LCD-ALCPG

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LCD-ALCPG

• Presentation at the ALCPG-SLAC
• Meeting
• SUSY Analysis of Sleptons
• Problems, Solutions, Improvements
• January, 2004

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LCD-ALCPG

• THE GROUP
• Shirley Choi, Bradford Dobos, Tyler Dorland,
  Eric Erdos,
• Jeremiah Goodson, Jack Gill, Jason Gray
• Andrew Hahn, Eric Kuhn, Alfonso Martinez
• Kyle Miller, Uriel Nauenberg, Joseph
  Proulx,
• Jesse
  Smock

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LCD-ALCPG

• ACTIVITIES
• Simulation of Supersymmetry. New method to
  overcome the negative effects of beamstrahlung
  and bremmstrahlung.
• The Benefits of Positron Polarization.
• Resolution on M0 , M1/2 from mass measurement

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LCD-ALCPG

• Simulation of Selectron Production
• Case Study
• Consider Case SPS3 , M1/2 400 GeV, M0 90
  GeV.
• Mass of eR 178.3 GeV, Mass of eL 287.1 GeV,
  Mass of ?01 160.6 GeV.
• Compare Fits with Beam and Bremmstrahlung and
  without.
• We use the e - e - Energy Spectra Substraction
  Technique to remove Standard Model Background.

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LCD-ALCPG

• Selectron Production
• e - e - Energy
  Spectra

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LCD-ALCPG

• Resultant Fits to Energy Edges
• No Bremm
  Bremm

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LCD-ALCPG

• New Method to Determine Masses
• Compare Energy Spectrum to those Generated with
  different parameters encompasing the correct one.
• Do a Chi Square Fit to the Spectra Comparison.
• Choose the minimum and determine the masses.

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LCD-ALCPG

M1/2 400 , M0 90 expec. value.
M1/2 1.5 from 400, M0 90
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LCD-ALCPG

• Chi Square Fit Distribution
• 
  
• 
  M1/2(expec.) 400 GeV
• 
  M1/2(fit)400.220.19 GeV
• 
  M0 fixed at 90 GeV

-0.54
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LCD-ALCPG

• M1/2 vs M0 curves for Msel L values M1/2 vs M0
  curves for Msel R values

Not physical
Not physical
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LCD-ALCPG
?

• M1/2 vs M0 curves for M (c10 )

No dependence on tan(? )
Not physical
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LCD-ALCPG

• Effect of Positron Polarization
• What do we observe if we have positron
• polarization. We studied 80 e -, 80 e.
• Applied to Selectrons and Smuons.

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LCD-ALCPG
?
?

• Electron, Positron Energy Spectrum from e
  e - ? all e e
• e- Spect.e - 80R e Spect. e-
  Spect.e - 80R e Spect.
  

e 80 R
e 80 L
e 0 pol.
e 0 pol.
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LCD-ALCPG
?
?

• Muon Energy Spectrum from e e - ? m m
  
• e - 80 R e 80 L
  e 80 L e 80 R

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LCD-ALCPG

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LCD-ALCPG

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LCD-ALCPG