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arXiv · 1908.09614

Constraints on Lorentz invariance violation using HAWC observations above 100 TeV

H. Martínez-Huerta·S. Marinelli·J. T. Linnemann·J. Lundeen
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Abstract

Due to the high energies and long distances involved, astrophysical observations provide a unique opportunity to test possible signatures of Lorentz Invariance Violation (LIV). Superluminal LIV enables the decay of photons at high energy over relatively short distances, giving astrophysical spectra which have a hard cutoff above this energy. The High Altitude Water Cherenkov (HAWC) observatory is the most sensitive currently-operating gamma-ray observatory in the world above 10 TeV. Together with the recent development of an energy-reconstruction algorithm for HAWC using an artificial neural network, HAWC can make detailed measurements of gamma-ray energies above 100 TeV. With these observations, HAWC can limit the LIV energy scale greater than $10^{31}$ eV, over 800 times the Planck energy scale. This limit on LIV is over 60 times more constraining than the best previous value for $\rm E_{LIV}^{(1)}$.

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H. Martínez-Huerta, S. Marinelli, J. T. Linnemann, J. Lundeen. 2019-08-26. Constraints on Lorentz invariance violation using HAWC observations above 100 TeV. https://arxiv.org/abs/1908.09614

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