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Swift Observations of GRB 051109B

E. Troja·G. Cusumano·V. LaParola·V. Mangano·T. Mineo
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Abstract

We present Swift observations of GRB 051109B, a soft long burst triggered by the Burst Alert Telescope (BAT). The soft photon index of the prompt emission suggest it is a X-ray Flash (XRF) or, at least, a X-ray Rich (XRR) burst. The X-ray lightcurve displays the canonical shape of many other GRBs, a double b roken power law with a small flare superimposed at ~T_0+1500 s, and its extrapolation to early times smoothly joins with the BAT lightcurve. On the basis of the derived optical to X-ray flux ratio, it cannot be classified as a dark burst.

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E. Troja, G. Cusumano, V. LaParola, V. Mangano, T. Mineo. 2007-01-30. Swift Observations of GRB 051109B. https://doi.org/10.1393/ncb%2Fi2007-10324-8

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