Early Optical Polarization of a Gamma-Ray Burst Afterglow

  title={Early Optical Polarization of a Gamma-Ray Burst Afterglow},
  author={C. G. Mundell and Iain A. Steele and Robert J. Smith and Shiho Kobayashi and A Melandri and C. Guidorzi and A Gomboc and Christopher J. Mottram and David Clarke and A. Monfardini and David Carter and David Bersier},
  pages={1822 - 1824}
We report the optical polarization of a gamma-ray burst (GRB) afterglow, obtained 203 seconds after the initial burst of γ-rays from GRB 060418, using a ring polarimeter on the robotic Liverpool Telescope. Our robust (2σ) upper limit on the percentage of polarization, less than 8%, coincides with the fireball deceleration time at the onset of the afterglow. The combination of the rate of decay of the optical brightness and the low polarization at this critical time constrains standard models of… Expand
Early-time polarized optical light curve of GRB 131030A
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RINGO on the Liverpool Telescope has now measured the optical polarization of GRB 060418 (where a 2 sigma upper limit of P<8% was determined) and GRB 090102 (when a detection of P = 10 +/-1 % wasExpand
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With the successful launch of the Swift Gamma-Ray Burst Explorer, a rich trove of early X-ray afterglow data has been collected by its onboard X-Ray Telescope (XRT). Some interesting features areExpand