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arXiv · 1302.2083

Linear and circular polarimetry observations of GRB afterglows

K. Wiersema
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Abstract

Follow-up observations of large numbers of gamma-ray burst (GRB) afterglows, facilitated by the Swift satellite, have produced a large sample of spectral energy distributions and light curves, from which the basic micro- and macrophysical parameters of afterglows may be derived. However, a number of phenomena have been observed that defy explanation by simple versions of the standard fireball model, leading to a variety of new models. Polarimetry has shown great promise as a diagnosis of afterglow physics, probing the magnetic field properties of the afterglow and geometrical effects (e.g. jet breaks). Unfortunately, high quality polarimetry of a significant sample of afterglows is difficult to acquire, requiring specialised instrumentation and observing modes. In this paper I will review the recent successes in late-time afterglow polarimetry, also showing first results of new instruments and observing campaigns. I will particularly focus on jet breaks.

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K. Wiersema. 2013-02-08. Linear and circular polarimetry observations of GRB afterglows. https://doi.org/10.1051/eas%2F1361029

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