB and HEHCAL : HB and HEHCAL : HB and HEHCAL : HB and HE
Back-flange18 Brackets3 Layers of absorber
Scintillator + brass. Use HPD and QIE.
Cornell Seminar, Oct. 4, 2004 11
Endcap Muon ChambersEndcap Muon ChambersEndcap Muon ChambersEndcap Muon Chambers
Endcap return yoke and CSC
Cornell Seminar, Oct. 4, 2004 12
Detector Performance/StatusDetector Performance/StatusDetector Performance/StatusDetector Performance/Status
• TTC vetted, 25 nsec test beam in 2003, ESR passed, 0.25 m commonality, GOL standard.
• Pixels – occupancy ~0.0001, impact ~ 15 m, R&D. production in 2005.
• SiTrkr – pre-production, dpT/pT~0.02 at 100 GeV. Full production in 2005.
• Calor – production, timing with laser, calib with construction data. Testbeam G4 data set, cosmic muons. Minbias, Z -> ee, t -> Wb, J-J and J - in situ.
• Muons – production, slice tests, alignment, trigger primitives on cosmic muons.
Cornell Seminar, Oct. 4, 2004 13
DAQ TDR: Level-1 TriggerDAQ TDR: Level-1 TriggerDAQ TDR: Level-1 TriggerDAQ TDR: Level-1 Trigger
Information from calorimeters
and muon detectors• Electron/photon triggers
• Jet and missing ET triggers
• Muon triggers
High efficiency for discovery level Physics with ~ 30 kHz bandwidth (~ 3x headroom)
Cornell Seminar, Oct. 4, 2004 14
Level-1 Trigger Table (10Level-1 Trigger Table (103434))Level-1 Trigger Table (10Level-1 Trigger Table (103434))
Trigger Threshold
(GeV or GeV/c)
Rate (kHz) Cumulative Rate (kHz)
Isolated e/ 34 6.5 6.5
Di-e/ 19 3.3 9.4
Isolated muon 20 6.2 15.6
Di-muon 5 1.7 17.3
Single tau-jet 101 5.3 22.6
Di-tau-jet 67 3.6 25.0
1-jet, 3-jet, 4-jet 250, 110, 95 3.0 26.7
Jet*ETmiss 113*70 4.5 30.4
Electron*jet 25*52 1.3 31.7
Muon*jet 15*40 0.8 32.5
Min-bias 1.0 33.5
TOTAL 33.5
L1 Trigger on leptons, jets, missing ET and calib/minbias
Cornell Seminar, Oct. 4, 2004 15
Minimum Bias EventsMinimum Bias Events Minimum Bias EventsMinimum Bias Events
• Pileup must be understood in dealing with Physics.
• Isolation criteria are applied and efficiency must be understood.
• A fast calibration to reduce the number of calorimeter constants
• Use symmetry of deposited energy to inter-calibrate calorimeter towers within rings of constant
BarrelCMS Note 2003-031
D.F
ut y
an ,
C.S
ee
z
Cornell Seminar, Oct. 4, 2004 16
DAQ TDR: DAQ DAQ TDR: DAQ DAQ TDR: DAQ DAQ TDR: DAQ
• Event size: 1MB from ~700 front-end electronics modules
• Level-1 decision time: ~3s — ~1s actual processing(the rest in transmission delays)
• DAQ designed to accept Level-1 rate of 100kHz
• Modular DAQ: 8 x 12.5kHz units
• HLT designed to output O(102)Hz – rejection of 1000
• DAQ factorizes by 8x
Cornell Seminar, Oct. 4, 2004 17
HLT Selection - HLT Selection - HLT Selection - HLT Selection -
-leptons• Level-2:
calorimetric reconstruction and isolation
• Very narrow jet surrounded by isolation cone
• Level-3: tracker isolation
Cornell Seminar, Oct. 4, 2004 18
HLT Electron Selection: Level-2HLT Electron Selection: Level-2HLT Electron Selection: Level-2HLT Electron Selection: Level-2
“Level-2” electron:
• Search for match to Level-1 trigger
• Use 1-tower margin around 4x4-tower trigger region
• Bremsstrahlung recovery “super-clustering”
• Select highest ET cluster
Brem recovery:
• Road along in narrow -window around seed
• Collect all sub-clusters in road “super-cluster”
basic cluster
super-cluster
