Jet-medium interaction and conformal relativistic fluid dynamics

A formalism to study the mode-by-mode response to the energy deposition of external hard partons propagating in a relativistic fluid is developed, based on a semianalytical solution of conformal fluid dynamics. The soft-particle production resulting from the jet-medium interaction is calculated, and the recoil of the viscous medium is studied for different orientations of the relativistic jets and for different values of the specific shear viscosity $\eta /s$.

Figure 1

Three events with dijets considered in this work. Solid arrows indicate jet partons generating the near-side (leading) peak of the observed spectrum, while dashed arrows are those generating the away-side (subleading) peak.

Figure 2

Medium excitations on top of expanding viscous systems with $\eta /s=1/4\pi$ (upper rows) and $\eta /s=2/4\pi$ (lower rows) with respect to the near-side jet parton of event I, plotted in terms of energy density $\delta e$ (left panels) and energy flux $\delta T^{0\parallel }$ (right panels), at $\tau =6.0\mathrm{fm}/\mathrm{c}$. The color coding reflects units of $\mathrm{GeV}/{\mathrm{fm}}^3$.

Figure 3

First row: pion number density generated from the medium response to jet partons as a function of azimuthal angle. The near- and away-side number densities are shown separately, as well as their sum (solid line). Second row: transverse energy of the induced pions from the medium response to a dijet in a weakly coupled system. Third row: transverse energy of the induced pions from jet-medium interaction for a strongly coupled system. See the main text for more details. A lower cut of $p_T\ge 1$ GeV has been applied in these plots.