Nate Baillie

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• Nate Baillie
• College of William and Mary

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Modification to Track Fitter

• charge weighting now occurs before line fit.
  instead of each data point being weighted against
  all others, a weighted average is performed for
  each slice in time
• This change had no noticeable improvement on
  proton source search
• Monte Carlo needed to study multiple scattering

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dE/dx distribution from TUNL2

• The Data Cuts
• Black curve all events
• Red curve only proton events
• Green curve proton events which went all the
  way through chamber
• Mean value of green curve is 33 MeVcm2 / g
  which Bethe-Bloch says corresponds to an incoming
  proton energy of 9 MeV
• This data run had no Mylar absorbers outside of
  the exit window
• The energy calibration is probably flawed but
  its the right ballpark

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Incoming Energy Spectrum

• Extracted incoming proton Energy from NIST data
  for protons in Argon
• The binning needs work shape is all wrong right
  now
• However the peak value of 9 MeV is valid

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Next Steps

• Insert Bethe-Bloch into fitting code
• Convert line fitter from (x,y,z) to (r, ?, z)
• Monte Carlo of multiple scattering to see if I
  will ever be able to find beam location
• Continue Pad shape studies????
• Questions/comments?