Constraints on Leptoquark Models from IceCube Data

Leptoquarks in the mass range of 500-1000 GeV can be resonantly produced in significant numbers by PeV neutrino interacting with nuclei at IceCube. We compute the event rates of leptoquark production and decay events and use the 3-year IceCube data for PeV energy events to find the allowed range of the leptoquarks mass and coupling parameter space. We use a low-scale quark lepton unification model based on the $SU(4)_C \otimes SU(2)_L\otimes U(1)_R$ gauge group where leptoquark couplings which give rise to proton decay are forbidden by the symmetry. We constrain the parameters of this model and point out signals of leptoquarks in this model which may be seen in PeV energy IceCube events in the future.