Production of K $$^{*}$$ ∗ (892) $$^{0}$$ 0 and $$\phi $$ ϕ (1020) in p–Pb collisions at $$\sqrt{s_{{\text {NN}}}}$$ s NN = 5.02 TeV

Abstract

The production of K(892) and (1020) mesons has been measured in p–Pb collisions at 5.02 TeV. K and are reconstructed via their decay into charged hadrons with the ALICE detector in the rapidity range . The transverse momentum spectra, measured as a function of the multiplicity, have a p range from 0 to 15 GeV/c for K and from 0.3 to 21 GeV/c for . Integrated yields, mean transverse momenta and particle ratios are reported and compared with results in pp collisions at 7 TeV and Pb–Pb collisions at 2.76 TeV. In Pb–Pb and p–Pb collisions, K and probe the hadronic phase of the system and contribute to the study of particle formation mechanisms by comparison with other identified hadrons. For this purpose, the mean transverse momenta and the differential proton-to- ratio are discussed as a function of the multiplicity of the event. The short-lived K is measured to investigate re-scattering effects, believed to be related to the size of the system and to the lifetime of the hadronic phase.

Role of system size in freeze-out conditions extracted from transverse momentum spectra of hadrons

“…The sum goes over all available p+Pb data points up to p T = 2.5 GeV/c [35][36][37]. For 1FO, we have varied all the three parameters T , ρ max and τ f to arrive at the best [21,22] and data [35][36][37] is shown for three centralities: 0 − 5%, 10 − 20% and 60 − 80% in three different FO schemes at 0 < ycm < 0.5. The gross features of the spectra comparison seems to be independent of the freezeout scheme.…”

Resonance suppression from color reconnection

“…1, we present the K Ã /K integrated ratio as a function of multiplicity predicted by PYTHIA8 for pp collisions at 7 TeV without CR (black squares), with "MPI-based" (blue hollow squares) and "More QCDbased" (blue solid squares) compared to measurements by ALICE (shaded gray area) in p-Pb collisions at ffiffiffiffiffiffiffi ffi s NN p ¼ 5.02 TeV [22]. While of course these are two different colliding systems and energies, a preliminary version of the K Ã /K ratio in pp collisions at 7 TeV follows the same trend as the p-Pb data [12], and therefore using the p-Pb data as a proxy for the as of yet unpublished pp measurement is reasonable.…”

Description of ϕ-meson production in hadronic and nuclear collisions at very high energies

“…The comparison with the corresponding available experimental data is also shown. Unfortunately, only one experimental point by the ALICE Collaboration [58] is currently available on the φ-meson production density dn/dy (|y| ≤ 0.5) in P bP b collisions at √ s = 2.76 TeV and centrality 5%, and the same occurs for φ-meson production in pP b collisions at √ s = 5.02 Tev for non-single diffraction (NSD) events [59]. [58] on dn/dy, |y| ≤ 0.5, for φ-meson production in P bP b collisions at √ s = 2.76 TeV, compared to the result of corresponding QGSM calculation.…”

“…[58] on dn/dy, |y| ≤ 0.5, for φ-meson production in P bP b collisions at √ s = 2.76 TeV, compared to the result of corresponding QGSM calculation. We also compare the QGSM result with the experimental point on pP b collisions at √ s = 5.02 TeV, for non-single diffraction (NSD) events [59].…”

“…Experimental data QGSM √ s, T eV dn/dy (|y| ≤ 0.5) Pb + Pb 0−5% 2.76 13.8 ± 0.5 ± 1.7 ± 0.1 [58] 13.57 p + Pb NSD 5.02 0.1344 ± 0.005 ± 0.0069 ± 0.0081 [59] 0.14 φ-meson production density dn/dy (|y| ≤ 0.5) in P bP b collisions at √ s = 2.76 Tev and centrality 5%, with the result of corresponding QGSM calculation, the value of dn/dy (|y| ≤ 0.5) = 13.57 is obtained, which agrees with the experimental data, at n max = 37. The calculation at an assimptotically large value of n max (that is, in the absence of inelastic shadowing), yields a value of dn/dy (|y| ≤ 0.5) 20.5.…”