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1J-C BRIENTPrague 2002Prague 2002
Performances studies of the calorimeter/muon det.
e+e– W+W– at s=800 GeV Simulation SLAC-Gismo
Simulation MOKKA-GEANT4Visualisation FANAL CALICECALICE
The paradigm in 2002 : the jet reconstruction is the key point
2J-C BRIENTPrague 2002Prague 2002
jet(s) or di-jet ?
zoom
e+e‒W+W– à s=800 GeV
Calorimeter jet view
View for W-Si ECAL and Digital HCAL
3J-C BRIENTPrague 2002Prague 2002
2 jet = 2ch. + 2 + 2 h0 ++ ++
dominant contributionsdominant contributions For a track momentum resolution about ~10-5 An ECAL energy resolution ~ 12% ( (stochastic term)An HCAL energy resolution ~ 45% ( (stochastic term)On a
2jet ~ (0.14)2 Ejet + 2
confusion + 2threshold
2confusion
The strategyThe strategyThe strategyThe strategy
Individual reconstruction of each particle by topology (Bubbles chamber)
The level of confusion between particle The level of confusion between particle determine the quality of the reconstructiondetermine the quality of the reconstruction
Impr
oper
ly c
alle
d E
nerg
y Fl
ow
EEjetjet = = Echarged track ++ E ++ Eh0
fraction fraction 65% 26% 9%
A typical jet
Large multiplicityof low/medium energy
particles
No confusionNo threshold ⇒∼0.14
2threshold
Adapted from
Dean K
arlen
4J-C BRIENTPrague 2002Prague 2002
The minimisation of the confusion contribution leads to ① A strong magnetic field and a large internal radius of the
calorimeter ⇨ Help for the separation charged /neutral
② A small Molière radius ⇨ Minimise the overlap between close showers
③ A maximisation of the longitudinal segmentation (vision in 3D)(vision in 3D)
⇨ Allows a better separation between close showers
④ to have both ECAL and HCAL inside the coil and minimise the dead zone
⑤ The development of 3D reconstruction algorithm
And for the threshold ⑥ A good S/N at low energy
Choice in ECFA groupsChoice in ECFA groups,, choice in LCD-US choice in LCD-US groupsgroupsACFA choice is differentACFA choice is different
e/h=1 and some precise layers
5J-C BRIENTPrague 2002Prague 2002
ECAL : Sampling tungsten-silicon
Sampling radiator-tile
HCAL : Sampling radiator-scintillator tiles
Sampling radiator-gas detector
n
CALICE CALICE W-Si Rint~170 Pad 1x1 cm
SD-LCD W-Si Rint~120 (SLAC-Oregon) Pad 0.5x0.5cm
LCCAL 5x5cm tiles (Italian labs) 3 silicon layers
ACFA choice 4x4cm tiles 2 layers fibers
Staggered tile Rint~160 (Uni. Colorado) tile 5x5cm
CALICE CALICE tile-HCALtile-HCAL projective tiles 9 layers
CALICE CALICE DHCAL ( Pad 1x1cm 1bit-readout
40 layers
And some exotic proposals (crystal ECAL,…)
6J-C BRIENTPrague 2002Prague 2002
CALICE CALICE performances performances studies includestudies include Performance variation with dead wafers, with inter-calibration(Only ECAL), with pad size (DHCAL), perf. on jets with HCAL resolution, with variation of X0 in tungsten plates,…
Electronics readout performances,noise,etc…is included (ECAL only)
Performance with jets (at Z peak for both HCAL option)
Performance with jets at high energy (numerical values for tile HCAL)
Studies of DHCAL performance (single track) with radiator (steel, tungsten,…) , with pad size.
Electron, muon ID. for isolated particle/in jets (better than ALEPH…)
TO DOTO DO Almost everything
- performances with pad size, with layer numbers (partly done for ECAL)- performances at high energy (including boson mass) - input for the electronics (HCAL mainly)- input for Lumi. measurement (end-cap), input for TPC T0 calibration.…………
7J-C BRIENTPrague 2002Prague 2002
Impact from dead wafersImpact from non-uniformity (inter-calibration)
Response non-uniformity in ECAL (%) Fraction of dead wafers in ECAL (%)
CALICECALICE ECAL studies
J-C. B. J-C. B.
Only a small variation of the performanceswith imperfect construction/knowledgeof the device
8J-C BRIENTPrague 2002Prague 2002
Photon ID in jets
Jets at 91 GeV
ZH at 500 GeVZ in , H in jets
Electron ID
Hadron MISID
Particle momentum GeV
ALL VALUES in %
Photon energy GeV
Electron ID in jets
ECAL
/mean ~ 29%/mean ~ 29%
DHCAL 1 cm
X 1
cm
DHCAL 1 cm
X 1
cm
HCAL
S.Magill
ID
Jet mass
→
→and→new
250 GeV ±
9J-C BRIENTPrague 2002Prague 2002
Jet mass < 0.2
Jet mass in 0.2-2
→
82% 17%
→
2% 90%
Tau decays ID is essential for ID and polarisation measurement
(250 GeV) →
charged pion
Photons from oLooking alongthe ch. trackin 5-12 X0
Looking along the charged track in the first 4 X0
10J-C BRIENTPrague 2002Prague 2002
CALICE ECAL(W-Si) + DHCAL
Z at rest decaying in jets
CALICECALICE ECAL+HCAL studies
D.Orlando
V.Morgunov
CALICE ECAL(W-Si) + THCAL
11J-C BRIENTPrague 2002Prague 2002
Position resolution ~2mm
SD-LCDSD-LCD (M.Iwasaki, T.Abe,…)
Photons ID in jets Effic. ~85% Purity ~ 85%
Top mass measurement (no neutral hadron rec.)
Resolution on photon directionEtc…
Need a more complete/improved reconstruction
LCCALLCCAL (P.Checchia)
Single particle perf. electron/pion separation electron position resolution
Need simulationNeed reconstruction
50 GeVElectron
Test beam data
10 GeV photon from IP
12J-C BRIENTPrague 2002Prague 2002
CALICECALICE A lot of performances have been estimated on GEANT3-4 simulation It remains a lot to do – progress foreseen for next ECFA workshop
LCCALLCCAL single particle performance in TB , jets ??
SD-LCDSD-LCD Works started with full simulation, some results on jets events
ST-ECALST-ECAL** Works in progress
ACFA ACFA calorimeter group Works in progress, single particle performance in TB
Conclusion
* Staggered tiles ECAL in Colorado
13J-C BRIENTPrague 2002Prague 2002
What about muon outer system
A la TDR (Marcello Picollo). Simulation Geant4 with only a crude reconstruction.
It clearly need to be linked with the inner detector (inside the coil) Which number of layers ? What is the best location in the Yoke,…Which mode (Streamer , avalanche) , which level of occupancy acceptable ?Which readout ? Which performance in jets ? , etc…
RPC’sRPC’s
Proposed by G.Fisk. Could be very cheap !! But so far I don’t know about any simulation and/or performances study.
Scintillator basedScintillator based “a la MINOS”
14J-C BRIENTPrague 2002Prague 2002
0
0.2
0.4
0.6
0.8
1
0 10 20 30 40 50
Muon momentum GeV
Effi
cien
cy m
uon
ID
Isolated muon ID. (crude criteria)
- with 2D readout 1x1 cm - from FULL simulation GEANT4
Marcello in Jeju-do
Note the threshold due to the coil atAbout 6 GeV/c