Документ взят из кэша поисковой машины. Адрес оригинального документа : http://zebu.uoregon.edu/~uochep/talks/talks02/LC-detectors-2.pdf Дата изменения: Fri Mar 14 01:56:35 2003 Дата индексирования: Tue Oct 2 12:05:51 2012 Кодировка: Поисковые слова: asteroid

Vertex Detector
same VXD inside all three detectors (L, SD, and P) 670,000,000 pixels [20x20x20 (µm)3] 3 µm hit resolution inner radius = 1.2 cm 5 layer stand-alone tracking

Cos = 0.98

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Impact Parameter Resolution

dR (cm)

B. Schumm
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Flavor Tagging

bottom

charm

T. Abe
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Tracking
L Inner Radius 50 cm Outer Radius 200 cm Layers Fwd Disks B(Tesla) 144
TPC

SD 20 cm 125 cm 5
Si drift or µstrips

P 25 cm 150 cm 122
TPC

double-sided Si double-sided Si double-sided Si

5

5

5 3

3

5

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Tracking Resolution

B. Schumm
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Calorimeters
EM Tech Had Tech Inner Radius EM-outer Radius HAD-outer Radius Solenoid Coil EM trans. seg. Had trans. seg. L Pb/scin (4mm/1mm)x40 Pb/scin 196 cm 220 cm 365 cm outside Had 40 mr 80 mr SD W/Si (2.5mm/gap)x40 Cu or Fe/RPC (or Pb) 127 cm 142 cm 245 cm outside Had 4 mr 80 mr P Pb/scin (4mm/3mm)x32 Pb/scin 150 cm 185 cm 295 cm between EM/Had 30 mr 80 mr
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LC Detectors, Jim Brau, Fermilab, April 5, 2002


Calorimeter Resolution
Jet energy resolution
L: 0.18/Ejet SD: 0.15/Ejet

Di-jet mass resolution
L: 0.64/EZ SD: 0.72/EZ

e+e- 2 jets

e+e- ZZ

These are idealized studies, and resolutions will be worse. R. Frey
EM resolution: L: SD:
EM EM

/ E = (17% / E) (~1%) / E = (18% / E) (~1%)

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Muon Detection
Model L 24 в 5 cm Fe plates + RPCs r 1 cm (x 24) z 1 cm (x 4) coverage to ~ 50 mrad Model SD 24 в 5 cm Fe plates + RPCs r 1 cm (x 24) z 1 cm (x 4) coverage to ~ 50 mrad Model P 10 в 10 cm Fe plates + RPCs r 1 cm (x 10) z 1 cm (x 2) coverage to ~ 50 mrad
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NLC Cost Estimates
General considerations: Based on past experience Contingency = ~ 40% Designs constrained HE IR L SD LE IR P 359.0 M$ 326.2 M$ 210.0 M$

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NLC Cost Estimates
1.1 Vertex 1.2 Tracking 1.3 Calorimeter 1.3.1 EM 1.3.2 Had 1.3.3 Lum 1.4 Muon 1.5 DAQ 1.6 Magnet & supp 1.7 Installation 1.8 Management 1.9 Contingency Total
SUBTOTAL

L 4.0 34.6 48.9 (28.9) (19.6) (0.4) 16.0 27.4 110.8 7.3 7.4
256.4

SD 4.0 19.7 60.2 (50.9) (8.9) (0.4) 16.0 52.2 75.6 7.4 7.7
242.8

P 4.0 23.4 40.7 (23.8) (16.5) (0.4) 8.8 28.4 30.5 6.8 7.4
150.0

102.6 83.4

60.0

359.0 326.2 210.0
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Example Issues
1. What are the physics reasons for wanting exceptional jet energy (mass) resolution? How do signal/backgrounds and sensitivities vary as a function of resolution? Is mass discrimination of W and Z in the dijet decay mode feasible, and necessary? 2. How does energy flow calorimetry resolution depend on such variables as Moliere radius, / segmentation, depth segmentation, inner radius, B field, number of radiation lengths in tracker, etc.? 3. What benefits arise from very high precision tracking (e.g. silicon strip tracker); what are the limitations imposed by having relatively few samples, by the associated radiation budget? What minimum radius tracker would be feasible? 4. Evaluate the dependence of physics performance on solenoidal field strength and radius.
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The R&D Program
· Many topics require work · The follow few transparencies list many of the issues · see also
­ the following talks ­ the report from the International R&D committee

