Production of kshort, kstar(892)and phi(1020) in minimum bias events and kshort and lambda in jets in pbar p collisions at sqrt(s)=1.96 TeV

TL;DR

This study measures the transverse momentum distributions of various mesons and baryons in proton-antiproton collisions at 1.96 TeV, revealing insights into particle production mechanisms in minimum-bias events and jets.

Contribution

It provides detailed pT spectra for mesons and baryons, showing the similarity of pT slopes at high pT and the relation between soft jets and particle production in minimum-bias events.

Findings

pT slopes of kshort, kstar, and phi are similar at high pT

Lambda to kshort ratio becomes constant around pT ~ 5 GeV/c

More lambda baryons are produced in minimum-bias events at low pT

Abstract

We report measurements of the inclusive transverse momentum pT distribution of centrally produced kshort, kstar(892), and phi(1020) mesons up to pT = 10 GeV/c in minimum-bias events, and kshort and lambda particles up to pT = 20 GeV/c in jets with transverse energy between 25 GeV and 160 GeV in pbar p collisions. The data were taken with the CDF II detector at the Fermilab Tevatron at sqrt(s) = 1.96 TeV. We find that as pT increases, the pT slopes of the three mesons (kshort, kstar, and phi) are similar, and the ratio of lambda to kshort as a function of pT in minimum-bias events becomes similar to the fairly constant ratio in jets at pT ~ 5 GeV/c. This suggests that the particles with pT >~ 5 GeV/c in minimum-bias events are from soft jets, and that the pT slope of particles in jets is insensitive to light quark flavor (u, d, or s) and to the number of valence quarks. We also find that for pT <~ 4 GeV relatively more lambda baryons are produced in minimum-bias events than in jets.