  Structures observed in debris disks may be caused by gravitational
interaction with planetary or stellar companions. These perturbed disks are
often thought to indicate the presence of planets and offer insights into the
properties of both the disk and the perturbing planets. Gaps in debris disks
may indicate a planet physically present within the gap, but such gaps can also
occur away from the planet's orbit at mean-motion resonances (MMRs), and this
is the focus of our interest here. We extend our study of planet-disk
interaction through MMRs, presented in an earlier paper, to systems in which
the perturbing planet has moderate orbital eccentricity, a common occurrence in
exoplanetary systems. In particular, a new result is that the 3:1 MMR becomes
distinct at higher eccentricity, while its effects are absent for circular
planetary orbits. We also only consider gravitational interaction with a
planetary body of at least 1 Jupiter mass. Our earlier work shows that even a 1
Earth mass planet can theoretically open an MMR gap; however, given the narrow
gap that can be opened by a low-mass planet, its observability would be
questionable. We find that the widths, locations, and shapes of two prominent
structures, the 2:1 and 3:1 MMRs, could be used to determine the mass,
semimajor axis, and eccentricity of the planetary perturber and present an
algorithm for doing so. These MMR structures can be used to narrow the position
and even determine the planetary properties (such as mass) of any inferred but
as-yet-unseen planets within a debris disk. We also briefly discuss the
implications of eccentric disks on brightness asymmetries and their dependence
on the wavelengths with which these disks are observed.
