Radius-wise track identification

1
Radius-wise track identification
Vladimir Gromov Nikhef, Amsterdam, the
Netherlands
February 28, 2012
2
Micro-pattern gas detectors layout and
features
Gas-avalanche detector combining a gas layer as
signal generator with a CMOS readout pixel array
Cathode (drift) plane
Cluster1
Cluster2
1mm 1m ? Drift gap
Cluster3
Gas Amplification Structure
400V 50um ? Avalanche gap
Readout chip
Cpar
Front-end circuit

• - particle track image (projection)
• 3D track reconstruction
• no sensor leakage current compensation
• low parasitic capacitance (less than 10fF)
• micro-discharges in avalanche gap
• Gas volume Correlated layers

TWEPP-09 V.Gromov
2
22/09/09
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Task definition Lorenz force and particle
trajectory
F q (V x B)

• items to clarify
• mathematic formula describing trajectory of
  charged particle moving in magnetic field
• definition of momentum of moving particle
• check /Common doc/Conferences/TWEPP-10/physics
  for pedestrians.pdf and http//en.wikipedia.org
  /wiki/Momentum

V
B
F
Timepix-3 V.Gromov
3
13/03/12
4
Detector layout
Z coordinate dont care dimension Cilindric 3D
coordinate system ? Polar 2D coordinate system
(transverse to Z-axis) 2D geometry r
radius f azimuth
angle
Pixel array 2cm2 256 rows x 32 columns
480µ
Common OR path ???
55µ

• items to clarify
• pT transverse momentum or the momentum that is
  perpendicular to the beamline of a particle
  detector
• why a high-pT particle moves radius-wise whereas
  a low-pT particle has a curved track

Pixel array 256rows x 32 cols
z
f
Periphery circuit
E
Contact pads
high-pT
B
a few rows
z
80cols?0.25mm 20mm
low-pT
The first full scale prototype FE-I4A consists of
an array of 80