Sensor and Readout Status of the PIXEL Detector

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Sensor and Readout Status of the PIXEL Detector
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Talk Structure

• Sensors
• Readout
• Development and Prototyping with test results

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(No Transcript)
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IPHC Functional Sensor Development

• 30 x 30 µm pixels
• CMOS technology
• Full Reticule 640 x 640 pixel array

All sensor families
Mimostar 2 gt full functionality 1/25 reticule,
1.7 µs integration time (1 frame_at_50 MHz clk),
analog output. (in hand and tested)
Phase-1 and Ultimate sensors gt digital output
(in development)
Data Processing in RDO and on chip by generation
of sensor.
The RDO system design evolves with the sensor
generation.
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HFT PIXEL Readout Functional Goals

• Triggered detector system fitting into existing
  STAR infrastructure (Trigger, DAQ, etc.)
• Deliver full frame events to STAR DAQ for event
  building at approximately the same rate as the
  TPC (1 KHz for DAQ1000).
• Reduce the total data rate of the detector to a
  manageable level (lt TPC rate).
• Reliable, robust, cost effective, etc.

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Mimostar Data Flow
System Goal 10 Sensors / Ladder 33 Ladders 135M
Pixel
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Raster scan
Data examined Per clock cycle
Implemented in FPGA on daughter card
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Cluster Finder Efficiency
Real Data taken with MIMOSTAR2 detectors by IPHC
Traditional ADC Sum Method
2 Threshold FPGA method
Cut on the central pixel goes from 14 to 8 ADC
counts (left to right) every 1 ADC. 1 ADC 7.1
e-.
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PIXEL Data Rates (1 KHz)

• Rate _at_ R1 (2.5cm) 52.9 / cm2
• Rate _at_ R2 (6.5cm) 10.75 / cm2
• Rate _at_ R3 (7.5cm) 8.76 / cm2 (at L 1027)
• Average event size 114 KB
• Data Rate 114 MB/sec at 1KHz
• 33 fibers
• 33 RORC (6 readout PCs)

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Prototype 3 Sensor Telescope

• We tested the functionality of a prototype
  MIMOSTAR2 detector at the LBNL ALS and then in
  the environment at STAR during the last three
  weeks of the 2006-2007 run at RHIC. Our goal was
  to gather information on
• Charged particle environment near the interaction
  region in STAR.
• Performance of our cluster finding algorithm.
• Performance of the MIMOSTAR2 sensors.
• Functionality of our interfaces to the other STAR
  subsystems.
• Performance of our hardware / firmware as a
  system.
• The noise environment in the area in which we
  expect to put the final PIXEL detector.

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Telescope Electronics / RDO
MimoStar2 chips on kapton cables
DAUGHTER CARD
MOTHER BOARD
Control PC (Win)
STRATIX
Acquisition Server (Linux)
RORC SIU
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Telescope Sensors and Mechanical Housing
3 MIMOSTAR2 chips mounted as close together as
reasonably possible on low mass kapton cables in
a telescope configuration.
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Mimostar2 Telescope test at the ALS
1.2 GeV electrons at the ALS Booster Test
Facility Important Due to un-terminated DAC pads
on the sensor, our noise level was double the
value achieved under ideal conditions at IPHC in
France. IPHC gt11-15 electrons at 30º C LBL gt
30-35 electrons at 28º C
MPV 49 (Standard) and 43 (Radtol) ADC counts at
230 electrons
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Efficiency and Accidental rates for ALS test
Merged cluster data typically 2-3 hits per
cluster. Increased noise in sensors results in
reduced performance.
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Telescope Installed at STAR
Magnet Pole Tip
Beam Pipe
Electronics Box
Telescope head 1.45 m from interaction point
just below beam pipe.
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STAR Prototype Run Results
Typical CDS full frame event in one sensor.
Clusters are clearly visible above the noise
level.

• Measured charged particle flux was 3.9 merged
  clusters per sensor (1.7 µs integration time,
  L8?1026 cm-2s-1 ).
• Noise level of system in the STAR environment was
  7.48 ADC counts, comparable to laboratory and ALS
  measurements.
• Prototype system integrated with STAR Trigger,
  slow control and run control sub-systems. Events
  delivered to DAQ standard RDO PC.
• TLD measured dose at head position, 325 rad over
  running time. This scales to an integrated dose
  of several hundred Krad / run.

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Distribution of track angles in Mimostar2
telescope
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Summary for beam runs

• RDO system with data sparsification implemented
  and functional for Mimostar2 sensors.
• Prototype system characterized, but with
  increased noise.
• Fully functioning interfaces between our
  prototype detector and STAR detector
  infrastructure.
• Completed measurements of detector environment at
  STAR including induced electronic noise.

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Some tasks and milestones for the next year

• August 2008 delivery of Phase-1 sensors from
  the foundry.
• Develop new generation RDO system based on
  Virtex-5 FPGA.
• Testing of Mimostar2, Mimostar3 and Mimosa22e
  sensors.
• Prototype low radiation length cable.

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• fin