Cornell Seminar, Oct. 4, 2004 19
HLT Electron Selection: Level-2.5HLT Electron Selection: Level-2.5HLT Electron Selection: Level-2.5HLT Electron Selection: Level-2.5
Most e triggers are neutrals use pixel information
• Very fast, large rejection with high efficiency
• Before most material before most bremsstrahlung, and before most conversions
• Number of potential hits is 3, so demanding 2 hits is quite efficient
Full pixel system
Staged option
Cornell Seminar, Oct. 4, 2004 20
HLT and Physics EfficiencyHLT and Physics EfficiencyHLT and Physics EfficiencyHLT and Physics Efficiency
Cornell Seminar, Oct. 4, 2004 21
HLT Performance HLT Performance — Efficiency— EfficiencyHLT Performance HLT Performance — Efficiency— Efficiency
Channel Efficiency
(for fiducial objects)
H(115 GeV) 77%
H(160 GeV)WW* 2 92%
H(150 GeV)ZZ4 98%
A/H(200 GeV)2 45%
SUSY (~0.5 TeV sparticles) ~60%
With RP-violation ~20%
We 67% (||<2.1, 60%)
W 69% (||<2.1, 50%)
tX 72%
Cornell Seminar, Oct. 4, 2004 22
Preparing for PhysicsPreparing for PhysicsPreparing for PhysicsPreparing for Physics
To do the Physics well, we must – by 2007:
• Commission – SX5, slice tests, trigger primitives, portable DAQ, pulsers, lasers, cosmics
• Calibrate – test beam, sources, lasers, muons
• Align – muons, photogrammetry, proximity sensors
• Deploy Core Software – data challenges, calib samples (W, Z, JJ, J, minbias)
Cornell Seminar, Oct. 4, 2004 23
SWC ChallengesSWC ChallengesSWC ChallengesSWC Challenges
Cornell Seminar, Oct. 4, 2004 24
Physics TDR goalsPhysics TDR goalsPhysics TDR goalsPhysics TDR goals
Physics TDR is a test of validity/readiness of CMS to extract initial Physics
• Readiness of software, computing and people’s knowledge, skills
• Next step is the Physics TDR so that
It is:
• an opportunity to write, debug, clean, re-write our software
• a test/chance to tune data-handling and distributed analysis
• re-evaluate our (detector/software) strengths and weaknesses
• the way to identify priorities at T0, plus general time-scales
• e.g. SUSY shows up quickly
• a way to learn the new system (start in late 2003, end in 2005)
• Necessary input to major computing procurements in 2006.
Cornell Seminar, Oct. 4, 2004 25
Higgs ProductionHiggs ProductionHiggs ProductionHiggs Production
Cornell Seminar, Oct. 4, 2004 26
Higgs Decay ModesHiggs Decay ModesHiggs Decay ModesHiggs Decay Modes
Goal is to measure mass, total width and several partial widths to confront the SM incisively. At low mass, several couplings are measurable. At higher masses WW and ZZ dominate.
Cornell Seminar, Oct. 4, 2004 27
““Higgs” Quantum NumbersHiggs” Quantum Numbers““Higgs” Quantum NumbersHiggs” Quantum Numbers
•If the 2 photon mode is observed then “H” is not a vector (Yangs’ theorem).
•If the “H” is the SM Higgs then the leptons are ~ collinear in a WW decay.
•If the ZZ decay is seen then a P = + state has decay planes aligned – P = - has planes orthogonal .
1 2x 1 2
Cornell Seminar, Oct. 4, 2004 28
Associated Production - HttAssociated Production - HttAssociated Production - HttAssociated Production - Htt
H is radiated in a tt final state. At low H mass the cross section is sufficient to extract a clean signal in the dominant H -> bb decay mode. In addition, a “control” sample arises from the ttZ state with a leptonic Z decay (same Feynman diagrams).
