Speaker
Stefan Heckel
(Johann-Wolfgang-Goethe Univ.)
Description
Non-statistical event-by-event fluctuations of the mean transverse momentum of charged particles in pp and Pb--Pb collisions are studied using the ALICE experiment at the LHC. The analysis is performed at $|\eta| < 0.8$ and $0.15 < p_{T} < 2 $~GeV/c. Multiplicity dependent results are obtained for pp collisions at $\sqrt{s}$~=~0.9, 2.76 and 7~TeV. Pb--Pb collisions at $\sqrt{s_{NN}}$~=~2.76~TeV are analysed in intervals of multiplicity and centrality, the latter in bins of 5\%.
Little collision energy dependence is observed in pp collisions. The data indicate a common scaling behaviour with event multiplicity from pp to semi-central Pb--Pb collisions. In central Pb--Pb collisions, the results deviate from this trend, exhibiting a significant reduction of the fluctuation strength. The results are compared to measurements in Au--Au collisions at lower collision energies and to Monte Carlo simulations with PYTHIA and HIJING.
Author
Stefan Heckel
(Johann-Wolfgang-Goethe Univ.)