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The R&D Program

Calorimetry

energy flow need detailed simulation followed by prototype beam test demonstration further develop physics cases for excellent energy flow eg. Higgs self-coupling, WW/ZZ at high energy, recon of top and W for anomalous couplings?, others (SUSY, BR(H>160)) integrate E-flow with flavor tagging study readout differences for Tesla/NLC importance of K0/Lambda in energy flow calorimeter parametrize E-flow for fast simulation forward tagger requirements study effect of muons from collimators/beamline further development of simulation clustering tracking in calorimeter digital calorimeter study parameter trade-offs (R seg, layers, coil location, transverse seg.) in terms of general performance parameters in terms of physics outcome refine fast-sim parameters from detailed simluation integrate electronics with silicon detectors in Si/W reduce silicon detector costs engineer reduced gaps mechanical/assembly issues B = 5 Tesla? can scintillating tile Ecal compete with Si/W in granularity, etc.? crystal EM (value/advantages/disadvantages) barrel/endcap transition (impact and fixes)
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The R&D Program

Tracking

refine the understanding of backgrounds tolerance of trackers to backgrounds will large background be a problem for the TPC (field distortions, etc) are ionic space charge effects understood? study pattern recognition for silicon tracker (include vxd) study alignment and stability of silicon tracker what momentum resolution is required for physics, eg. Higgs recoil, slepton mass endpoint, low and high energy understand tracker material budget on physics physics motivation for dE/dx (what is it?) detailed simulation of track reconstruction, especially for a silicon option, complete with backgrounds and realistic inefficiencies include CCDs (presumably) in track reconstruction timing resolution readout differences between Tesla/NLC time structure role of intermediate layer tracking errors in energy flow (study with calorimeter) forward tracking role with TPC alignment (esp. with regard to luminosity spectrum measurement) develop thorough understanding of trade-offs in TPC, silicon options large volume drift chamber (being developed at KEK) development of large volume TPC (large European/US collaboration at work) development of silicon microstrip and silicon drift systems (being developed in US & Japan) study optimal geometry of barrel and forward system two track resolution requirements (esp. at high energy) this impacts calorimetry - how much? study K0 and Lambda efficiency impacts calorimetry? LC Detectors, Jim Brau, Fermilab, April 5, 2002 2D vs. 3D silicon tracker 36


The R&D Program

Vertx Det

resolve discrepancy in Higgs BR studies understand degradation of flavor tagging with real physics events compared to monojets (as seen in past studies) understand requirements for inner radius, and other parameters what impact on physics develop hardened CCDs develop CCD readout, with increased bandwidth develop very thin CCD layers (eg. stretched) segmentation requirements (two track resolution) 500 GeV u,d,s jets pixel size

Muons

requirements for purity/efficiency vs. momentum on physics channels understand role in energy flow (work with calorimetry) detailed simulation prototype beam tests mechanical design of muon system development of detector options, including scintillator and RPCs

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The R&D Program

Beamline, etc.

luminosity spectrum measurement beam energy measurement polarization measurement positron polarization systematics of the Blondel scheme veto gamma-gamma very forward system

General

is calibration running at Z0 peak essential/useful/useless?

Comment

In general it would be good if more work was done exercising the simulation code that has been put together under the leadership of Norman Graf. Much work has been devoted toward developing a detailed full simulation.

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North American Leadership
New leadership of Physics and Detectors Working Group (established by lab directors) Jim Brau, co-leader Mark Oreglia, co-leader Executive Committee Ed Blucher Dave Gerdes Lawrence Gibbons Dean Karlen Young-kee Kim Jeff Richman Rick van Kooten

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North American Leadership
Facilitate the progress of the working groups in developing the plans for the LC experiments Issues of focus the variables of the LC - how important to physics? time structure energy spectrum energy reach and expansion, luminosity two detectors? Positron polarization Gamma-gamma electron-electron and gamma-electron advance the understanding of key detector issues eg. energy flow calorimetry background tolerance vertex detector readout
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Coming Meetings
· North American
­ June 27-29, UC-Santa Cruz

· Other regions
­ April 12-15, St. Malo, France (DESY/ECFA) ­ July 10-12, Tokyo, Japan (5th ACFA Workshop)

· International
­ August 26-30, Jeju Is., Korea (LCWS 2002)
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Conclusions
The goals for the Linear Collider Detectors will push the state-of-the-art in a number of directions.
eg. finely segmented calorimetry for energy-flow measurement pixel vertex detectors (approaching a billion pixel system) integrated readout

Many techniques remain to be understood and developed.
see the following talks

Please get involved in your local effort and connect to the North American effort. come to Santa Cruz, June 27-29
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