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arXiv · 1710.08222

Multi-Epoch Radio Imaging of gamma-ray Nova V959 Mon

F. Healy·T. J. O Brien·R. Beswick·A. Avison·M. K. Argo
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Abstract

V959 Mon (Nova Mon 2012) was first detected by the Fermi Large Area Telescope in June 2012, as a transient gamma-ray source. Subsequent optical observations showed that this gamma-ray emission was due to a classical nova explosion. Multi-frequency observations of V959 Mon with the VLA between June and September 2012 revealed dramatic brightening, and a spectrum that steepened with increasing frequency. High resolution radio images of V959 Mon using e-MERLIN are presented here, at six epochs between September 2012 and February 2014 which show morphological evolution of the source. While early e-MERLIN observations of V959 Mon show an east-west elonga- tion in the ejecta morphology, subsequent observations suggest that the ejecta become elongated in the north-south direction. Our high-resolution observations of this sur- prising evolution in the structure of V959 Mon can assist us in further understanding the behaviour and morphology of nova ejecta.

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F. Healy, T. J. O Brien, R. Beswick, A. Avison, M. K. Argo. 2017-10-23. Multi-Epoch Radio Imaging of gamma-ray Nova V959 Mon. https://doi.org/10.1093/mnras%2Fstx1087

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