Disentangling the radio emission of the supernova remnant W51C
  We simulate the evolution of supernova remnant (SNR) W51C. The simulation
shows the existence of a new northeast edge. We present magnetic field
structure of the W51 complex (SNR W51C and two HII regions W51A/B) by employing
the 11 cm survey data of Effelsberg. This new edge is identified and overlaps
with W51A along the line of sight, which gives a new angular diameter of about
37' for the quasi-circular remnant. In addition, we assemble the OH spectral
lines (1612/1665/1720 MHz) towards the complex by employing the newly released
THOR (The HI OH Recombination line survey of Milky Way) data. We find that the
known 1720 MHz OH maser in the W51B/C overlap area is located away from the
detected 1612/1665MHz absorption region. The latter is sitting at the peak of
the HII region G49.2-0.35 within W51B.
