A variable star in the vicinity of the soft -ray repeater 1806 - 20

The APM facility in Cambridge has been used to search archive UK Schmidt Telescope photographic plates for an optical counterpart of SGR 1806-20. The search has revealed a late-type variable star just outside the revised 3 σ error box. A low-resolution spectrum of the star suggests that it is almost undoubtedly an M9 Mira