Muon Week (09/2007) USC ATLAS Group Meeting Woochun Park September - - PowerPoint PPT Presentation

Muon Week (09/2007)

Woochun Park September 14, 2007 USC ATLAS Group Meeting

Content

• Muon efficiency problem at Endcap
• New tracking algorithm development.
• Installation Progress
• CscReconstruction Report
• Micromegas

M5 includes CSC chambers

Csc Cluster Reconstruction in new simulation (13.0.2)

Introduction

• Gas gain in simulation is reduced from 1.0x105 to 0.58x105.
• Strip charges are reduced accordingly.
• In cluster reconstruction, threshold algorithm is used. We

need to make sure that all the parameters are reasonable for the new simulation.

Cluster Charge Distribution

QL+QP+QR

Cluster Charge Distribution on #strips

• The more cluster charge distribution spreads, the more strips in cluster.

Black Line : 3 strips Blue Line : 4 strips Red Line : 5 strips QL+QP+QR

#Strips of Cluster Depending on Cluster Charge

12.0.6 thr=20k max=5

13.0.20 thr=16k max=5

ClusterStatus Depending on Cluster Charge

12.0.6 thr=20k max=5

13.0.20 thr=16k max=5 1.4/0.1 1.0/0.1 6 3.6/0.1 7.2/0.2 2.5/0.1 0.3/0.0 1.7/0.1 83.5/0.6 13.0.20 2.6/0.1 7.9/0.2 1.0/0.1 0.1/0.0 1.8/0.1 85.6/0.7 12.0.6 11 5 4 3 2 %

Unspoiled Edge Multipeak Narrow Wide Skewed Inconst.

Pull Width Dependence

eta Measured Strip Position Unpoiled + Spoiled Clusters Unpoiled Clusters 13.0.20

Pull Width Dependence On Calculated Error

12.0.6 13.0.20

Residual on Cluster Charge

Cluster Charge (ADC counts) 500 1000 1500 2000 2500 3000 3500 Clusters/(40 ADC counts) 50 100 150 200 250 300

|<0.15 φ 0.05<|tan

Resolution (mm) 0.05 0.10 0.15 0.20 0.25 0.30

12.0.6 thr=20k max=5

13.0.20 thr=16k max=4 13.0.20 thr=16k max=5 Arrow indicates about 20% height of peak

max : max # strip in cluster Cosmic result QL+QP+QR

In cosmic data, spoiled clusters are included which make resolution worse at the high tail.

Calculated Error vs. Cluster Charge

• Error is smaller than the residual.
• Regardless of release, error estimates depending on cluster charges are similar.
• This can be shown in pull width dependence on cluster charge in next page.
• We may want to introduce additional error which is proportional to cluster charge.

12.0.6 thr=20k max=5

13.0.20 thr=16k max=4 13.0.20 thr=16k max=5

Pull Width Dependence on Cluster Charge

12.0.6 thr=20k max=5

13.0.20 thr=16k max=4 13.0.20 thr=16k max=5

max : max # strip in cluster QL+QP+QR

Good efficiency on Cluster Charge

12.0.6 thr=20k max=5 0.995±0.001

13.0.20 thr=20k max=5 0.986±0.001 13.0.20 thr=16k max=4 0.992±0.001 13.0.20 thr=20k max=4 0.989±0.001 13.0.20 thr=16k max=5 0.987±0.001

Good effi 12.0.6 thr=20k max=5

13.0.20 thr=16k max=4 13.0.20 thr=16k max=5 Arrow indicates about 20% height of peak

max : max # strip in cluster QL+QP+QR

Good efficiency dependence on #strip and cluster charge

• If cluster has 4 or 5 strips, more chance to be bad

measurement.

13.0.20 thr=16k max=5

Black Line : 3 strips Blue Line : 4 strips Red Line : 5 strips QL+QP+QR

Good Efficiency and #Strips

• The more charges in three

strips means that the other strips may contain significant amount of charge in #strips =4 or 5 case.

• How about include QLL and

QRR in QL and QR??

