Search for optical activity of SGR 1806-20
  The region of SGR 1806-20 localization was observed during its gamma-ray activity in 2001. The observations have been performed on the 6-meter telescope of the Special Astrophysical Observatory, using the Panoramic Photometer-Polarimeter (PPP). The search for variability was performed on the $10^{-6}$ - 10 s time scale, and its results were compared to the properties of corresponding x-ray flares. 
G. Beskin, V. Debur, V. Plokhotnichenko, S. Karpov, A. Biryukov, L.   Chmyreva, A. Pozanenko, K. Hurley