Rossi, Andrea; Kann, David Alexander; Schulze, Steve; Ferrero, Patrizia; Filgas, Robert; Klose, Sylvio; Clemens, Christian; Yoldaş, Aybüke Küpcü; Krühler, Thomas; Yoldaş, Abdullah et al.
GAMMA-RAY BURSTS 2007: Proceedings of the Santa Fe Conference. AIP Conference Proceedings, Volume 1000, pp. 327-330 (2008).
The nature of the dark bursts is still not fully understood. Here, we report on some of our recent studies on Swift dark bursts. Thereby, we pay particular attention to GRB 050717, for which we obtained a deep imaging of the X-ray error circle with the newly commissioned GROND camera mounted at the 2.2 m telescope on La Silla.