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Hadron Spectra and Spectral Moments in the Decay B \to X_s \ell^+ \ell^- using HQET

A. Ali·G. Hiller
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Abstract

We compute the leading order (in alpha_s) perturbative QCD and power (1/m_b^2) corrections to the hadronic invariant mass and hadron energy spectra in the decay B \to X_s \ell^+ \ell^- in standard model using the heavy quark expansion technique (HQET). Results for the first two hadronic moments < S_H^n> and , n=1,2, are presented here working out their sensitivity on the HQET parameters lambda_1 and \barΛ. Data from the forthcoming B facilities can be used to measure the short-distance contribution in B \to X_s \ell^+ \ell^- and determine the HQET parameters from the moments . This can be combined with the analysis of semileptonic decays B \to X \ell ν_\ell to determine them precisely.

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A. Ali, G. Hiller. 1998-03-20. Hadron Spectra and Spectral Moments in the Decay B \to X_s \ell^+ \ell^- using HQET. https://doi.org/10.1103/physrevd.58.071501

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