A Luminosity Detector for the Future Linear Collider

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A LuminosityDetector for the Future Linear
Collider
Ronen Ingbir
Prague Workshop
A Luminosity Detector for the Future Linear
Collider
HEP Tel Aviv University
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RD progress report
Approach Going back to pure electron
simulation
Bhabha Beamstrahlung Beam spread
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Detector Design
15 cylinders 24 sectors 30 rings 10800 cells
8 cm
0.31 cm Silicon
28 cm
0.34 cm Tungsten
R
L
6.10 m
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Reconstruction Algorithm
We explored two reconstruction algorithms
Events Num.
The log. weight fun. was designed to reduce steps
in a granulated detector 1. Selection of
significant cells. 2. Log. smoothing.
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Logarithmic Constant
400 GeV
After selecting We explored a more systematic
approach. The first step is finding the best
constant to use under two criteria 1. Best
resolution. 2. Minimum bias.
Constant value
Constant value
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Energy dependent constant
The goal is to find a global weight function.
Is the the log. weight constant really a constant
?
Constant value
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Shower reconstruction
What happens when we select the best log. weight
constant ?
Num. of Cells
Num. of Sectors
Energy portion ()
Num. of Cylinders
Most of the information is in the selected cells.
Engt90
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Detector optimization
Comparing new results Improvement without
changing the detectors granularity.
Num. rings
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Detector optimization
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Angular resolution
Results using pure electron simulation Can
we maintain same detector properties using a more
real MC ?
Beam Energy (GeV)
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Azimuthal resolution
Events Num.
E weight. Log. weight.
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Log. constant
400 GeV
Best constant value for is bigger then
the one. Meaning in this case best results
are obtained by using all the detector
information. Fixed non zero bias under
investigation.
Constant value
Constant value
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Log. weight Const function
Different cell size requires different weight
function. Low angle small cell size
smaller constant value (like in rec)
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Shower reconstruction
What happens when we select the best log. weight
constant ?
Num. of Cells
Num. of Sectors
Cell size determines selection mechanism
Num. of Cylinders
Energy portion ()
Engt98
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Azimuthal resolution
Results using pure electron simulation
Beam Energy (GeV)
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Energy resolution
Results using pure electron simulation
Acceptance cut
Energy Resolution
Beam Energy (GeV)
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Bhabha scattering
BHWIDE MC Simulation
Barbie -Geant 3.21 which includes
detector description for Tesla detector
The MC of physical process is the output of
bhabha scattering
The Barbie program was given to us by Leszek
Suszycki
Electron energy (GeV)
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Events selection - old approach
Gaussian fit and energy calibration based tail
cut
Detector signal
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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New Acceptance
Energy Resolution
More systematic analyses results with new
acceptance cut and improved resolution.
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Energy balance
New approach in this study Selecting events
using information from both sides of the
detector.
Right signal - Left signal
Left side detector signal
Right side detector signal
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Angular-azimuthal symmetry
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New approach Selecting events which are back to
back. The band cut must be wider than the
relevant resolution.
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HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Events selection
Detector signal
Detector signal
Acceptance cut
Energy balance cut
Detector signal
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Energy resolution - Bhabha
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Angular resolution - Bhabha
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Background studies
we included in the BHWIDE a background simulation
routine called CIRCE. This was suggested to us by
K. Moenig
Beamspread Boogert Miller note
(0.05) (hep-ex/0211021) Moenig talk in Zeuthen
(0.1)
Barbie Detector simulation
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Background studies
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Selecting events in background MC
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Energy resolution
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Angular resolution
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Luminosity
Measurement approach taking a known process
Bhabha scattering.
RD approach
RD status
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Conceptual experiment
real life algorithm
In real life we have a MC to help us understand
our measurements. We want to improve by a factor
of 10, but maybe a 10 disagreement between data
and MC is exactly the 10th factor we need. The
question is how well does our MC will describe
the future data ?
Working with both sides of the detector and
looking at the difference between the
reconstructed properties (In real life we dont
have generated properties)
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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How far are we ?
How well will our MC describe the future DATA ?
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1.DATA Reality MC 2. Real life algorithm
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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Summary and future goals
Using a more systematic approach results with
improved reconstruction algorithms and improved
resolutions. Our next step will be to explore
further the real life approach. Final
detector design recommendation.
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider
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The End
HEP Tel Aviv University
A Luminosity Detector for the Future Linear
Collider