Event-by-Event di-hadron correlations in Pb-Pb 2.76 TeV collisions from the ALICE experiment

Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus–Nucleus Collisions 2012

Timmins, Anthony R.^1

Department of Physics, University of Houston, 617 Science and Research Building 1, Houston, TX 77204, United States^1

关键词: Angular correlations;    Correlation function;    Fourier harmonics;    Hadron correlations;    Impact-parameter;    Initial conditions;    Pb-Pb collisions;    Statistical fluctuations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/446/1/012031/pdf
DOI  :  10.1088/1742-6596/446/1/012031

来源: IOP

【 摘 要 】

The large multiplicities at the LHC may permit flow harmonics to be determined on an event-by-event basis in Pb-Pb collisions. We extract these harmonics from event-by-event di-hadron correlations. Within a fine centrality bin, we find the correlation function varies substantially on an event-by-event basis beyond expectations from statistical fluctuations. This implies large fluctuations in the initial conditions occur for a given impact parameter. Such large fluctuations lead to some events being highly triangular or highly elliptical, where the angular correlation function is completely dominated by the respective second and third Fourier harmonics. We will show unfolded v2distributions for various centralities, and implications for our understanding of the initial conditions.