Tracing Magnetic Field with Synchrotron Polarization Gradients:
  Parameter Study
  We employ synthetic observations obtained with MHD simulations to study how
to trace the distribution of turbulent magnetic fields using the synchrotron
polarization gradient techniques suggested by Lazarian \& Yuen (2018). Both
synchrotron polarization gradients and its derivative gradients with regard to
the squared wavelength $\lambda^2$ are used to explore the probing ability of
the technique in magnetic fields from sub- to super-Alfv{\'e}nic turbulence. We
focus on studies that involve multi-frequency measurements in the presence of
strong Faraday rotation and show the ways of how to recover the projected mean
magnetic fields in the plane of the sky and the local magnetic fields within a
tomographic slice. We conclude that the new techniques can successfully
reconstruct the 3D magnetic field within our Milky Way and other galaxies. This
paper opens an avenue for applying our new techniques to a large number of data
cubes such as those from the Low Frequency Array for Radio astronomy and the
Square Kilometer Array.
