  Molecular dynamics simulations are used to show that strong magnetization
significantly increases the space and time scales associated with interparticle
correlations. The physical mechanism responsible is a channeling effect whereby
particles are confined to move along narrow cylinders with a width
characterized by the gyroradius and a length characterized by the collision
mean free path. The predominant interaction is $180^\circ$ collisions at the
ends of the collision cylinders, resulting in a long-range correlation parallel
to the magnetic field. Its influence is demonstrated via the dependence of the
velocity autocorrelation functions and self-diffusion coefficients on the
domain size and run time in simulations of the one-component plasma. A very
large number of particles, and therefore domain size, must be used to resolve
the long-range correlations, suggesting that the number of charged particles in
the collection must increase in order to constitute a plasma. Correspondingly,
this effect significantly delays the time it takes to reach a diffusive regime,
in which the mean square displacement of particles increases linearly in time.
This result presents challenges for connecting measurements in non-neutral and
ultracold neutral plasma experiments, as well as molecular dynamics
simulations, with fluid transport properties due to their finite size.
