Update on Analysis of FNAL TB09 Jianchun Wang for the group Syracuse Univesity Jan 29 th,2010.

Post on 19-Dec-2015

218 views 0 download

Tags:

transcript

Update on Analysis of

FNAL TB09

Jianchun Wang

for the group

Syracuse UnivesityJan 29th ,2010

Testbeam Team at FNAL

June 2008: Tony Affolder, Marina Artuso, Alessandra Borgia, Lars Eklund, Karol Hennessy, Gwen Lefeuvre, Ray Mountain, Abdi Noor, Chris Parkes, Sheldon Stone, Jianchun Wang

April 2009: Marina Artuso, Alessandra Borgia, Torkjell Huse, David Hutchcroft, Ray Mountain, Jianchun Wang

Pixel system: David Christian (FNAL), Bruce Knapp (Nevis Lab), Jianchun Wang

More from remote

01/29/10 Jianchun Wang 2

301/29/10 Jianchun Wang

Introduction

PixelVELO

Pixel

YX YX

120 GeV proton beam

Pixel

Y

Scint

RR( )F

X

Z

Y

The system and analysis procedure: Independent DAQ systems for Pixel & VELO, sharing trigger signals. Events are matched offline. Tracks are reconstructed from pixel hits and fit to straight lines, multiple scattering is treated

separately. Pixel stations/modules are aligned within its own system. Velo sensors are aligned with respect to the pixel tracks. Tracks, corresponding Velo event IDs and alignment

parameters are saved in tracking data files. Pixel tracking data are fed to Vetra for VELO analysis.

Non-irradiated N-type R sensor (R/ f pair) Charge sharing & resolution for different pitches and track angles. Presented at 10/19/09 TREC meeting. Some plots are included here for comparison.

Differentially irradiated N-type & P-type R sensors (RR pair) Most probable charge vs irradiation particle fluence ( presented at 12/07/09 VELO meeting), some are updated

here. Most probable charge for different bias HVs. Detection efficiency and resolution.

Just

a re

mind

er

Basic on Charge Distributions

The FE electronics were under-powered, resulting in low gain. Most probable charge ~16 ADC instead of ~40.

Constant thresholds (seed=3.6, inclusion=1.8) are used (noise ~ 0.9 ADC counts). Thresholds are low enough to study irradiated sensors.

Gain differences are partially corrected using header heights.

Only hits that match with pixel tracks are looked at, to reduce the influence from uncertainty of noise hits.

Charge distributions are fit to Landau convoluted with Gaussian. The width of Gaussian is fixed to an average value so as to reduce the uncertainty on Landau MP.

In some cases there are shoulders/tails on low side that were not well understood. Fits are at peak areas. Fit range affects MP obtained from fit. MP represents, but not completely, the charge collection efficiency.

01/29/10 Jianchun Wang 4

Charge (ADC counts)

Sensor Charge Collection

Jianchun Wang 5

Tracks at 0-8 degrees, detector biased at 500 V.Hit map determined by pixel tracks that matche with VELO hits.

01/29/10

= – Y

X (

mm

)

N-type

= + Y

X (

mm

)

P-type

?

?

MP Charge At Different HVs

Jianchun Wang 6

Bias Voltage (V)

500 400 300200 100 50

01/29/10

N-type P-type

No HV scanned for middle part due to tight schedule.

It is difficult to extract correct MP when MP is close to threshold.

Comparing Different Electronics Settings

Jianchun Wang 7

N-typeKazu setting

P-typeKazu setting

N-typeChris setting

P-typeChris setting

optimized for sensors after irradiation.

Optimized for current running in the pit.

01/29/10

biased at 500 V

Detection Efficiency

01/29/10 Jianchun Wang 8

Due to the trigger scheme and different DAQ clock frequencies for the two systems, tracks seen by pixel and VELO are not necessarily the same.

Pixel tracks are matched with hits from one sensor (± 200 mm) to ensure this is a real track and seen by VELO.

We then look at the other sensor to see if there is hit that matches the track. The detection efficiencies are thus determined.

Beam profiles are not guaranteed to be the same for different conditions so the weight of dead areas changes for different condition runs.

