Detector Characteristics

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Patrick Spradlin, SCIPP trip to LLU, May 2, 2001 Detector Characteristics

description

Detector Characteristics. Detector Details. Vital Statistics. Overall detector area: 6.4 cm by 6.4 cm Wafer thickness: 400 m m Silicon: n-type substrate, p-type strips Large substrate resistivity: 5-8 k W Number of strips: 320 Strip pitch: 194 m m Strip width: 50 m m - PowerPoint PPT Presentation

Transcript of Detector Characteristics

Page 1: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Detector Characteristics

Page 2: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Page 3: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Detector Details

Page 4: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Vital Statistics

• Overall detector area: 6.4 cm by 6.4 cm• Wafer thickness: 400 m• Silicon: n-type substrate, p-type strips• Large substrate resistivity: 5-8 k• Number of strips: 320• Strip pitch: 194 m• Strip width: 50 m• AC coupled strip readout

Page 5: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Some Considerations in Estimating Energy from TOT

• Detector: Energy deposited => Charge Q in detector– Landau Distribution of deposited energy

– Shot noise

• Preamplifier and Front End Electronics– Threshold Calibration

– Charge Saturation: plateau in TOT vs. Input charge response

• Controller and Readout => TOT• Estimated charge Q => Estimated particle energy

Page 6: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Landau Energy Deposition, 400 m thick detector

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Deposited Charge (fC)

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35 MeVIntegrated Probability

Curves

Binned DistributionCurves

Page 7: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Landau Energy Deposition, 300 m thick detector

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30 MeV diff

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Integrated ProbabilityCurves

Binned DistributionCurves

Page 8: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Deposited Charge vs. Energy of Incident Proton*

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Proton Energy (MeV)

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400 um thicknes

300 um thickness

*Based on Monte Carlo Simulation

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Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Leakage Current

• Possible source of detector noise– Minimized with care. Usually a small noise

source– Shot noise. Mainly affects long shaping time.

• Temperature dependence:– Leakage current doubles for each 7°C rise in

detector temperature

• Bias voltage dependence:– Illustrated on following chart

Page 10: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

I-V Characteristics

HKM Factory Data, Detector 312.Factory Data for other 3 detectors

similar.25°C

SCIPP Data, Apr. 25, 200124°C

Page 11: Detector Characteristics

Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Energy DepositionComparison of Landau distribution (theoretical line)

with ToT data from GLAST

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Patrick Spradlin, SCIPP trip to LLU, May 2, 2001

Two MIP EventsComparison of theoretical and observed energy depositionfor possibility of 2 tracks passing through the same strip