The ATLAS Hadronic Endcap Calorimeter

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The ATLAS Hadronic Endcap Calorimeter
James L. Pinfold For the ATLAS Hadronic Endcap
Calorimeter Group
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Hadronic Endcap CalorimeterLAr-Cu sampling
calorimeter covering 1.5 lt h lt 3.2

• GOOD HE JET RESOLUTION (10 l of active
  cover.)
• FULL HECFCAL h COVER (1-5-gt 4.8) for good
  Etmiss determination.
• PUNCHTHROUGH TO m SYSTEM REDUCED by 11l
  thickness of HECsupport.

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Hadronic Endcap Calorimeter Construction
Responsibilities

• Absorber plate production
• Alberta
• Dubna
• Protvino
• Readout foils
• Mainz
• TRIUMF
• EST boards
• Lebedev
• Module stacking centres
• Dubna
• MPI Munich
• TRIUMF
• Protvino
• Cold electronics (preamps) cabling harness
• MPI Munich
• Calibration system
• KOSICE
• Mainz

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Hadronic Endcap Segmentation
Front mod. 25 plates, rear mod. 17 plates

• Composed of two wheels per end, 32 modules per
  wheel
• Front wheel 67 tonnes 25 mm Cu plates
• Rear wheel 90 tonnes 50 mm Cu plates
• Channel count for both endcaps, 4416

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HEC MODULE
PAD boards
EST boards
Honeycomb
Copper plates
Tie Rods
Connecting Bars
Cold Electronics
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HEC Readout

• Electrostatic Trans- former readout
• Distance between
  Cu plates 8.5 mm
• LAr gaps 1.954 mm
• Robust against HV shorts

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Cu Absorber Plate Production

• Three sites Alberta, Dubna, Protvino
• Roughly one sector(1/32nd) per month can be
  machined at Dubna Protvino. Since June 1st 1999
  2-gt3 per month can be machined at Alberta
• Estimate machining finished by early 2002.
• Eg Cu machining _at_ Alberta, using the CSR
  advanced machining facility

See the machining in realtime moving images
http//129.128.162.80/webcam/JavaCam.html
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Series Production of Modules

• 1st module completed in Munich on 4/16/ 99.

Module under HV test at TRIUMF
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Quality Control

• Quality control procedures defined in October
  1997, updated in November 1998.
• 2000 testbeam QC database started at CERN
• 2001-gt merging of QC databases from CERN
  institutes into LAr QC database.

Go-NoGo jigs
Cu density check
Template check
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Cold Electronics
3 PSBs on back of each front module 2 PSBs on the
back of each rear module
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Cold Testing
(7 out of 8 modules will be cold tested)
4 modules in cold test cryostat
Modules prepared for a cold test
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Test Beam Setup
(1 in 8 modules will be beam tested)
Rotating to vertical
Mating the modules
Modules in the cryostat
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Stacking Insertion of HEC wheels into the
Cryostat
Stacking
Crane
Wheel
Rotator
Air Pads
T6 Cryostat
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Recent Future Testbeam
Test-beam summer 2000 involving 6 series modules
in the H6 beamline. Analysis of results recently
accepted by NIM Summer 2001 2
successful test-beam periods . H6 Joint
EMEC-HEC test planned for the August of 2002.
Using H1 cryostat deploy 1) EMEC 2) HEC FRONT
3) HEC REAR (HALF DEPTH)
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Test Beam Results (1)Energy resolution for
electrons

• Reported here are key results from the test of 6
  series production HEC modules
• Results obtained in the summer of 2000

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Test Beam Results (2)

• Spatial uniformity of response to electrons as a
  variation of EM calib. Const. variation

Non-uniformity lt 1
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Test Beam Results (3)Energy resolution for pions
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Testbeam Results(4) Muon Detection

• Using 150 GeV muons (most prob. muon signal

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Testbeam Results(5) e/h Ratio
Ratio of response to electrons and hadrons
CMC is an energy dep. leakage correction
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Final Remarks

• Series production well underway 57 (76/134)
  modules stacked on schedule
• 42 (57/134) modules Cold Tested.
• All HEC only beam tests finished this summer!
• Joint EMEC-HEC test beam next summer.
• Joint EMEC-HEC-FCAL test in 2003
• Stand/Table/Rotator for installation ordered and
  due December 2001.
• Assembly area and clean rooms in Bat.180 ready.
• Assembly of the HEC will start in March 2003 in
  Bat. 180 at CERN.