Cornell Seminar, Oct. 4, 2004 29
Htt Associated ProductionHtt Associated ProductionHtt Associated ProductionHtt Associated Production
Good b tagging is clearly essential.
ttZ can be used to measure the background in bb using leptonic Z decays.
Most background processes have large scale uncertainties.
Cornell Seminar, Oct. 4, 2004 30
H Production from W+WH Production from W+WH Production from W+WH Production from W+W
Use the EW radiation of a W by a quark. The “effective W approximation” analogous to the WW approximation. Need good jet coverage to low PT and small angles. Cross section depends only on the Higgs coupling to W, Z.
Cornell Seminar, Oct. 4, 2004 31
qqH,H -> W+W* -> qqH,H -> W+W* -> qqH,H -> W+W* -> qqH,H -> W+W* ->
SM H leads to ~ collinear and low mass lepton pairs. qqH is most useful for H masses > 140 GeV.
Cornell Seminar, Oct. 4, 2004 32
Higgs Summary in CMSHiggs Summary in CMSHiggs Summary in CMSHiggs Summary in CMS
For 10 fb-1, or 1 year at 1/10 of design luminosity almost all the allowed range for a SM Higgs is covered.
CMS must be ready to quickly and incisively analyze the early LHC data.
qqW, WW*, ZZ* are the discovery modes at low mass.
Cornell Seminar, Oct. 4, 2004 33
Higgs Self Coupling Higgs Self Coupling Higgs Self Coupling Higgs Self Coupling
Baur, Plehn, Rainwater HH W+ W- W+ W- jj jj
Find the Higgs? If the H mass is known, then the SM H potential is completely known HH prediction. If H is found, measure self-couplings, but ultimately SLHC is needed. The plan is for 10x increase in luminosity ~ 2013.
Cornell Seminar, Oct. 4, 2004 34
WW Fusion into ZZWW Fusion into ZZWW Fusion into ZZWW Fusion into ZZ
No Higgs? Look at VV scattering. Process depends only on VVV, VVVV couplings. Not viable at Tevatron. In SM cross section -> a constant, angular distribution is F/B peaked, and WLWL flux dominates. If no H then possibly large enhancement due to TT scattering.
Cornell Seminar, Oct. 4, 2004 35
W+W -> Z + Z Angular DistributionW+W -> Z + Z Angular DistributionW+W -> Z + Z Angular DistributionW+W -> Z + Z Angular Distribution
If there is a SM H then the distribution is very F/B peaked. If not, then the cross section may have a dramatic (~ 80 x) increase and the angular distribution may become isotropic – e.g. pure quartic. Need SLHC to push to ZZ masses > 1 TeV.
Cornell Seminar, Oct. 4, 2004 36
SUSY ?SUSY ?SUSY ?SUSY ?
Why SUSY?
•GUT Mass scale, unification
•Improved Weinberg angle prediction
•p decay rate
•Neutrino mass (seesaw)
•Mass hierarchy – Planck/EW
•String connectionsMMSM has ~ SM light h and ~ mass degenerate H,A. LSP is neutralino. Squarks and gluinos are heavy.
Cornell Seminar, Oct. 4, 2004 37
WMAP and Other ConstraintsWMAP and Other ConstraintsWMAP and Other ConstraintsWMAP and Other Constraints
LEP2
g-2
WMAP
LSP is neutral
b s
Cornell Seminar, Oct. 4, 2004 38
SUSY Cross Sections at LHCSUSY Cross Sections at LHCSUSY Cross Sections at LHCSUSY Cross Sections at LHC
Squarks and gluinos are most copious (strong production). Cascade decay to LSP ( ) study jets and missing energy. E.g. 600 GeV squark. Dramatic event signatures and large cross section mean we will discover SUSY quickly, if it exists.
