Disentangling the radio emission of the supernova remnant W51C

TL;DR

This study combines simulations and multi-wavelength observations to analyze the structure, magnetic field, and spectral line features of supernova remnant W51C, revealing a new edge and detailed OH maser distributions.

Contribution

It introduces a new simulation-based detection of a northeast edge and provides detailed magnetic and spectral line analysis of W51C and surrounding regions.

Findings

Discovery of a new northeast edge in W51C

Identification of magnetic field structure in W51 complex

Localization of OH maser emissions relative to HII regions

Abstract

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.