1. Alon Attal Martin von der Mey Jay Hauser Mike Lindgren
PES Status Report
Alon Attal
Martin von der Mey
Jay Hauser
Mike Lindgren

2. Alon Attal – Calorimetry Meeting
Outline
Test Stand Studies
Implementation of Dead Strips in PES Reconstruction
Shower Fitting Using Minuit
11/13/2002
Alon Attal – Calorimetry Meeting

3. Alon Attal – Calorimetry Meeting
Test Stand
Goals
Reproduce/study effects seen in data.
Resolve timing issues.
Basic Configuration
Pulse LED for every L1 accept.
Filter between MAPMT and LED to attenuate light.
Light shines on one pixel only.
MAPMT can be read out with an ADMEM or SMXR.
11/13/2002
Alon Attal – Calorimetry Meeting

4. Alon Attal – Calorimetry Meeting
Timing
In both B0 and test stand data, we see unexpected phenomena between the primary and secondary time bucket.
Secondary time bucket
Primary time bucket
Gary Drake sees this as well and attributes it to the SMQIE chip.
Shouldn’t be a problem while running at 396ns bunch crossings.
11/13/2002
Alon Attal – Calorimetry Meeting

5. Alon Attal – Calorimetry Meeting
Observations
Response in Primary Bucket to Attenuated Signal
Primary time
bucket appears to
be functioning normally.
So far only normal levels of cross talk has been seen.
Still have a chance of fixing cross talk effects if we can determine the cause.
Future Tests:
Illuminating multiple pixels at once.
Operating under a magnetic field.
11/13/2002
Alon Attal – Calorimetry Meeting

6. Dead Strip Integration
Read from the DB the same way as the offline corrections.
Written out to run record.
Used (4.9.1?) for seed/shoulder clustering algorithm.
Important for shower fitting, discussed later.
11/13/2002
Alon Attal – Calorimetry Meeting

7. Alon Attal – Calorimetry Meeting
Using Dead Strips
Previously 2 clusters would have been reconstructed
on either side of the dead strip.
11/13/2002
Alon Attal – Calorimetry Meeting

8. Alon Attal – Calorimetry Meeting
Lorentz Fitting
Developing a fit to be used for
shower quality
better position resolution.
Current algorithm: 5 strip lorentzian
Parameters: Amplitude, Position, Width
Will also produce χ2
Uses Root Minuit package
Doesn’t use test beam data
11/13/2002
Alon Attal – Calorimetry Meeting

9. Alon Attal – Calorimetry Meeting
Fitting Example
Values returned from fit:
Amplitude = 41.3 / 41.3
Position = / 2.0
Width = 0.81 / 0.82
Less susceptible to dead strips and cross talk.
11/13/2002
Alon Attal – Calorimetry Meeting

10. Alon Attal – Calorimetry Meeting
Current Work
Currently we are trying to fully understand how the fit works and how changes in the inputs affects the results.
Studying fit with data – plug W’s and simulation – single electron.
Choosing proper parameter limits and fit criteria for robustness.
Developing errors based on
Typical energy resolution
Calibration precision
Pedestal
11/13/2002
Alon Attal – Calorimetry Meeting

11. Alon Attal – Calorimetry Meeting
Fit Distributions
11/13/2002
Alon Attal – Calorimetry Meeting

12. Alon Attal – Calorimetry Meeting
Still Ahead
Finalize parameter limits.
Test background rejection and signal acceptance.
Release as optional method.
11/13/2002
Alon Attal – Calorimetry Meeting