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

h+/h-: Comparison Between the Reproduction vs the Original Production

~10% of the 2009 p+p 200 GeV was reproduced (http://www.star.bnl.gov/public/comp/prod/prodsum/production2009_200Gev_Single.P11id.html). We ran over the available Upsilon stream reproduction and compared with the results from the original production. The reproduction was generally found to have a different index for each set of electron pairs, so the following cuts were used to match Upsilon candidates:

Same Run ID and Event ID

|Delta Vz| < 1.0 cm

 

 

 

Same Charge (daughter 1 reproduction = daughter 1 original production, daughter 2 reproduction = daughter 2 original production)

 

-1.29 < nSigmaElectron 3.0 (used in the analysis for the original production)

We projected the m_{old} over the range of 8 to 11 GeV to see the effect on the Upsilon candidate:

 

There is a smearing of mass, ~1/3 GeV, with the reproduction compared to the original production. We specifically chose the 8 < m_{old} < 11 GeV/c^2 range to see how the Upsilons would be affected for a cross section measurement.