New insights on supernova remnants and HII regions in M82

D. Williams-Baldwin; G. Lucatelli; T. W. B. Muxlow; R. J. Beswick; S. W. Shungube; R. Lumpkin-Robbins; M. K. Argo; D. M. Fenech; N. Kimani; J. Radcliffe

arXiv · 2504.17500

New insights on supernova remnants and HII regions in M82

D. Williams-Baldwin·G. Lucatelli·T. W. B. Muxlow·R. J. Beswick·S. W. Shungube·R. Lumpkin-Robbins·M. K. Argo·D. M. Fenech·N. Kimani·J. Radcliffe

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Abstract

The nearby (d=3.6 Mpc) starburst galaxy M82 has been studied for several decades by very long baseline interferometry (VLBI) networks such as e-MERLIN and the European VLBI Network (EVN). The numerous supernova remnants (SNRs), HII regions and other exotic transients make it a perfect laboratory for studying stellar evolution and the interstellar medium (ISM). Its proximity provides a linear resolution of 17 pc/arcsec, enabling decadal-time-scale variability and morphology studies of the tens of compact radio sources. In this proceedings, we describe new techniques developed in the last ten years that provide deeper, more robust imaging, enable in-band spectral index mapping, and allow wider fields of view to be imaged to find new radio sources.

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D. Williams-Baldwin, G. Lucatelli, T. W. B. Muxlow, R. J. Beswick, S. W. Shungube, R. Lumpkin-Robbins, M. K. Argo, D. M. Fenech, N. Kimani, J. Radcliffe. 2025-04-24. New insights on supernova remnants and HII regions in M82. https://arxiv.org/abs/2504.17500

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