Source breakup dynamics in Au+Au Collisions at sqrt(s_NN)=200 GeV via three-dimensional two-pion source imaging

TL;DR

This study uses 3D two-pion correlation imaging in Au+Au collisions at 200 GeV to reveal detailed source dynamics, including long-range tails and emission times, supporting hydrodynamical models of source evolution.

Contribution

It provides the first detailed 3D imaging of the pion emission source in heavy-ion collisions, revealing long-range tails and emission time characteristics consistent with hydrodynamical source evolution.

Findings

Long-range tails in the emission source function.

Proper breakup time ~9 fm/c and emission duration ~2 fm/c.

Evidence of outside-in 'burning' of the source.

Abstract

A three-dimensional (3D) correlation function obtained from mid-rapidity, low pT pion pairs in central Au+Au collisions at sqrt(s_NN)=200 GeV is studied. The extracted model-independent source function indicates a long range tail in the directions of the pion pair transverse momentum (out) and the beam (long). Model comparisons to these distensions indicate a proper breakup time \tau_0 ~ 9 fm/c and a mean proper emission duration \Delta\tau ~ 2 fm/c, leading to sizable emission time differences (<|\Delta \tau_LCM |> ~ 12 fm/c), partly due to resonance decays. They also suggest an outside-in "burning" of the emission source reminiscent of many hydrodynamical models.