Resonance results in 7 TeV pp collisions with the ALICE detector at the LHC

TL;DR

This paper measures short-lived hadronic resonances in 7 TeV proton-proton collisions using the ALICE detector to improve understanding of QCD models and establish baselines for heavy-ion collision studies.

Contribution

It provides the first detailed measurements of specific resonances in 7 TeV pp collisions and compares them with Monte Carlo models to test their accuracy.

Findings

Resonance yields and spectra are measured and compared with models.

Results help constrain QCD-inspired models and serve as a baseline.

Data shows discrepancies with some Monte Carlo predictions.

Abstract

Short lived hadronic resonances are a very important tool for the study of the dynamics of the matter produced in heavy-ion collisions since they should be sensitive to the medium properties such as temperature, density and expansion velocity. In particular they are sensitive to the time span between chemical and kinetic freeze-out of the hadronic phase of the fireball. The study of resonances in 7 TeV pp collisions is useful both in order to constrain QCD inspired models and to form a baseline for the production in heavy-ion collisions. The resonances $\mathrm{K}^{*0}$(892), $\phiup$(1020), $\Sigma(1385)^{\pm}$, $\Lambda$(1520), $\Xi$(1530) are reconstructed from their hadronic decay using data collected by the ALICE detector in pp collisions at 7 TeV. Their yields and $p_{\mathrm{T}}$ spectra are compared with Monte Carlo models such as PHOJET and different PYTHIA tunes.