Light flavour hadron production in pp collisions at s\sqrt{s} = 13 TeV with ALICE

The ALICE detector has excellent Particle IDentification (PID) capabilities in the central barrel ($\lvert \eta \rvert <$ 0.9). This allows identified hadron production to be measured over a wide transverse momentum ($p_{\rm{T}}$) range, using different sub-detectors and techniques: their specific energy loss (d$E$/d$x$), the velocity determination via time-of-flight measurement, the Cherenkov angle or their characteristic weak decay topology. Results on identified light flavour hadron production at mid-rapidity measured by ALICE in proton-proton collisions at $\sqrt{s}$ = 13 TeV are presented and compared with previous measurements performed at lower energies. The results cover a wide range of particle species including long-lived hadrons, resonances and multi-strange baryons over the $p_{\rm{T}}$ range from 150 MeV/$c$ up to 20 GeV/$c$, depending on the particle species.Comment: 4 pages, 4 figures, Proceedings of Hot Quarks September 12-17, 2016, South Padre Island, Texas, US

Inclusive J/psi production at mid-rapidity in Pb-Pb collisions at sqrt(s_NN)= 5.02 TeV

Charmonium production is a key observable in the study of the properties of the Quark-Gluon Plasma created in ultrarelativistic heavy-ion collisions. The ALICE detector at the LHC provides unique capabilities at mid-rapidity to study charmonium production at low transverse momentum. J/psi mesons can be reconstructed via their dielectron decay channel. This thesis presents the measurement of inclusive J/psi production in Pb-Pb collisions at the center of mass energy of sqrt(s_NN)= 5.02 TeV. Due to the large integrated luminosity collected by ALICE during the second stage of operation of the LHC, the inclusive J/psi nuclear modification factor was measured as a function of centrality and as a function of transverse momentum in different centrality classes. The inclusive J/psi nuclear modification factor exhibits an enhancement towards lower transverse momentum, reaching a value around unity, and a suppression at high transverse momentum where energy-loss mechanisms are dominant. A qualitative description of the measurements is achieved by the models which include a large fraction of J/psi production by recombination. In addition, in peripheral collisions, the observation at mid-rapidity of an excess of J/psi with low transverse momentum (< 150 MeV/c) is presented

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV

Peer reviewe

Identified particle production in pp, p-Pb, and Pb-Pb collisions measured with ALICE at LHC energies

The ALICE detector has excellent Particle IDentification (PID) capabilities in the central barrel (|η| < 0.9). This allows identified hadron production to be measured over a wide transverse momentum (p(T)) range, using different sub-detectors and techniques: their specific energy loss (dE/dx), the time of flight, the Cherenkov angle or their characteristic weak decay topology. Results on identified particle spectra and production yield ratios at mid-rapidity measured by ALICE in different colliding systems (pp, p-Pb and Pb-Pb) are presented and the similarities among them are discussed. For Pb-Pb collisions the nuclear modification factor as a function of p(T) is shown for different collision centralities

ALICE measurement of the J/ψJ/\psi nuclear modification factor at mid-rapidity in Pb–Pb collisions at sNN=\sqrt{{s}_{NN}}= 5.02 TeV

ALICE at the LHC provides unique capabilities to study charmonium production at low transverse momenta ( p T ). At central rapidity, ( |y|<0.8 ), ALICE can reconstruct J/ ψ via their decay into two electrons down to zero p T . Results at mid-rapidity on the inclusive J/ ψ nuclear modification factor RAA as a function of centrality in Pb-Pb collisions at sNN=5.02 TeV and comparisons to lower energies and models are shown. In addition, the yield of the J/ ψ produced with very low p T in the most peripheral collisions and the J/ ψ elliptic flow ( v2 ) are also presented

Inclusive J/ψ production in pp collisions at √s=2.76 TeV

The ALICE Collaboration has measured inclusive J/ψ production in pp collisions at a center-of-mass energy √s=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are Linte=1.1 nb−1 and Lintμ=19.9 nb−1, and the corresponding signal statistics are NJ/ψe+e−=59±14 and NJ/ψμ+μ−=1364±53. We present dσJ/ψ/dy for the two rapidity regions under study and, for the forward-y range, d2σJ/ψ/dydpt in the transverse momentum domain 0<pt<8 GeV/c. The results are compared with previously published results at s=7 TeV and with theoretical calculations