Unparticles at heavy flavor scales:CPviolating phenomena

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Coupling the scale invariant unparticle sector to flavor physics and assuming that it remains scale invariant I investigate its consequences in heavy flavor physics. A characteristic feature of unparticle physics is a $CP$-even phase leading to novel $CP$ violating phenomena. The phase is large, based on the assumption that the unparticle sector is strongly self-coupled. I consider the $CP$ asymmetry in the leptonic decay ${B}^{+}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}\ensuremath{\nu}$ and the hadronic decay ${B}_{d}\ensuremath{\rightarrow}{D}^{+}{D}^{\ensuremath{-}}$, taking into account constraints of branching ratios and time dependent $CP$ asymmetries. It turns out that the $CP$ asymmetry can be very large even for small couplings because the unparticle interaction term has a lower scaling dimension than the four-Fermi weak interaction term. $CP$ asymmetries in leptonic decays such as ${B}^{+}\ensuremath{\rightarrow}{\ensuremath{\tau}}^{+}\ensuremath{\nu}$ are neither experimentally searched for nor predicted by any other model. I show that the novel $CP$ violation is consistent with the $CPT$ theorem. I identify the $CP$ compensating mode in the unparticle sector and explicitly demonstrate the exact cancellation as demanded by the $CPT$ theorem.