Reconstruction with velocities
  Reconstruction is becoming a crucial procedure of galaxy clustering analysis
for future spectroscopic redshift surveys to obtain subpercent level
measurement of the baryon acoustic oscillation scale. Most reconstruction
algorithms rely on an estimation of the displacement field from the observed
galaxy distribution. However, the displacement reconstruction degrades near the
survey boundary due to incomplete data and the boundary effects extend to
$\sim100\,\mathrm{Mpc}/h$ within the interior of the survey volume. We study
the possibility of using radial velocities measured from the cosmic microwave
background observation through the kinematic Sunyaev-Zel'dovich effect to
improve performance near the boundary. We find that the boundary effect can be
reduced to $\sim30-40\,\mathrm{Mpc}/h$ with the velocity information from
Simons Observatory. This is especially helpful for dense low redshift surveys
where the volume is relatively small and a large fraction of total volume is
affected by the boundary.
