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arXiv · hep-ph/0010152

Energy-momentum uncertainties as possible origin of threshold anomalies in UHECR and TeV-gamma ray events

Y. Jack Ng·D. -S. Lee·M. C. Oh·H. van Dam
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Abstract

A threshold anomaly refers to a theoretically expected energy threshold that is not observed experimentally. Here we offer an explanation of the threshold anomalies encountered in the ultra-high energy cosmic ray events and the TeV-gamma ray events, by arguing that energy-momentum uncertainties due to quantum gravity, too small to be detected in low-energy regime, can affect particle kinematics so as to raise or even eliminate the energy thresholds. A possible modification of the energy-momentum dispersion relation, giving rise to time-of-flight differences between photons of different energies from gamma ray bursts, is also discussed.

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Y. Jack Ng, D. -S. Lee, M. C. Oh, H. van Dam. 2000-10-24. Energy-momentum uncertainties as possible origin of threshold anomalies in UHECR and TeV-gamma ray events. https://doi.org/10.1016/s0370-2693(01)00436-1

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