The Panchromatic Afterglow of GW170817: The full uniform dataset,
  modeling, comparison with previous results and implications
  We present the full panchromatic afterglow light curve data of GW170817,
including new radio data as well as archival optical and X-ray data, between
0.5 and 940 days post-merger. By compiling all archival data, and reprocessing
a subset of it, we have evaluated the impact of differences in data processing
or flux determination methods used by different groups, and attempted to
mitigate these differences to provide a more uniform dataset. Simple power-law
fits to the uniform afterglow light curve indicate a $t^{0.86\pm0.04}$ rise, a
$t^{-1.92\pm0.12}$ decline, and a peak occurring at $155\pm4$ days. The
afterglow is optically thin throughout its evolution, consistent with a single
spectral index ($-0.584\pm0.002$) across all epochs. This gives a precise and
updated estimate of the electron power-law index, $p=2.168\pm0.004$. By
studying the diffuse X-ray emission from the host galaxy, we place a
conservative upper limit on the hot ionized ISM density, $<$0.01 cm$^{-3}$,
consistent with previous afterglow studies. Using the late-time afterglow data
we rule out any long-lived neutron star remnant having magnetic field strength
between 10$^{10.4}$ G and 10$^{16}$ G. Our fits to the afterglow data using an
analytical model that includes VLBI proper motion from Mooley et al. (2018),
and a structured jet model that ignores the proper motion, indicates that the
proper motion measurement needs to be considered while seeking an accurate
estimate of the viewing angle.
