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arXiv · 1404.2531

On new physics in $\Delta \Gamma_d$

Christoph Bobeth·Ulrich Haisch·Alexander Lenz·Ben Pecjak·Gilberto Tetlalmatzi-Xolocotzi
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Abstract

Motivated by the recent measurement of the dimuon asymmetry by the D{\O} collaboration, which could be interpreted as an enhanced decay rate difference in the neutral $B_d$-meson system, we investigate the possible size of new-physics contributions to $\Delta \Gamma_d$. In particular, we perform model-independent studies of non-standard effects associated to the dimension-six current-current operators $(\bar{d} p)(\bar p^{\hspace{0.25mm}\prime} b)$ with $p,p^\prime= u,c$ as well as $(\bar{d}b) (\bar\tau\tau)$. In both cases we find that for certain flavour or Lorentz structures of the operators sizable deviations of $\Delta \Gamma_d$ away from the Standard Model expectation cannot be excluded in a model-independent fashion.

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Christoph Bobeth, Ulrich Haisch, Alexander Lenz, Ben Pecjak, Gilberto Tetlalmatzi-Xolocotzi. 2014-04-09. On new physics in $\Delta \Gamma_d$. https://doi.org/10.1007/jhep06(2014)040

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