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Performances studies of the calorimeter/muon det. e + e – W + W – at s=800 GeV. Simulation SLAC-Gismo. Simulation MOKKA-GEANT4 Visualisation FANAL. CALICE. The paradigm in 2002 : the jet reconstruction is the key point. jet(s) or di-jet ?. View for W-Si ECAL and Digital HCAL.
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Performances studies of the calorimeter/muon det. e+e–W+W–at s=800 GeV Simulation SLAC-Gismo SimulationMOKKA-GEANT4 Visualisation FANAL CALICE The paradigm in 2002: the jet reconstruction is the key point
jet(s) or di-jet ? View for W-Si ECAL and Digital HCAL e+e‒W+W– à s=800 GeV zoom Calorimeter jet view
Ejet =Echarged track+E+Eh0 fraction 65%26%9% A typical jet Large multiplicity of low/medium energy particles The strategy Individual reconstruction of each particle by topology(Bubbles chamber) Improperly called Energy Flow 2 jet =2ch. +2 +2 h0++ 2confusion 2threshold Adapted from Dean Karlen dominant 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 + 2confusion + 2threshold No confusion No threshold ⇒∼0.14 The level of confusion between particle determine the quality of the reconstruction
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) ⇨Allows a better separation between close showers ④to have both ECAL and HCAL inside the coil and minimise the dead zone ⑤The development of 3D reconstruction algorithm And for the threshold ⑥A good S/N at low energy Choice in ECFA groups,choice in LCD-US groups ACFA choice is different e/h=1 and some precise layers
CALICE W-Si Rint~170 Pad 1x1 cm SD-LCD W-Si Rint~120 (SLAC-Oregon) Pad 0.5x0.5cm ECAL :Sampling tungsten-silicon Sampling radiator-tile HCAL : Sampling radiator-scintillator tiles Sampling radiator-gas detector n LCCAL 5x5cm tiles (Italian labs)3 silicon layers ACFA choice 4x4cm tiles 2 layers fibers Staggered tile Rint~160 (Uni. Colorado) tile 5x5cm CALICE tile-HCALprojective tiles 9 layers CALICE DHCAL ( Pad 1x1cm 1bit-readout 40 layers And some exotic proposals (crystal ECAL,…)
CALICE performances studies 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 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. …………
CALICEECAL studies Impact from non-uniformity (inter-calibration) Impact from dead wafers J-C. B. J-C. B. Fraction of dead wafers in ECAL (%) Response non-uniformity in ECAL (%) Only a small variation of the performances with imperfect construction/knowledge of the device
Electron ID in jets Photon ID in jets ALL VALUES in % E CAL ZH at 500 GeV Z in , H in jets Jets at 91 GeV Hadron MISID Electron ID Particle momentum GeV Photon energy GeV H CAL 250 GeV ± S.Magill /mean ~ 29% ID → new • → and • → DHCAL 1 cm X 1 cm Jet mass
Tau decays ID is essential for ID and polarisation measurement (250 GeV)→ Looking along the charged track in the first 4 X0 charged pion Photons from o Looking along the ch. track in 5-12 X0
CALICEECAL+HCAL studies CALICEECAL(W-Si)+ DHCAL D.Orlando Z at rest decaying in jets CALICEECAL(W-Si)+ THCAL V.Morgunov
LCCAL(P.Checchia) Single particle perf. electron/pion separation electron position resolution Need simulation Need reconstruction Position resolution ~2mm 50 GeV Electron Test beam data 10 GeV photon from IP SD-LCD(M.Iwasaki, T.Abe,…) Photons ID in jets Effic. ~85% Purity ~ 85% Top mass measurement(no neutral hadron rec.) Resolution on photon direction Etc… Need a more complete/improved reconstruction
Conclusion CALICEA lot of performances have been estimated on GEANT3-4 simulation It remains a lot to do – progress foreseen for next ECFA workshop LCCALsingle particle performance in TB , jets ?? SD-LCDWorks started with full simulation, some results on jets events ST-ECAL*Works in progress ACFA calorimeter groupWorks in progress, single particle performance in TB *Staggered tiles ECAL in Colorado
What about muon outer system RPC’s 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… “a la MINOS” Scintillator based Proposed by G.Fisk. Could be very cheap !! But so far I don’t know about any simulation and/or performances study.
1 Marcello in Jeju-do 0.8 Isolated muon ID. (crude criteria) - with 2D readout 1x1 cm - from FULL simulation GEANT4 Note the threshold due to the coil at About 6 GeV/c Efficiency muon ID 0.6 0.4 0.2 0 0 10 20 30 40 50 Muon momentum GeV