Charm quarks are more hydrodynamic than light quarks in final-state elliptic flow

Understand

We study the charm quark elliptic flow ($v_{2}$) in heavy ion as well as small system collisions by tracking the evolution history of quarks of different flavors within a multi-phase transport model.

• The charm quark $v_{2}$ is studied as a function of the number of collisions the charm quark suffers with other quarks and then compared to the $v_{2}$ of lighter quarks.
• We find that the common escape mechanism is at work for both the charm and light quark $v_{2}$.
• However, contrary to the naive expectation, the hydrodynamics-type flow is found to contribute more to the final state charm $v_{2}$ than light quark $v_{2}$.