01
Cornell Seminar, Oct. 4, 2004 39
SUSY – Mass “Reach”SUSY – Mass “Reach”SUSY – Mass “Reach”SUSY – Mass “Reach”
WMAP
1 year at 1/10 design luminosity.
SUSY discovery would happen quickly.
Cornell Seminar, Oct. 4, 2004 40
SUSY – Mass ScaleSUSY – Mass Scale SUSY – Mass ScaleSUSY – Mass Scale
Effective mass “tracks”squark/gluino mass well
4
1
( ) ( jets)eff T TM P P
1 year at l/10th design luminosity
Will immediately start to measure the fundamental SUSY parameters.
With 4 jets + missing energy the SUSY mass scale can be established to 20 %.
Cornell Seminar, Oct. 4, 2004 41
Sparticle CascadesSparticle CascadesSparticle CascadesSparticle Cascades
Use SUSY cascades to the stable LSP to sort out the new spectroscopy.
Decay chain used is :
Then
And
Final state is
02
02b b
g b b
1o
01b b
Cornell Seminar, Oct. 4, 2004 42
Sparticle MassesSparticle MassesSparticle MassesSparticle Masses
2-body decay: edge in Mll
10 fb-1
An example of the kind of analysis done, from 1 year at 1/10th design luminosity.
Cornell Seminar, Oct. 4, 2004 43
Full CMS Exposure – Full CMS Exposure – Reconstruction of Heavy StatesReconstruction of Heavy States
Full CMS Exposure – Full CMS Exposure – Reconstruction of Heavy StatesReconstruction of Heavy States
0 02 1 2
ob b g b b
Cornell Seminar, Oct. 4, 2004 44
SUSY Higgs must be light, < 130 GeV
Signature: B-jets + lepton + ETmiss
Requires b-tagging + jet counting + full calorimeter coverage for ET
miss
h Decays to b pairsh Decays to b pairsh Decays to b pairsh Decays to b pairs
Cornell Seminar, Oct. 4, 2004 45
A to A to + + to Leptons to LeptonsA to A to + + to Leptons to Leptons
Fast simulations of b and tau tags. Tau decays to leptons. Background from Z, tt, Wtb
Cornell Seminar, Oct. 4, 2004 46
A,H to A,H to + + to Hadrons to HadronsA,H to A,H to + + to Hadrons to Hadrons
Even in the minimal model, there is a large parameter space. This study uses hadronic tau decays. A and H are nearly mass degenerate.
Cornell Seminar, Oct. 4, 2004 47
HH++-> t + b-> t + bHH++-> t + b-> t + b
Charged Higgs decay into quarks. Top decays to W+b with W decay to leptons supplying the trigger. H couples preferentially to high mass t quark.
Cornell Seminar, Oct. 4, 2004 48
Heavy SUSY Higgs - 10 fbHeavy SUSY Higgs - 10 fb-1-1 Heavy SUSY Higgs - 10 fbHeavy SUSY Higgs - 10 fb-1-1
A / H tan =30, mA=130 GeV
A / H tan =40, mA=200 GeV
Some parts of the parameter space are not covered using dilepton decays of H,A.
Cornell Seminar, Oct. 4, 2004 49
is the jet-jet C.M.scattering angle.If contact interactions excess at low , S wave scattering . Reach of CMS is ~ 20 TeV. CanPush up with SLHC.
No Higgs? No SUSY? Weak interactions will become strong.2-jet events: expect excess of high-ET centrally produced jets if quarks are composites (a la Rutherford).
Composites - JetsComposites - JetsComposites - JetsComposites - Jets
ˆ ˆ(1 cos ) /(1 cos )
Cornell Seminar, Oct. 4, 2004 50
Early Physics Reach – q*Early Physics Reach – q*Early Physics Reach – q*Early Physics Reach – q*
If the calorimetry is understood, resonances up to a few TeV in mass are accessible early in the LHC run. (R. Harris) SLHC gives ~ 20% increase in mass reach.
