  The Coriolis force is a significant source of systematic phase errors and
dephasing in atom interferometry and is often compensated by counter-rotating
the interferometry laser beam against Earth's rotation. We present a novel
method for performing Coriolis force compensation for long-baseline atom
interferometry which mitigates atom-beam misalignment due to beam rotation, an
effect which is magnified by the long lever arm of the baseline length. The
method involves adjustment of the angle of the interferometer beam prior to a
magnifying telescope, enabling the beam to pivot around a tunable position
along the interferometer baseline. By tuning the initial atom kinematics, and
adjusting the angle with which the interferometer beam pivots about this point,
we can ensure that the atoms align with the center of the beam during the atom
optics laser pulses. This approach will be used in the MAGIS-100 atom
interferometer and could also be applied to other long-baseline atom
interferometers. An additional challenge associated with long baseline
interferometry is that since long-baseline atom interferometers are often
located outside of typical laboratory environments, facilities constraints may
require lasers to be housed in a climate-controlled room a significant distance
away from the main experiment. Nonlinear effects in optical fibers restrict the
use of fiber-based transport of the high-power interferometry beam from the
laser room to the experiment. We present the design of and prototype data from
a laser transport system for MAGIS-100 that maintains robustness against
alignment drifts despite the absence of a long fiber.
