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arXiv · 1505.00028

The Leptoquark Implication from the CMS and IceCube Experiments

Abstract

The recent excess in the CMS measurements of $eejj$ and $e\nu jj$ channels and the emergence of PeV comsic neutrino events at the IceCube experiment share an intriguing implication for a leptoquark with a 600-650 GeV mass. We investigate the CMS constraints on the flavor structure of a scenario with the minimal leptoquark Yukawa couplings and correlate such a scenario to the resonant enhancement in the very high energy shower event rates at the IceCube. We find for a single leptoquark, the CMS signals require large couplings to the third generation leptons. This leads to an enhancement in the $\nu_\tau$-nucleon scattering cross-section and subsequently more $\nu_\tau$ events at PeV energies. However, a visible enhancement above the Standard Model scattering would require a leptoquark Yukawa coupling larger than one that can be easily tested at the upcoming LHC runs.

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Bhaskar Dutta, Yu Gao, Tianjun Li, Carsten Rott, Louis E. Strigari. 2015-04-30. The Leptoquark Implication from the CMS and IceCube Experiments. https://doi.org/10.1103/physrevd.91.125015

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