What can the event transverse energy distribution tell us about the longitudinal flow?

20 May 2014, 16:30
spectrum (darmstadtium)



Board: H-41
Poster Collective Dynamics Poster session


Bin Zhang (Arkansas State University)


Transverse energy is an important characteristic of relativistic heavy ion collisions aiming at creating conditions similar to those existed in the early Universe. The hot and dense matter produced immediately after the collision of a nucleus going in the longitudinal direction and the other in the opposite direction can be considered as being composed of transverse fluid slices undergoing longitudinal expansion following the two receding nuclei. In the nucleon-nucleon center-of-mass frame, a slice that is closer to a nucleus has a bigger longitudinal speed. Transverse energy is longitudinally boost invariant and therefore directly reflects the condition of the local rest frame (slice) irrespective of its longitudinal flow speed. It is sensitive to the longitudinal work between adjacent slices and thus carries information about the evolution of the hot and dense matter produced in heavy ion collisions. We show that the work distribution of an expanding extreme relativistic gas is a gamma distribution with a different shape parameter as compared with its non-relativistic counterpart. This implies that the shape of the transverse energy distribution in relativistic heavy ion collisions depends on the particle contents during the evolution of the hot and dense matter. Therefore, transverse energy fluctuations provide additional insights into the Quark-Gluon Plasma produced in these collisions.

Primary author

Bin Zhang (Arkansas State University)


Jay Mayfield (Arkansas State University)

Presentation Materials