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arXiv · 1401.8178

The CTA Sensitivity to Lorentz-Violating Effects on the Gamma-Ray Horizon

Malcolm Fairbairn·Albin Nilsson·John Ellis·Jim Hinton·Richard White
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Abstract

The arrival of TeV-energy photons from distant galaxies is expected to be affected by their QED interaction with intergalactic radiation fields through electron-positron pair production. In theories where high-energy photons violate Lorentz symmetry, the kinematics of the process $γ+ γ\rightarrow e^+ + e^-$ is altered and the cross-section suppressed. Consequently, one would expect more of the highest-energy photons to arrive if QED is modified by Lorentz violation than if it is not. We estimate the sensitivity of Cherenkov Telescope Array (CTA) to changes in the $γ$-ray horizon of the Universe due to Lorentz violation, and find that it should be competitive with other leading constraints.

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Malcolm Fairbairn, Albin Nilsson, John Ellis, Jim Hinton, Richard White. 2014-06-30. The CTA Sensitivity to Lorentz-Violating Effects on the Gamma-Ray Horizon. https://doi.org/10.1088/1475-7516%2F2014%2F06%2F005

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