Possibility of Ultra High-Energy Cosmic Rays from the Giant Flare in SGR   1806-20
  On 2004 December 27, a giant flare from the soft gamma repeater 1806$-$20 was observed. The radiation mechanism of the initial peak of the flare would be controversial. In this letter we point out that very high-energy cosmic rays would be produced in the case that the flare was caused by internal shocks, as is usually considered for gamma-ray bursts. The highest energy of cosmic rays can reach $10^{19}$ eV, if the Lorentz factor of the shocks is sufficiently high. Future observations of cosmic rays will inform us about the mechanism of the giant flare. 
Katsuaki Asano, Ryo Yamazaki, and Naoshi Sugiyama