We present the charged-particle pseudorapidity density in PbâPb collisions at sNN=5.02 TeV in centrality classes measured by ALICE. The measurement covers a wide pseudorapidity range from â3.5 to 5, which is sufficient for reliable estimates of the total number of charged particles produced in the collisions. For the most central (0â5%) collisions we find 21400Â±1300, while for the most peripheral (80â90%) we find 230Â±38. This corresponds to an increase of (27Â±4)% over the results at sNN=2.76 TeV previously reported by ALICE. The energy dependence of the total number of charged particles produced in heavy-ion collisions is found to obey a modified power-law like behaviour. The charged-particle pseudorapidity density of the most central collisions is compared to model calculations â none of which fully describes the measured distribution. We also present an estimate of the rapidity density of charged particles. The width of that distribution is found to exhibit a remarkable proportionality to the beam rapidity, independent of the collision energy from the top SPS to LHC energies.
|Titolo:||Centrality dependence of the pseudorapidity density distribution for charged particles in PbâPb collisions at sNN=5.02Â TeV|
|Data di pubblicazione:||2017|
|Appare nelle tipologie:||1.1 Articolo in rivista|