Journal of High Energy Physics

, 2017:176 | Cite as

Direct determination of Wilson coefficients using B 0K ∗0 μ + μ decays

  • T. Hurth
  • C. Langenbruch
  • F. Mahmoudi
Open Access
Regular Article - Experimental Physics


A method to directly determine the Wilson coefficients for rare bs transitions using B 0K ∗0 μ + μ decays in an unbinned maximum likelihood fit is presented. The method has several advantages compared to the conventional determination of the Wilson coefficients from angular observables that are determined in bins of q 2, the square of the mass of the dimuon system. The method uses all experimental information in a more efficient way and automatically accounts for experimental correlations. Performing pseudoexperiments, we show the improved sensitivity of the proposed method for the Wilson coefficients. We also demonstrate that it will be possible to use the method with the combined Run 1 and 2 data sample taken by the LHCb experiment.


B physics Flavour Changing Neutral Currents Hadron-Hadron scattering (experiments) Rare decay 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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© The Author(s) 2017

Authors and Affiliations

  1. 1.PRISMA Cluster of Excellence and Institute for Physics (THEP)Johannes Gutenberg UniversityMainzGermany
  2. 2.I. Physikalisches Institut BAachenGermany
  3. 3.Univ Lyon, Univ Lyon 1, CNRS/IN2P3, Institut de Physique Nucléaire de Lyon UMR5822VilleurbanneFrance
  4. 4.CERN, Theoretical Physics DepartmentGeneva 23Switzerland
  5. 5.Institut Universitaire de FranceParisFrance

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