[math-fun] ice cube finds high energy neutrinos

http://www.cbpf.br/~icrc2013/papers/icrc2013-0650.pdf the highest energy neutrino they detected was claimed to be 1200 TeV, which is pretty absurd (equivalent to about 1.3 million proton masses). This seems far greater than could be produced in any nuclear reaction, and neutrinos since neutral cannot be accelerated. The only explanation I can think of (besides ice cube just being wrong) was some charged particle got accelerated to absurd energies, then emitted a neutrino.