Galacto-forensic of LMC's orbital history as a probe for the dark matter
  potential in the outskirt of the Galaxy
  The 3D observed velocities of the Large and Small Magellanic Clouds(LMC and
SMC) provide an opportunity to probe the Galactic potential in the outskirt of
the Galactic halo. Based on a canonical NFW model of the Galactic potential,
Besla et al.(2007) reconstructed LMC and SMC's orbits and suggested that they
are currently on their first perigalacticon passage about the Galaxy. Motivated
by several recent revisions of the Sun's motion around the Galactic center, we
re-examine the LMC's orbital history and show that it depends sensitively on
the dark-matter's mass distribution beyond its present Galactic distance. We
utilize results of numerical simulations to consider a range of possible
structural and evolutionary models for the Galactic potentials. We find that
within the theoretical and observational uncertainties, it is possible for the
LMC to have had multiple perigalacticon passages on the Hubble time scale,
especially if the Galactic circular velocity at the location of the Sun is
greater than $\sim 228$km s$^{-1}$. Based on these models, a more accurate
determination of the LMC's motion may be used to determine the dark matter
distribution in the outskirt of the Galactic halo.
