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تسجيل مستخدم جديدExploring the canonical behaviour of long gamma-ray bursts using an intrinsic multi-wavelength afterglow correlation
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In this paper we further investigate the relationship, reported by Oates et al., 2012, between the optical/UV afterglow luminosity (measured at restframe 200s) and average afterglow decay rate (measured from restframe 200s onwards) of long duration Gamma-ray Bursts (GRBs). We extend the analysis by examining the X-ray light curves, finding a consistent correlation. We therefore explore how the parameters of these correlations relate to the prompt emission phase and, using a Monte Carlo simulation, explore whether these correlations are consistent with predictions of the standard afterglow model. We find significant correlations between: $rm log;L_{O,200rm{s}}$ and $rm log;L_{X,200rm{s}}$; $alpha_{O,>200rm{s}}$ and $alpha_{X,>200rm{s}}$, consistent with simulations. The model also predicts relationships between $rm log;E_{iso}$ and $rm log;L_{200rm{s}}$, however, while we find such relationships in the observed sample, the slope of the linear regression is shallower than that simulated and inconsistent at $gtrsim 3sigma$. Simulations also do not agree with correlations observed between $rm log;L_{200rm{s}}$ and $alpha_{>200rm{s}}$, or $rm log;E_{iso}$ and $alpha_{>200rm{s}}$. Overall, these observed correlations are consistent with a common underlying physical mechanism producing GRBs and their afterglows regardless of their detailed temporal behaviour. However, a basic afterglow model has difficulty explaining all the observed correlations. This leads us to briefly discuss alternative more complex models.
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