Cornell Seminar, Oct. 4, 2004 51
Composites - DYComposites - DYComposites - DYComposites - DY
Search for lepton composites in D-Y production of dilepton pairs. At masses above the Z there is no known resonant state. Reach is ~ 20 TeV. Early reach is ~ 5 TeV for 10 fb-1.
Cornell Seminar, Oct. 4, 2004 52
Extra DimensionsExtra DimensionsExtra DimensionsExtra Dimensions
Number (D) of space-time dimensions form of force observed• E+M: F~1/r2 because D=3+1
• For “flatlanders” confined to live in D=2+1 dimensions, E+M is perceived to be a F~1/r force
Inspired by “string theory” which naturally incorporates SUSY and which requires extra dimensions to be self consistent. The extra dimensions required by strings may be at the Plank scale or at the TeV scale, In the latter case there is no hierarchy problem.
Cornell Seminar, Oct. 4, 2004 53
TeV Scale Extra Dimension TeV Scale Extra Dimension TeV Scale Extra Dimension TeV Scale Extra Dimension
KK excitations of the , Z in D-Y LHC at 600 fb-1 has a reach to 6 TeV. SLHC would push out 30% further.
Black hole production Democratic Hawking evaporation copious Higgs production. Study with full CMS simulation.
Cornell Seminar, Oct. 4, 2004 54
Black Hole Production at CMSBlack Hole Production at CMSBlack Hole Production at CMSBlack Hole Production at CMS
If the extra dimensions are ~ If the extra dimensions are ~ TeV scale, then black holes TeV scale, then black holes should be produced at the should be produced at the LHC. LHC. Black holes decay immediately ( ~ 10-26 s) by Hawking radiation (democratic evaporation) :large multiplicity, small missing E, jets/leptons ~ 5.
A black hole event with MBH ~ 8 TeV
Spectacular signature !
Cornell Seminar, Oct. 4, 2004 55
Heavy Ion Physics in CMSHeavy Ion Physics in CMSHeavy Ion Physics in CMSHeavy Ion Physics in CMS
Study properties of hot nuclear matter, plasma of quarks and gluons• Use high pT jets and quarkonia as probes of the medium
• Jet quenching, a new QCD process
• Production and survival of quarkonia: J/ ,• Study as a function of nuclear geometry
Compare to p+p: minimum bias physics at the start of LHC
q
q
q
q
p+p Ion+Ion
Cornell Seminar, Oct. 4, 2004 56
HI Measurements in CMSHI Measurements in CMSHI Measurements in CMSHI Measurements in CMS
Excellent detector for high pT probes:
• High rates and large cross sections
• quarkonia (J/ ,) and heavy quarks (bb)
• high pT jets, including detailed studies of jet fragmentation
• high energy photons, Z0
• Correlations
• jet-• jet-Z0
• multijets
Global event characterization
• Energy flow in wide rapidity range
• Charged particle multiplicity
• Centrality
CMS can use highest luminosities available at LHC both in A+A and p+A modes
• DAQ and Trigger uniquely suited to dual-mode experimentation
-
Cornell Seminar, Oct. 4, 2004 57
Jet Quenching at RHICJet Quenching at RHICJet Quenching at RHICJet Quenching at RHIC
STAR
CMS
Cornell Seminar, Oct. 4, 2004 58
Summary and ConclusionsSummary and ConclusionsSummary and ConclusionsSummary and Conclusions
• CMS is designed for discovery• Trigger strategy is sound (e.g. no L2)• Higgs is ~ assured of discovery if it
exists.• SUSY is ~ assured if it exists as a
solution of the Hierarchy Problem.• Discoveries will come early because
energy matters. CMS must be ready on day one. Next step is the Physics TDR.
• With the SLHC the program at CMS will span decades.
