Detailed analyses of GRB 060105 X-ray afterglow observed by Suzaku

GRB 060105 was detected with the BAT instrument on-board Swift. The Suzaku follow-up observation started just 5.3 hours after the trigger with the XIS and HXD instruments. The XIS detected an uncatalogued fading source and its position was consistent with that previously reported by Swift XRT. We performed the spectral analyses using the data derived from Suzaku XIS and Swift XRT, and found that the spectrum of X-ray afterglow was well reproduced by the absorbed power law model. The best-fit spectral index and absorption are β = 2.15 ± 0.03 and N Η = (3.74 ± 0.03) x 10 21 cm -2 , respectively. The observed decay'curve by Suzaku XIS is fully consistent with the Swift XRT result. The Suzaku and Swift observations imply the possibility of the jet break at t = 3500s, and the brightening of afterglow around t = 40000s likely due to the refreshed shock. We see neither significant spectral evolution during the decay, nor evidence of emission line feature.