Abstract: We discuss a nonrelativistic version of Georgi’s "unparticle physics". An "unparticle" is a field in a nonrelativistic conformal field theory characterized by a mass and a scaling dimension. It is realized approximately in high-energy nuclear reactions involving emission of a few neutrons with relative energies between about 0.1 MeV and 5 MeV. Conformal symmetry predicts a universal power law behavior of the inclusive cross section in this kinematic regime and relates it to the energy levels of spin-1/2 fermions in a harmonic trap. Certain bosonic systems may also show unparticle behavior. We argue that it may be possible to create unparticles of neutral D mesons in short-distance reactions at the LHC.

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