A revised lens time delay for JVAS B0218+357 from a reanalysis of VLA
  monitoring data
  We have reanalysed the 1996/1997 VLA monitoring data of the gravitational
lens system JVAS B0218+357 to produce improved total flux density and
polarization variability curves at 15, 8.4 and 5 GHz. This has been done using
improved calibration techniques, accurate subtraction of the emission from the
Einstein ring and careful correction of various systematic effects, especially
an offset in polarization position angle that is hour-angle dependent. The
variations in total and polarized flux density give the best constraints and we
determine a combined delay estimate of $11.3 \pm 0.2$ d (1$\sigma$). This is
consistent with the $\gamma$-ray value recently derived using the Fermi
Gamma-ray Space Telescope and thus we find no evidence for a positional shift
between the radio and $\gamma$-ray emitting regions. Combined with the
previously published lens model found using LensClean, the new delay gives a
value for the Hubble constant of $H_0 = 72.9 \pm 2.6$ km s$^{-1}$ Mpc$^{-1}$
(1$\sigma$).
