Linear Collider TPC R

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Linear Collider TPC R D

• A sampling of this work by Ron Settles

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Goal

• To design and build an ultra-high performance
• Time Projection Chamber
• as central tracker for the LC detector
• where excellent vertex, momentum and
• jet energy precision are wanted

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LDC
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GLD
TPC
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The basic idea

• Cost-effective way of instrumenting a large
  volume
• With continuous tracking and a minimum of
  material
• Want the largest possible granularity
• -- i.e. 2 .109 voxels
• -- the best possible spoint resolution
• -- the best possible 2-track resolution

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Why

• High granularity to ensure robust operation in
  presence of large backgrounds
• Continuous tracking to ensure good
  momentum-measuring precision and gt98
  pattern-recognition eff. in jets

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ILC-TPC
A Large, High precision, High 3-D granularity
Time Projection Chamber operated
under a high magnetic field of 3 4 T

Unprecedented requirements to TPC especially for
granularity ? use of micro
pattern gas detector (MPGD) as a readout device
?
performance tests using prototypes
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LCTPC/LP Groups (16 August 06)
Americas Carleton Montreal Victoria Cornell Indi
ana LBNL MIT Purdue Yale
Europe LAL Orsay IPN Orsay Saclay Aachen Bonn DES
Y UHamburg Freiburg Karlsruhe MPI-Munich Rostock S
iegen NIKHEF UMM Krakow Bucharest Novosibirsk PNPI
StPetersburg Lund CERN
Asia Tsinghua CDC Hiroshima KEK Kinki
U Saga Kogakuin Tokyo UAT U Tokyo U
Tsukuba Minadano SU-IIT
Other groups interested?
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Examples of Prototype TPCs
Carleton, Aachen, Cornell/Purdue,Desy(n.s.) for
B0or1T studies Saclay, Victoria, Desy (fit in
2-5T magnets) Karlsruhe, MPI/Asia, Aachen built
test TPCs for magnets (not shown), other groups
built small special-study chambers
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MPI-Munich prototype for Wires, Gem and
Micromegas test in 5T at Desyand in 1T in beam
at Kek
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MWPC

• Very

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Replace sensor (wire) gitter previous slide by
either GEM or Micromegas
GEM Two copper perforated foils separated by an
insulator The multiplication takes place in the
holes. Usually used in 2 or 3 stages
Micromegas a micromesh sustained by 50-100 mm -
high insulating pillars. The multiplication
takes place between the anode and the mesh One
stage

• Very

200 mm
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GEM and Micromegas
S1/S2 Eamplif / Edrift
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Due to the high value of wt and the low grid
transparency, does it work in a magnetic field?
-gt Simulations in Aachen
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Prototype TPC
Field cage maximum drift length 260 mm
typical cathode H.V. - 6 kV
Readout plane effective area 100 mm100
mm MWPC GEMs
(3-stage) or
MicroMEGAS
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Experimental setup
We have conducted a series of beam experiments at
KEK PS.

• Beam mostly 4 GeV/c pions (0.5-4 GeV/c hadrons
  electrons)
• Magnet super conducting solenoid
• without return yoke (max
  field 1.2 T)

KEK p2 Beam Line
JECCEE inner diameter 850 mm effective
length 1 m
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Readout scheme and Gas
ALEPH TPC Electronics charge sensitive
preamp. shaper amp. (shaping time 500 ns)

digitizer (time bucket 80
nsec)