Observations of GRB afterglows with Russian-Turkish 1.5-m Telescope (RTT150)

GRB 060526

GCN Circ.: 5173, 5177, 5183, 5186, 5189, 5193
The afterglow light curve was measured in detail starting from about 5 h after the GRB and over five ensuing nights. In addition, upper limits were obtained on the rapid variability of the afterglow on the first night of observations and the history of afterglow color variations was measured in detail. In the time interval from 6 to 16h after the burst, the flux gradually decreased approximately as a power law with a slope of -1.14+-0.02. After that, variability was observed on a time scale δt < t and the afterglow started to decay faster. The afterglow color was approximately constant (V-R ≈ 0.5) throughout the observations, despite the flux variability. Variability time scales up to δt ≈ 0.0055 were observed at ΔFν/Fν ≈ 0.3, which violates constraints on the variability of the observed emission from an ultrarelativistic jet obtained by Ioka et al. (2005) for simle models. We suggest to explain this variability by the fact that the shell motion is no longer ultrarelativistic at this time.

Data tables from Khamitov et al. (2007):
Table 1
Table 2


Khamitov et al. Astronomy Letters, 33, 797 (2007), arXiv:0802.1635, The original text in Rissian
see also: Burenin Astronomy Letters, 33, 804 (2007), arXiv:0802.1636, The original text in Rissian





Observations of GRB afterglows with Russian-Turkish 1.5-m Telescope (RTT150)

High Energy Astrophysics Department
Space Research Institute of Russian Academy of Sciences (IKI)