Measurements are presented of the production of primary K0S and Λ particles in proton-proton collisions at √s=7 TeV in the region transverse to the leading charged-particle jet in each event. The average multiplicity and average scalar transverse momentum sum of K0S and Λ particles measured at pseudorapidities |η|<2 rise with increasing charged-particle jet pT in the range 1–10 GeV/c and saturate in the region 10–50 GeV/c. The rise and saturation of the strange-particle yields and transverse momentum sums in the underlying event are similar to those observed for inclusive charged particles, which confirms the impact-parameter picture of multiple parton interactions. The results are compared to recent tunes of the pythia Monte Carlo event generator. The pythia simulations underestimate the data by 15%–30% for K0S mesons and by about 50% for Λ baryons, a deficit similar to that observed for the inclusive strange-particle production in non-single-diffractive proton-proton collisions. The constant strange- to charged-particle activity ratios with respect to the leading jet pT and similar trends for mesons and baryons indicate that the multiparton-interaction dynamics is decoupled from parton hadronization, which occurs at a later stage.
Measurement of neutral strange particle production in the underlying event in proton-proton collisions at √s=7 TeV
L. Bianchini;MARTINI, LUCA;MESSINEO, ALBERTO MARIA;RIZZI, ANDREA;TONELLI, GUIDO EMILIO;A. C. Marini;
2013-01-01
Abstract
Measurements are presented of the production of primary K0S and Λ particles in proton-proton collisions at √s=7 TeV in the region transverse to the leading charged-particle jet in each event. The average multiplicity and average scalar transverse momentum sum of K0S and Λ particles measured at pseudorapidities |η|<2 rise with increasing charged-particle jet pT in the range 1–10 GeV/c and saturate in the region 10–50 GeV/c. The rise and saturation of the strange-particle yields and transverse momentum sums in the underlying event are similar to those observed for inclusive charged particles, which confirms the impact-parameter picture of multiple parton interactions. The results are compared to recent tunes of the pythia Monte Carlo event generator. The pythia simulations underestimate the data by 15%–30% for K0S mesons and by about 50% for Λ baryons, a deficit similar to that observed for the inclusive strange-particle production in non-single-diffractive proton-proton collisions. The constant strange- to charged-particle activity ratios with respect to the leading jet pT and similar trends for mesons and baryons indicate that the multiparton-interaction dynamics is decoupled from parton hadronization, which occurs at a later stage.File | Dimensione | Formato | |
---|---|---|---|
PhysRevD.88.052001.pdf
accesso aperto
Tipologia:
Versione finale editoriale
Licenza:
Creative commons
Dimensione
685.24 kB
Formato
Adobe PDF
|
685.24 kB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.