New Mechanism for Quark Energy Loss

We show that a heavy quark moving sufficiently fast through a quark-gluon plasma may lose energy by Cherenkov-radiating mesons. We demonstrate that this takes place in all strongly coupled, large-$N_c$ plasmas with a gravity dual. The energy loss is exactly calculable in these models despite being an $\mathcal{O}(1/N_c)$ effect. We discuss implications for heavy-ion collision experiments.

Figure 1

$D$-branes and open string in a BH geometry.

Figure 2

DR for the transverse (black, continuous curve) and longitudinal (red, dashed curve) modes of a heavy vector meson with $v_{\lim }=0.35$ in the $D3/D7$ system. The blue, continuous straight line corresponds to $\omega =vq$ with $v_{\lim }<v<1$.

Figure 3

Effective quark-meson coupling.

Figure 4

Energy loss into ${\mathcal{A}}_{(n=0)}$ for an embedding with $R(\infty )=1.32$. The continuous curves correspond to $r_0=0.86$, 0.97, 1.10, 1.25, 1.45. The dotted curve is defined by the end points of the constant-$r_0$ curves.