Mapping UHECRs deflections through the turbulent galactic magnetic field
  with the latest RM data
  We study the influence of the random part of the Galactic magnetic field on
the propagation of ultra high-energy cosmic rays. Within very mild
approximations about the properties of the electron density fluctuations in the
Galaxy we are able to derive a clear and direct relation between the observed
variance of rotation measures and the predicted cosmic ray deflections.
Remarkably, this is obtained bypassing entirely the detailed knowledge of the
magnetic properties of the turbulent plasma. Depending on the parameters of the
electron density spectrum, we can either directly estimate the expected
deflection, or constrain it from above. Thanks to the latest observational data
on rotation measures, we build a direction-dependent map of such deflections.
We find that over most of the sky the random deflections of 40 EeV protons do
not exceed 1 to 2 degrees, and can be as large as 5 degrees close to the
Galactic plane.
