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On the significance of new physics in $bto sell^+ell^-$ decays

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 نشر من قبل Nicola Serra
 تاريخ النشر 2021
  مجال البحث
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Motivated by deviations with respect to Standard Model predictions in $bto sell^+ell^-$ decays, we evaluate the global significance of the new physics hypothesis in this system, including the look-elsewhere effect for the first time. We estimate the trial-factor with psuedo-experiments and find that it can be as large as seven. We calculate the global significance for the new physics hypothesis by considering the most general description of a non-standard $bto sell^+ell^-$ amplitude of short-distance origin. Theoretical uncertainties are treated in a highly conservative way by absorbing the corresponding effects into a redefinition of the Standard Model amplitude. Using the most recent measurements of LHCb, ATLAS and CMS, we obtain the global significance to be $3.9$ standard deviations.



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