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تسجيل مستخدم جديدStudy of Lepton Universality at Belle
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تأليف
Markus Tobias Prim
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The Belle Collaboration presented three recent Belle analyses: The search for $Brightarrow l ugamma$ ($l = e, mu$) with improved hadronic tagging, the search for $Brightarrow mu u_mu$ with inclusive tagging and the test of lepton universality in $Brightarrow K^*ll$ ($l = e, mu$) decays.
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We present a measurement of $R_{K^{ast}}$, the branching fraction ratio ${{cal B}(Bto K^ast mu^+ mu^-)}$/ ${{cal B}(Bto K^ast e^+ e^-)}$, for both charged and neutral $B$ mesons. The ratio for the charged case, $R_{K{^{ast +}}}$, is the first measure
ment ever performed. In addition, we report absolute branching fractions for the individual modes in bins of the squared dilepton invariant mass, $q^2$. The analysis is based on a data sample of $711~mathrm{fb}^{-1}$, containing $772times 10^{6}$ $Bbar B$ events, recorded at the $Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. The obtained results are consistent with Standard Model expectations.
The coupling of the electroweak gauge bosons of the Standard Model (SM) to leptons is flavour universal. Extensions of the SM do not necessarily have this property. Rare decays of heavy flavour are suppressed in the SM and new particles may give size
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We search for lepton-number- and baryon-number-violating decays $tau^{-}tooverline{p}e^{+}e^{-}$, $pe^{-}e^{-}$, $overline{p}e^{+}mu^{-}$, $overline{p}e^{-}mu^{+}$, $overline{p}mu^{+}mu^{-}$, and $pmu^{-}mu^{-}$ using 921 fb$^{-1}$ of data, equivalen
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The search for multi-quark states beyond the constituent quark model (CQM) has resulted in the discovery of many new exotic states, starting with the observation of the X(3872), discovered by Belle in 2003. Also in the sector of charm-strange physics
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