Cornell Seminar, Oct. 4, 2004 59
CMS Tracking - CrossingCMS Tracking - CrossingCMS Tracking - CrossingCMS Tracking - Crossing
Cornell Seminar, Oct. 4, 2004 61
ECAL – PbWO CrystalsECAL – PbWO CrystalsECAL – PbWO CrystalsECAL – PbWO Crystals
Fully active detector – transverse size ~ Xo
Cornell Seminar, Oct. 4, 2004 62
CMS ECAL CalibrationCMS ECAL Calibration CMS ECAL CalibrationCMS ECAL Calibration
1. Lab measurements of all modules; light yield, APD gain etc. 4.5 %
2. Testbeam precalibration transported to CMS (for 25% of detector) 2.0 %
• Distributed within detector, as “standard candle”
3. Min-bias phi symmetry 2 %
• Fast calibration to reduce number of calibration constants
4. Z e+e- 0.5 % (design value)
• Needs tracking in Si-tracker• Within ~2 months
5. Laser monitoring system over time to monitor crystal transparency
APDs
Total ~85,000 channels
Cornell Seminar, Oct. 4, 2004 63
225 GeV muon
beam
beam
100 GeV electron
AD
C c
ount
s
beam
300 GeV pion
HCAL 2002 Test BeamHCAL 2002 Test BeamHCAL 2002 Test BeamHCAL 2002 Test Beam
Cornell Seminar, Oct. 4, 2004 64
Measurement of HO muon signal for RPC trigger (Goal: use the HO as part of muon trigger)
beamHO
HO SignalPedestal Subtracted
Pedestal Distribution
HO in 2002 Test BeamHO in 2002 Test BeamHO in 2002 Test BeamHO in 2002 Test Beam
Cornell Seminar, Oct. 4, 2004 65
Resolution Linearity
Check Monte Carlo – G4Check Monte Carlo – G4Check Monte Carlo – G4Check Monte Carlo – G4
Cornell Seminar, Oct. 4, 2004 66
Muon System – 4 StationsMuon System – 4 StationsMuon System – 4 StationsMuon System – 4 Stations
HO
Cornell Seminar, Oct. 4, 2004 67
Muon Performance - BMuon Performance - BssMuon Performance - BMuon Performance - Bss
Lvl-1 Lvl-1 HLT HLT Global Global Events/ 10fbEvents/ 10fb-1-1 Trigger RateTrigger Rate
15.2%15.2% 33.5%33.5% 5.1%5.1% 4747 <1.7Hz<1.7Hz
Offline analysis results (hep-ph/9907256), using SM BR=3.5x10-9
(Lvl-1 trigger in ||<2.4 instead of ||< 2.1)10 fb-1 => 7 signal events with <1 background
5 observation with 30 fb-1
= 46 MeV= 46 MeV
Cornell Seminar, Oct. 4, 2004 68
Level-1 Trigger Table (2x10Level-1 Trigger Table (2x103333))Level-1 Trigger Table (2x10Level-1 Trigger Table (2x103333))
Trigger Threshold
(GeV)
Rate (kHz) Cumulative Rate (kHz)
Isolated e/ 29 3.3 3.3
Di-e/ 17 1.3 4.3
Isolated muon 14 2.7 7.0
Di-muon 3 0.9 7.9
Single tau-jet 86 2.2 10.1
Di-tau-jet 59 1.0 10.9
1-jet, 3-jet, 4-jet 177, 86, 70 3.0 12.5
Jet*ETmiss 88*46 2.3 14.3
Electron*jet 21*45 0.8 15.1
Min-bias 0.9 16.0
TOTAL 16.0
Cornell Seminar, Oct. 4, 2004 69
HLT Summary: 2x10HLT Summary: 2x103333 cm cm-2-2ss-1-1HLT Summary: 2x10HLT Summary: 2x103333 cm cm-2-2ss-1-1
Trigger Threshold(GeV or GeV/c)
Rate (Hz) Cuml. rate (Hz)
Inclusive electron 29 33 33
Di-electron 17 1 34
Inclusive photon 80 4 38
Di-photon 40, 25 5 43
Inclusive muon 19 25 68
Di-muon 7 4 72
Inclusive tau-jet 86 3 75
Di-tau-jet 59 1 76
1-jet * ETmiss 180 * 123 5 81
1-jet OR 3-jet OR 4-jet
657, 247, 113 9 89
Electron * jet 19 * 45 2 90
Inclusive b-jet 237 5 95
Calibration etc 10 105
TOTAL 105
Cornell Seminar, Oct. 4, 2004 70
B Tagging EfficiencyB Tagging EfficiencyB Tagging EfficiencyB Tagging Efficiency
The actual light quark rejection and b quark acceptance as a function of ET will only be known when the actual environment and performance of the tracker is known.
