  The dynamics and the structure of the solar corona are determined by its
magnetic field. Measuring coronal magnetic fields is, however, extremely hard.
The polarization of low-frequency radio emissions has long been recognized as
one of the few effective observational probes of magnetic fields in the mid and
high corona. However, the extreme intrinsic variability of this emission, the
limited ability of most of the available existing instrumentation (until
recently) to capture it, and the technical challenges involved have all
contributed to its use being severely limited. The high dynamic-range
spectropolarimetric snapshot imaging capability that is needed for radio
coronal magnetography is now within reach. This has been enabled by the
confluence of data from the Murchison Widefield Array (MWA), a Square Kilometre
Array (SKA) precursor, and our unsupervised and robust polarization calibration
and imaging software pipeline dedicated to the Sun-Polarimetry using the
Automated Imaging Routine for Compact Arrays of the Radio Sun (P-AIRCARS).
Here, we present the architecture and implementation details of P-AIRCARS.
Although the present implementation of P-AIRCARS is tuned to the MWA, the
algorithm itself can easily be adapted for future arrays, such as SKA1-Low. We
hope and expect that P-AIRCARS will enable exciting new science with
instruments like the MWA, and that it will encourage the wider use of radio
imaging in the larger solar physics community.
