Upsilon Analysis in p+p 2009 - pT Spectra

Upsilon cross-section in p+p collisions at sqrt(sNN) = 200 GeV, 2009 data - p_T Spectra

Note: All data plots are currently using -2 < nσ_e < 3 which is not optimized for this analysis!
Note: All data plots are using every run; run-by-run QA has not yet been completed!

• p_T Spectra (Drew)
  • 
    • First stab at pT spectrum of Upsilons from ee daughters.  This does not have efficiency corrections yet.
    • DY and bbbar are "subtracted" by multiplying the bin by the ratio of Yeild(Upsilon)/Yeild(Upsilon+DY+bbbar).
      • The errors are added in quadrature, which is correct only to first order for this DY and bbbar "subtraction".
    • <p_T> is just the mean of the bin, not the mean of the hits in the bin
      • Improvements on the way
• pQCD Upsilon p_T Spectra
  • p+p √S = 200 GeV
  • Pythia 8.1.53 with the following cuts:
    • Upsilon -> ee pair
      • Can only detect this decay channel
    • E_e1 > 4.0 GeV, E_e2 > 2.5 GeV
      • L2 trigger
        • need to verify the actual trigger.. changed from 2006 to 2008/9
    • |η_e1| < 0.5, |η_e2| < 0.5
      • mid-rapidity
    • cos(θ_e1e2) < 0.5
      • Ensure the electrons are roughly back-to-back
    • p_T e1 > 200 MeV, p_T e2 > 200 MeV
  • 
    • 2.5 M p+p->bbbar events for each pTHatMin
    • 1 GeV <= pTHatMin <= 10 GeV in steps of 0.10 GeV
      • Boosts the statistics of less likely collisions
      • Stacked histograms together
        • normalization factor: (cross section at X GeV) / (cross section at 1.0 GeV)
    • First bin is basically divided by 0 and is cutoff