The Effect of Multiplicity Cut on Particle Ratios at 7 TeV Proton-Proton Collisions

TL;DR

This study investigates how experimental cuts on rapidity and multiplicity affect the observed particle ratios in 7 TeV proton-proton collisions, suggesting that some observed phenomena may be artifacts of these cuts rather than intrinsic physics.

Contribution

The paper demonstrates that the apparent strangeness enhancement in proton-proton collisions can be explained by experimental cuts, highlighting the importance of considering these effects in data interpretation.

Findings

Adjusted thermal model explains measured particle ratios excluding proton to pion ratio.

Experimental cuts can cause apparent strangeness enhancement.

Measured hadronic composition differs from the true fireball composition due to cuts.

Abstract

The final state hadronic composition of proton-proton collisions at 7 TeV as a function of charged particle multiplicity density is studied. The thermal model is adjusted to match the experimental conditions in order to understand the effect of the experimental cuts on rapidity and multiplicity. This study indicates that the measured hadronic composition under a simultaneous cut on rapidity and multiplicity does not coincide with the fireball hadronic composition. Excluding proton to pion ratio, the adjusted model can explain the measured particle ratios. Therefore, the observed strangeness enhancement as a function of charged particle multiplicity density could be an effect of the experimental cuts.