Wray 15-811: An unusual runaway star

Abstract

We investigate Wray 15-811, a poorly studied object of controversial nature. We present for the first time spectroscopic observations (at low, medium, and high resolution), together with deep narrow-band images. These original data are combined with data from public surveys, to infer the nature of this object. We conclude that Wray 15-811 is indeed a carbon star with an optical bow-shock nebula associated. Its spectrum displays a split H emission, and its SED indicates the presence of silicates features. The light curve is similar to the expected for a Mira variable with a 504-day period. Its proper motion is compatible with that of a runaway star, consistent with the presence of the observed bow-shock nebula.