On the VLBI measurement of the Solar System acceleration
  We propose new estimates of the secular aberration drift, mainly due to the
rotation of the Solar System about the Galactic center, based on up-to-date
VLBI observations and and improved method of outlier elimination. We fit
degree-2 vector spherical harmonics to extragalactic radio source proper motion
field derived from geodetic VLBI observations spanning 1979-2013. We pay
particular attention to the outlier elimination procedure to remove outliers
from (i) radio source coordinate time series and (ii) the proper motion sample.
We obtain more accurate values of the Solar system acceleration compared to
those in our previous paper. The acceleration vector is oriented towards the
Galactic center within 7 deg. The component perpendicular to the Galactic plane
is statistically insignificant. We show that an insufficient cleaning of the
data set can lead to strong variations in the dipole amplitude and orientation,
and statistically biased results.
