The recent excess in the CMS measurements of $eejj$ and $e\nu jj$ channels and the emergence of PeV cosmic 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.

• Received 14 May 2015

DOI:https://doi.org/10.1103/PhysRevD.91.125015