Cornell Seminar, Oct. 4, 2004 71
Standard Model PhysicsStandard Model PhysicsStandard Model PhysicsStandard Model Physics
Yields Cross section(nb)
Acceptance (1 in <2.1)
Eff. after HLT with isolation
Yield for 10
fb-1
W 19.6 50 % 69 % 7 × 107
Z 1.84 71 % 92 % 1.1 × 107
tt WbWb +X 0.126 86 % 72 % 7.8 ×
105
• rare top decays
• precision measurements of top couplings and properties
• EW boson triple gauge couplings
An example: standard model physics using muons, CMS
Cornell Seminar, Oct. 4, 2004 72
Muon Trigger EfficienciesMuon Trigger EfficienciesMuon Trigger EfficienciesMuon Trigger Efficiencies
Cornell Seminar, Oct. 4, 2004 73
Higgs Mass – Low?Higgs Mass – Low?Higgs Mass – Low?Higgs Mass – Low?
102
103
10-3
10-2
10-1
100
101
102
103 Higgs Width
MH
(GeV)
H
(Ge
V)
Current EW data indicates a low mass H. SUSY requires a low mass H. The mass width is then likely to be small < experimental resolution ECAL
Cornell Seminar, Oct. 4, 2004 74
Low Mass Higgs Low Mass Higgs Low Mass Higgs Low Mass Higgs
H: decay is rare (B~10-3)• But with good resolution, one gets a mass
peak
• Motivation for PbWO4
calorimeter
• CMS: at 100 GeV, 1GeV
• S/B 1:20
Cornell Seminar, Oct. 4, 2004 75
Intermediate Mass HiggsIntermediate Mass HiggsIntermediate Mass HiggsIntermediate Mass Higgs
HZZ+–+– ( =e,)• Very clean
• Resolution: better than 1 GeV (around 100 GeV mass)
• Valid for the mass range 130<MH<600 GeV/c2
Cornell Seminar, Oct. 4, 2004 76
H -> Z + Z* -> 4H -> Z + Z* -> 4H -> Z + Z* -> 4H -> Z + Z* -> 4
V. Bartsch et al., Karlsruhe
Cornell Seminar, Oct. 4, 2004 77
H -> Z + Z -> 4 H -> Z + Z -> 4 H -> Z + Z -> 4 H -> Z + Z -> 4
Expected invariant mass distribution for L = 20 fb-1,
after selection. M. Sani et al., Firenze
Cornell Seminar, Oct. 4, 2004 78
High Mass HiggsHigh Mass HiggsHigh Mass HiggsHigh Mass Higgs
HZZ +–jet jet• Need higher Branching
fraction (also for the highest masses ~ 800 GeV/c2)
• At the limit of statistics
Cornell Seminar, Oct. 4, 2004 79
No Higgs? VV Scattering?No Higgs? VV Scattering?No Higgs? VV Scattering?No Higgs? VV Scattering?
If no Higgs look at VV scattering? Individual diagrams diverge with C.M. energy. Total set of 3 EW diagrams approaches a constant. The ~ isotropic distribution of each diagram becomes a F/B peak in the sum of the 3 EW diagrams.
