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The generic unparticle propagator may be modified in two ways. Breaking the conformal symmetry effectively adds a mass term to the propagator, while considering vacuum polarization corrections adds a width-like term. Both of these modifications resul t naturally from the coupling of the unparticle to standard model (SM) fields. We explore how these modifications to the propagator affect the calculation of the lepton anomalous magnetic moment using an integral approximation of the propagator that is accurate for $dlesssim1.5$, where $d$ is the unparticle dimension. We find that for this range of $d$ and various values of the conformal breaking scale $mu$, the value of $g-2$ calculated when allowing various SM fermions to run in the unparticle self-energy loops does not significantly deviate from the value of $g-2$ when the width term is ignored. We also investigate the limits on a characteristic mass scale for the unparticle sector as a function of $mu$ and $d$.
We examine W pair production in the Noncommutative Standard Model constructed with the Seiberg-Witten map. Consideration of partial wave unitarity in the reactions WW to WW and e+e- to WW shows that the latter process is more sensitive and that tree- level unitarity is violated when scattering energies are of order a TeV and the noncommutative scale is below about a TeV. We find that WW production at the LHC is not sensitive to scales above the unitarity bounds. WW production in e+e- annihilation, however, provides a good probe of such effects with noncommutative scales below 300-400 GeV being excluded at LEP-II, and the ILC being sensitive to scales up to 10-20 TeV. In addition, we find that the ability to measure the helicity states of the final state W bosons at the ILC provides a diagnostic tool to determine and disentangle the different possible noncommutative contributions.
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