GRB 120711A: an intense INTEGRAL burst with long-lasting soft gamma-ray emission and a powerful optical flash

A. Martin-Carrillo, L. Hanlon, M. Topinka, A. P. LaCluyze, V. Savchenko, D. A. Kann, A. S. Trotter, S. Covino, Thomas Christian Krühler, J. Greiner, S. McGlynn, D. Murphy, P. Tisdall, S. Meehan, C. Wade, B. McBreen, D. E. Reichart, D. Fugazza, J. B. Haislip, A. RossiP. Schady, J. Elliott, S. Klose