Cornell Seminar, Oct. 4, 2004 80
SUSY and Grand UnificationSUSY and Grand UnificationSUSY and Grand UnificationSUSY and Grand Unification
Cornell Seminar, Oct. 4, 2004 81
Minimal SUSYMinimal SUSYMinimal SUSYMinimal SUSY
2 vev (ratio tan sign ) 2 masses (at GUT scale), soft SUSY breaking. Leads to 5 Higgs, sleptons, gauginos (LSP) and squarks and gluinos (higher mass0
Cornell Seminar, Oct. 4, 2004 82
SUSY Mass ReachSUSY Mass ReachSUSY Mass ReachSUSY Mass Reach
Cornell Seminar, Oct. 4, 2004 83
Supersymmetry Supersymmetry Supersymmetry Supersymmetry
CMS
tan=10
5 contours
Impact of the SLHCExtending the discovery regionby roughly 0.5 TeV i.e. from ~2.5 TeV 3 TeV
This extension involved highET jets/leptons and missing ET
Not compromised by increased pile-up at SLHC
Cornell Seminar, Oct. 4, 2004 84
SUSY - DisoverySUSY - DisoverySUSY - DisoverySUSY - Disovery
4
1
( ) ( jets)eff T TM P P
backgrounds
SUSY600 GeV
squark
Dramatic event signatures and large cross section mean we will discover SUSY quickly, if it exists.
Cornell Seminar, Oct. 4, 2004 85
Sparticle Mass MeasurementsSparticle Mass MeasurementsSparticle Mass MeasurementsSparticle Mass Measurements
Proposed Post-LEP Benchmarks for Supersymmetry (hep-ph/0106204)Proposed Post-LEP Benchmarks for Supersymmetry (hep-ph/0106204)
Cornell Seminar, Oct. 4, 2004 86
A, H to A, H to + + A, H to A, H to + +
A and H are ~ mass degenerate. B tag useful for backgrounds.
Cornell Seminar, Oct. 4, 2004 87
HH++ -> -> ++ + + HH++ -> -> ++ + +
Cornell Seminar, Oct. 4, 2004 88
Sparticle Reconstruction Sparticle Reconstruction Sparticle Reconstruction Sparticle Reconstruction
Cornell Seminar, Oct. 4, 2004 89
Sparticle ReconstructionSparticle ReconstructionSparticle ReconstructionSparticle Reconstruction
Cornell Seminar, Oct. 4, 2004 90
SUSY HiggsSUSY HiggsSUSY HiggsSUSY Higgs
Mass of h = mass of Z. With top loops the h mass is increased. However, mass of h is < 130 GeV. Thus, SUSY predicts a light “Higgs” ~ the SM Higgs.
Cornell Seminar, Oct. 4, 2004 91
Timing of Physics TDRTiming of Physics TDRTiming of Physics TDRTiming of Physics TDR
Physics TDR: start in 2003, end in 2005
Time scale determined by:• Desire to submit as late as possible
• To cover all software; to supplement it with real-life examples of prime physics analyses (training ground/ test of analysis chain).
• In 2006 we start procurements of major parts of the computing resources of the experiment
• And it’s the last point in time to make any major changes to the software infrastructure
• “T01.5”: near-optimal time to have this “test of Physics readiness”
Cornell Seminar, Oct. 4, 2004 92
CPT OrganizationCPT OrganizationCPT OrganizationCPT Organization
ECAL/e/C. Seez
HiggsS. Nikitenko
TRACKER/b-M.Mannelli,L.Silvestris
SUSY & Beyond SM
L. Pape
HCAL/JetMETJ.Rohlf,C.Tully
Standard Model
J. Mnich
MuonsD. Acosta,
U.Gasparini
Heavy IonsB. Wyslouch
Resource ManagerI. Willers
Technical Coordinator
L. Taylor
Arch, Frmwrks &
ToolkitsV. Innocente
Regional Centers
L. Bauerdick
Librarian ServicesS. Ashby
Production & data mgmt
T. Wildish
GRID Integration
C. Grandi
Computing infrastructure
N. Sinanis
Online Farm
Online Filter Software
CCS PM D. Stickland
PRS PM P. Sphicas
TRIDAS (Onl. Farm)
PM S. Cittolin
CPT Institution Board
Reconstruction project S. Wynhoff
Simulation project A. DeRoeck