Linear collider muon detector:

1
Linear collider muon detector

• Marcello Piccolo
• Amsterdam, April 2003

2
Agenda

1. Simulation
2. Started running with V 3.07 in Brahms. Few
   preliminary results
3. Results available also from the other side of the
   Atlantic.reasonable agreement.
4. RD Dedicated real work started or starting on a
   very short time base.

3
The new Brahms release

• The (Fortran) Code to full simulate the Tesla
  detector has been upgraded (thanks to Ties and
  Vasily)
• W-Si calorimeter option has been implemented
• Had Cal is based on the scintillator design.
• The Design Report muon detector has also been
  folded in.
• As of now it is possible to write a complete hit
  file containing
• Tracking detectors
• Calorimeters
• Muon detector

4
The new Brahms release (cont.)
5
Single positive muon efficiency
Here is the positive muon efficiency vs
momentum in the barrel detector.

• 95 eff.

• 85 eff.

• 90 eff.

6
Muon ID with dE/dx Correction
7
Pion Punch-through

• The response to p
• reported for 35000 events (Tesla)
• By M . Piccolo has been Reproduced The blue
  diamonds represent The SD
• Points for p after
• Normalization to account for the
• Difference in interaction length
• and statistics
• The Green stars
• Correspond to an
• Extra cut
• Requiring 5 planes with gt2 hits

10/700 1.4
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Here are the overall resultsbb events _at_500 GeV
The four spectra refer to Black generated
primary particles Red generated
m Green identified m Blue misidentified p
6000 evts
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Here are the overall resultsZH events _at_500 GeV
The four spectra refer to Black generated
primary particles Red generated
m Green identified m Blue misidentified p
7000 evts
10
Some RD points on the EU side of the Atlantic

• There are few issues that need to be addressed
• RPC (either bakelite or glass) have to be
  certified as rate capable.
• Gas mixes that grant to be neutron transparent,
  especially for the end-caps have to be found.
• Working regimes have to be investigated in
  different rates environment.

11
The Frascati Test Beam Facility
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Conceptual view of the facility
13
Simulated beam energy spectra
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Particle multiplicity
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Efficiency bidimensional mapA good bakelite RPC

• The overall efficiency
• For this module is
• (92.7.05 )
• Cosmic ray data

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Spatial resolutionA good bakelite RPC
Resolution of single RPC of the order of 7.0
mm. Fit with two gaussian distributions lead to
a ratio narrow/wide 101.
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Efficiency bidimensional mapA bad bakelite RPC
The overall efficiency For this module is e
(74.1 .1 ) Bad regions clearly Include the
perimeter And some of the spacers
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Efficiency bidimensional mapGlass RPCs

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Plateaux for two 1.1 m2 Glass RPCs
Turn on for streamer pulses on Glass
RPC. Detector dimensions 1x1.1 m2 Gas mix 60/35/5
Ar/Fr/Isob
20
Transverse and longitudinal efficiency
distributions Glass RPC
The tube structure of the Glass RPC is
apparent in the first plot where boundaries
between different Detectors can be seen as a
drop In the efficiency. The distribution along
the other coordinate is flat as expected
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Some RD points on the US side of the Atlantic

1. Here the idea is to develop a detector much in
   the line of Minos.
2. Scintillator extrusions read out with fibers then
   brought to the segmented anode of a p.m.
3. On top of that, many topics concerning the
   mechanical structure are being addressed.
4. Let me use Gene (Fisk) transparencies to
   illustrate their points.

22
R D is Needed Why?

1. How good is muon ID? For full LC menu?
2. Does E-flow benefit from m Cal?.
3. Requires integration with barrel and forward
   tracking and calorimetry, structural Fe,
   solenoid, mechanical support, cables, etc.
4. Robust design parameters - must be understood,
   optimized, cost estimated, reviewed.
5. Best m detector design?

23
Mechanical Engineering

1. Statics OK with 47T plates
2. Bolting appears to be possible structurally.
3. Open questions
4. Machined Fe?
5. Groove fitted?
6. Spokes a la CMS?
7. Bolted?
8. Opportunities for further ME work here.

24
Extruded Scintillator RD at Fermilab

• Studied Wavelength shifting (WLS) fiber readout
  of scintillator extrusions for possible future
  large scale detectors
• Scintillator MINOS extrusions
• 1 X 4 cm grooved
• TiO2 reflector
• Scintillator KEK prototype
• 1.2 X 2.5 cm hole down the middle
• TiO2 reflector
• WLS Kuraray Y11
• 1.2 mm 175 ppm (MINOS Standard)
• 1.0 mm 200 ppm
• 0.5 mm 200 ppm
• Photodetector - Visible Light Photon Counter
  (VLPC)
• Used D0 HISTE VI devices
• QE80-85
• Gain 60,000
  Alan Bross March 2003

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VLPC Tests with MINOS Scintillator

• 1.2 mm WLS fiber (MINOS) results using VLPCs.

Tests of 1.0 0.5 mm fibers, etc. Want to try
co-extr of scint fiber.
MINOS Ref. Value (sum)
Alan Bross March2003
26
Outlook and Conclusions

• Simulation tools of a new generation are being
  developed and used results are available both in
  Europe and U.S. and show comfortable agreement.
• Dedicated RD both for the scintillator option
  and for the parallel plate option are starting or
  have already started.
• A hard look is now being given to the engineering
  problems that the (not so small) amount of Fe we
  plan to use will bear on us.