A dead chip and few dead strips and certain border areas are removed.

In this way, the detection efficiencies reflect more precisely the effect of irradiation fluences and/or bias voltages.

Cleanup of Dead Strip & Borders

Jianchun Wang 9

X (mm)

Y (

mm

)

X (mm)

Y (

mm

)

N-sensor

P-sensor

N-sensor

P-sensor

Remove 6 bad

strips & borders

Remove 4 bad

strips & borders

hit position expectation that are unmatched

01/29/10

!

!

Detection Efficiency

Jianchun Wang 10

N-typeKazu setting

P-typeKazu setting

Normal incident tracks

Biased at 500 V

01/29/10

Not from 0

Detection Efficiency

Jianchun Wang 11

N-typeKazu setting

P-typeKazu setting

All angles

01/29/10

Bias Voltage (V)

500 400 300200 100 50

Detection Efficiency

Jianchun Wang 12

N-typeChris setting

P-typeChris setting

All angles

01/29/10

?

For Resolution Study

Jianchun Wang 13

Track Effective Angle (degree)

Select regions Y< –16 mm & Y > 16 mm.

Angles: 0-2, 2-4, 6-8 degrees

Pitches: 64-70, 70-80, 80-90, 90-100 mm

Y (mm)

Pitc

h ( m

m )

01/29/10

Resolution vs Pitch

Jianchun Wang 14

Normal Incidence (0.5)

R of R/ f pairN-type

0-2 degree

P-type0-2 degree

Fully irradiated (Kazu)

Fully irradiated (Chris)

Non-irradiated (Kazu)

Fully irradiated (Kazu)

Non-irradiated (Kazu)

Non-irradiated (Chris)

Error not fully estimated

R of R/f pair (Chris, 0 degree)

01/29/10

Resolutions are obtained through Gaussian fit to residual distributions, not just RMS due to bkg hits.

Tracking errors are removed.

Charge Sharing vs Pitch

Jianchun Wang 15

R of R/ f pair

N-type0-2 degree

P-type0-2 degree

Fully irradiated (Kazu)

Fully irradiated (Chris)

Non-irradiated (Kazu)

Non-irradiated (Kazu)

Fully irradiated (Kazu)

Non-irradiated (Chris)

Error not estimated

R of R/f pair (Chris, 0 degree)

Angle ( )-0.5 – 0.52.5 – 3.56.5 – 7.5

10.5 – 11.5

01/29/10

Resolution vs Pitch

Jianchun Wang 16

N-type

P-type

Error not fully estimated

R of R/ f pair

Angle ( )- 0.5 – 0.52.5 – 3.56.5 – 7.5

10.5 – 11.5

Irradiated Fully None

Angle (degree)0-22-46-8

01/29/10

Center of Residual vs HV

Jianchun Wang 17

N-typefully-irradiated6-8 degree tracks

64 – 70 mm

90 – 100 mm

80-90 mm

70 – 80 mm

Naïve interpretationMax difference ~150tan(8) = 21 mm

01/29/10

Center of Residual vs HV

Jianchun Wang 18

64 – 70 mm

90 – 100 mm80-90 mm

70 – 80 mm

P-typenon-irradiated6-8 degree tracks

01/29/10

Full depletion voltage ~ 110 V

Summary

Data on irradiated sensors are analyzed.

Most probable charge, detection efficiency, charge sharing and resolution are measured for different pitch, HV and irradiation dose.

Paper draft is on the way.

More ideas may come up while producing paper draft.

Some systematic errors already added, more will be included.

Suggests and contributions are welcome.

01/29/10 Jianchun Wang 19

Comparison Between N- and P-type Sensor

Jianchun Wang 20

P-type

N-type

01/29/10

More on N-type Sensor

Jianchun Wang 21

Artificial parameter from MP so that the shape looks more like the irradiation profile

Slopes in the transition region exhibit small discrepancy.

N-type sensor

01/29/10

MP vs HV

Jianchun Wang 22

N-type P-type

Non-irradiated

Vdep = 117±7 V

irradiated

irradiated

Fit with a naïve function

Non-irradiated

From non-irradiated

Vdep = 771±43 VVdep = 1218±96 V

01/29/10