Bad Efficiency on Cluster Charge

13.0.20 thr=20k max=5 0.014±0.001 13.0.20 thr=16k max=4 0.008±0.001 13.0.20 thr=20k max=4 0.011±0.001 13.0.20 thr=16k max=5 0.012±0.001

12.0.6 thr=20k max=5 0.005±0.001

Arrow indicates about 20% height of peak

12.0.6 thr=20k max=5

13.0.20 thr=16k max=4 13.0.20 thr=16k max=5

QL+QP+QR Mostly from 4 strips and 5 strips (p15) Bad effi

Spoiled Fraction on Cluster Charge

13.0.20 thr=20k max=5 0.184±0.003 13.0.20 thr=16k max=4 0.223±0.003 13.0.20 thr=20k max=4 0.206±0.003 13.0.20 thr=16k max=5 0.171±0.003

12.0.6 thr=20k max=5 0.144±0.003

Arrow indicates about 20% height of peak

12.0.6 thr=20k max=5

13.0.20 thr=16k max=4 13.0.20 thr=16k max=5

QL+QP+QR

This behavior is understood in page 19.

Spoiled Fraction

Eta Resultion

• Position residual is correlated to strip charge amount. The more

charges are deposited, the better resolution.

• Threshold is 16k e-.
• max # strips per cluster = 5(left) and 4(right).
• Compared to 41microns in 12.0.6 simulation, the resolution becomes

wider.

63.2µm 61.4µm Max=5 Max=4

Eta Pull Distribution

Max=5 Max=4

• Threshold is 16k e-.
• max # strips per cluster = 5(left) and 4(right).
• Compared to 1.004 in 12.0.6 simulation, pull width is comparable.
• Red circle indicates contribution of cluster with 5 strips. These cluster gives

better residual than others while errors are conservative.

• ClusterStatus

– 0: Unspoiled – 2: Edge – 3: Multipeak – 4: Narrow – 5: Wide – 6: Skewed – 11: Inconsist.

ClusterStatus Depending on Cluster Charge

13.0.20 thr=16k max=5

The more cluster charge, the more failed

• wing to too wide.

# Strips Depending on Cluster Charge

13.0.20 thr=16k max=5

The more cluster charge, the more number strips cluster has.

Number of strips vs cluster charge.

Orange line indicates the current cuts [3-5] for # strips of cluster.

# Strips Depending on Cluster Charge

12.0.6 thr=20k max=5

The more cluster charge, the more number strips cluster has.

Number of strips vs cluster charge.

Orange line indicates the current cuts [3-5] for # strips of cluster.

Conclusion & To do

• Gas gain is reduced to 0.58x105 from 1.0x105 in Csc

simulation (13.0.20).

– Cluster charges are decreased accordingly. – No calibration is needed. – Two parameters don’t have to be changed: Strip charge error (4300e) and angular error term (0.57mm) – Less Threshold is suggested (16k as proposal).

• Bad fraction is increased by factor of two:

– Maximum # strip 4 is considered instead of 5. – Additional error depending on cluster charge may be necessary. – Additional Strips in Charge Ratio Method (QLL, QRR) may be needed. If so, then error will be more conservative. – Then, we need to tune threshold parameter. – Method needs to be developed to discriminate bad cluster from good cluster using variables such as total charge, 4th strip charge,

To analyze cosmic data

• Pedestal and noise information should be accessed

through conditionDB for run by run base.

• Pedestal for each strip should be subtracted before we do

stripFit on sampleCharges.

• Noise for each strip is used as a charge measurement

error.

• Ketevi is working on CalibrationTool package to do this

(one week??).

Measurement of Pedestal and Noise

• Multiple measurements.

Pedestal Distribution

Layer Chamber

External Pulser Trigger

• K. Nikolopoulos University of Athens – Muon Reconstruction Meeting – May 3rd 2007

Noise Distribution

Noise increase as a function of strip number due to increasing length of strips towards the top of the chamber.

Layer Chamber

External Pulser Trigger

• K. Nikolopoulos University of Athens – Muon Reconstruction Meeting – May 3rd 2007

12.0.3 13.0.2 Cosmic

Muon Deterctor for SLHC

• Micro Pattern Gas Detector workshop at

http://indico.cern.ch/conferenceOtherViews.py?view=standard&confId=16213

• South Carolina is committed to Micromegs R&D (Test beam and proposal).
• Beam test scheduled from Oct 17 to Nov 11. Plan to be at CERN around Oct 8.
• My job is to participate in beam test, collect data, and analyze them. Hope to

report it at NIM.

• Refer to J. Wotschack’s presentation at the workshop.