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arXiv · 0707.1268

Direct CP violation of $B \to l ν$ in unparticle physics

Chao-Shang Huang·Xiao-Hong Wu
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Abstract

We have investigated the effects of unparticles in decays $B \to l ν$. It is found that the direct CP violation in the decays, which is zero in SM, can show up due to the CP conserving phase intrinsic in unparticle physics. For $l=τ$, the direct CP asymmetry can reach 30% for the scalar unparticle contribution, and 100% for the longitudinal vector unparticle contribution under the constraints of ${\rm Br}(B\toτν)$ and $νe$ elastic scattering. If both unparticle-lepton coupling universality and unparticle-quark coupling universality are assumed the constraint from $Br(π\to μν)$ leads that the direct CP violation in $B\to lν$ can only reach at most 8% and 1% for scalar and vector unparticle contributions respectively if $d_{\cal U} < 2$. If the direct CP violation is observed in the future it would give strong evidence for the existence of unparticle stuff.

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Chao-Shang Huang, Xiao-Hong Wu. 2008-03-24. Direct CP violation of $B \to l ν$ in unparticle physics. https://doi.org/10.1103/physrevd.77.075014

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