Abstract
The production of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons in proton-proton (pp) and lead-lead (Pb-Pb) collisions at $\sqrt{s_\mathrm{NN}} =$ 2.76 TeV has been analyzed using a high luminosity data sample accumulated in 2011 with the ALICE detector at the Large Hadron Collider (LHC). Transverse momentum ($p_{\mathrm{T}}$) spectra have been measured for K$^{*}(892)^{0}$ and $\phi(1020)$ mesons via their hadronic decay channels for $p_{\mathrm{T}}$ up to 20 GeV/$c$. The measurements in pp collisions have been compared to model calculations and used to determine the nuclear modification factor and particle ratios. The K$^{*}(892)^{0}$/K ratio exhibits significant reduction from pp to central Pb-Pb collisions, consistent with the suppression of the K$^{*}(892)^{0}$ yield at low $p_{\mathrm{T}}$ due to rescattering of its decay products in the hadronic phase. In central Pb-Pb collisions the $p_{\mathrm{T}}$ dependent $\phi(1020)/\pi$ and K$^{*}(892)^{0}$/$\pi$ ratios show an enhancement over pp collisions for $p_{\mathrm{T}}$ $\sim$3 GeV/$c$, consistent with previous observations of strong radial flow. At high $p_{\mathrm{T}}$, particle ratios in Pb-Pb collisions are similar to those measured in pp collisions. In central Pb-Pb collisions, the production of K$^{*}(892)^{0}$ and $\phi(1020)$ mesons is suppressed for $p_{\mathrm{T}}> 8$ GeV/$c$. This suppression is similar to that of charged pions, kaons and protons, indicating that the suppression does not depend on particle mass or flavor in the light quark sector.
Highlights
It has been established that hot and dense strongly interacting matter, often described as a strongly coupled quark-gluon plasma [1,2,3], is produced in heavy-ion collisions at ultrarelativistic energies
The pT spectra in this paper are combinations of results obtained with particle identification (PID) at low momentum and results obtained without PID for higher pT in both pp and Pb-Pb collisions
Different PYTHIA tunes were developed by different groups through extensive comparison of Monte Carlo distributions with the minimum bias data from various experiments
Summary
It has been established that hot and dense strongly interacting matter, often described as a strongly coupled quark-gluon plasma (sQGP) [1,2,3], is produced in heavy-ion collisions at ultrarelativistic energies The properties of this matter are characterized, among other features, by the energy loss of partons traversing the dense color-charged medium, which manifests itself via suppression of hadrons with high transverse momentum in central Pb-Pb collisions. GeV/c (0.5 < pT < GeV/c) in Pb-Pb collisions in six [seven] centrality classes for K∗(892)0 [φ(1020)] This new data set allowed the measurement of K∗(892)0 in finer centrality intervals in central and semicentral Pb-Pb collisions to study hadron production mechanisms at low, intermediate, and high pT.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
