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A monte carlo study of the rare decay $B \to X_s \ell^+ \ell^-$

Kingman Cheung
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Abstract

We study, using a monte carlo approach, the rare decay $B\to X_s \ell^+ \ell^-$ including effects of the arbitrariness of the phase between the $ψ$ amplitudes and the perturbative amplitude, $b$-quark fermi motion inside the $B$ meson, and experimental smearing of lepton momenta. The fermi motion of $b$-quark inside the $B$ meson is modeled by the ACCMM model. We found that such effects reduce the sensitivities of the spectra of invariant mass and forward-backward asymmetry of the lepton pair to new physics; especially, in the neighborhood of the $ψ$ resonances. We also estimate the sensitivity range of Wilson coefficients with respect to the uncertainties.

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Kingman Cheung. 1998-09-24. A monte carlo study of the rare decay $B \to X_s \ell^+ \ell^-$. https://doi.org/10.1103/physrevd.59.097501

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