Short paper: Photometric and spectroscopic observations of the outburst of the symbiotic star AG Draconis between 2016 March and June

The symbiotic star AG Dra is a binary system with orbital period 550 days consisting of a hot star, probably a white dwarf, and a cool K-type red giant. These stars are surrounded by a circumbinary nebula generated by a wind from the giant star. This wind is partially ionised by radiation from the hot star, creating strong emission lines in the optical spectrum. During quiescence the hot star sustains a high surface temperature by nuclear burning hydrogen-rich material accreted from the stellar wind onto its surface. … (continued…)

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