Speaker
Description
Nuclear deformation is a ubiqutous phenomenon for most atomic nuclei, reflecting collective motion induced by interaction between valance nucleons and shell structure. Collisions of deformed nucleus lead to large shape and size fluctuations in the initial state geometry, which after collective expansion, lead to a non-trivial correlation between harmonic flow $v_{n}$ and event-by-event mean transverse momentum $[p_{T}]$. Therefore detailed study of [$p_{T}$] flucutations and $v_2$ -[$p_T$] correlations could probe the quadrupole deformation. In this talk, we present a overview of [$p_T$] fluctuations and $v_{n}$-[$p_T$] correlations for n=2 and 3 from STAR and ATLAS experimental data. Centrality selection, the choice of transverse momentum range and nonflow effect will be discussed. Comparison with state-of-art model calculations is also discussed. This measurement opens up an avenue for studying nuclear structure at a much shorter time scale ($\sim 10^{-23}$s) in heavy-ion collisions.
