  We use the holographic dual of a finite-temperature, strongly-coupled, gauge
theory with a small number of flavors of massive fundamental quarks to study
meson excitations and deep inelastic scattering (DIS) in the low-temperature
phase, where the mesons are stable. We show that a high-energy flavor current
with nearly light-like kinematics disappears into the plasma by resonantly
producing mesons in highly excited states. This mechanism generates the same
DIS structure functions as in the high temperature phase, where mesons are
unstable and the current disappears through medium-induced parton branching. To
establish this picture, we derive analytic results for the meson spectrum,
which are exact in the case of light-like mesons and which corroborate and
complete previous, mostly numerical, studies in the literature. We find that
the meson levels are very finely spaced near the light-cone, so that the
current can always decay, without a fine-tuning of its kinematics.
