VLBI polarimetry of the high rotation measure source 3C 119 at 8.4 GHz

We have mapped the distribution of the rotation measure of the CSS source 3 C 119 on milliarcsecond scales using VLBA observations obtained at three wi dely-separated frequencies in the available 8.4-GHz band. The resulting ima ges at frequencies 8.16, 8.52, and 8.86 GHz demonstrate that the material a ssociated with the large integrated rotation measure of the source is conce ntrated near the brightest jet component C. There is a large, smooth gradie nt of the rotation measure in this component of 2300 rad/m(2)/mas, with the largest rotation measure at the leading edge. This supports the idea that C is associated with a collision between the VLBI jet and a dense intergala ctic cloud. The magnetic field in C is aligned with the Row into C from the northeast, and swings through similar to 45 degrees so that it remains ali gned with the inferred flow toward the emission further down the jet, nearl y directly to the south.