The post-outburst evolution of RW Cep

The great dimming of hypergiant RW Cep at the end of 2022 piqued the interest of both the amateur andprofessional astronomy community (ATel #15800 by Vollmann and Sigismondi). The reported V-filterbrightness dropped to 7.6 mag - down by about 0.9 mag from its previous mean level, comparable to thedimming of Betelgeuse in 2019. The dimming has been attributed to an ongoing mass-loss event.Spectra taken during the event have revealed newly-formed emission components in many absorptionlines. We have monitored RW Cep using the medium-resolution spectrograph attached to the 1.5-mtelescope at Tartu Observatory and complemented that data with high-resolution echelle spectra from theNordic Optical Telescope. With our spectral time series we can follow the variability of RW Cep as it goesthrough the outburst event. We discuss the dynamics of the star’s extensive atmosphere and considerthe post-RSG evolution of RW Cep in the context of yellow hypergiants.