Midrapidity Antiproton-to-Proton Ratio in pp Collisions at √s=0.9 and 7 TeV Measured by the ALICE Experiment

Submission Date: 
28/06/2010
Article Information
Submission Form
System: 
p-p
Energy: 
900 GeV
Energy: 
7 TeV
Abstract Plain Text: 

The ratio of the yields of antiprotons to protons in pp collisions has been measured by the ALICE experiment at s=0.9 and 7 TeV during the initial running periods of the Large Hadron Collider. The measurement covers the transverse momentum interval 0.45<pt<1.05  GeV/c and rapidity |y|<0.5. The ratio is measured to be R|y|<0.5=0.957±0.006(stat)±0.014(syst) at 0.9 TeV and R|y|<0.5=0.991±0.005(stat)±0.014(syst) at 7 TeV and it is independent of both rapidity and transverse momentum. The results are consistent with the conventional model of baryon-number transport and set stringent limits on any additional contributions to baryon-number transfer over very large rapidity intervals in pp collisions.