December 12, 2016 - Mott Group Meeting

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Outstanding rates issues

  • Fits of Run I HI fail our method for determining MEAN and SIGMA (exponential fit fails).
    • Proposed solution - Use LO test runs corresponding to HI thickness runs to determine MEAN and SIGMA. Apply MEAN and SIGMA to Run I HI runs (flag in code?). Success will be that the Run I LO and HI data sets are no longer separated.
  • Once Run I LO/HI discrepancy solved we will have Run I rates and Run II rates from analysis where the uncertainty calculation is defined here.
    • Is the absolute uncertainty removed from calculation shown in file???
  • To this we have additional systematic uncertainty
    • Fluctuation of rates within a run (this will be the systematic over period of days e.g. stability of injector setup, slow drifts in the instrumentation), looks to be <1%
    • Fluctuation of rates between runs (this will be the systematic over period of months e.g. new calibration, new beam setup), looks to be ~5%
  • What else?

Background subtraction

  • There are two ways to determine the background event
    • Method I - Use one detector, learned that applying background works for one detector, but not other - Riad points out asymmetry flips sign for one detector
    • Method II - Use two detectors, super-ratio. I propose asymmetry should be similar (ideally equal), so how does this solve problem. Doesn't. Still need to apply +/- asymmetry in solution, or will background flip sign (+/- solution) ?