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Determination of $ΔΓ_s$ from Analysis of Untagged Decays $B^0_s\to J/ψϕ$ by Using the Method of Angular Moments

A. Bel'kov·S. Shulga
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Abstract

The performance of the method of angular moments on the $ΔΓ_s$ determination from analysis of untagged decays $B^0_s(t),\bar{B}^0_s(t)\to J/ψ(\to l^+l^-)ϕ(\to K^+K^-)$ is examined. The results of Monte Carlo studies with evaluation of measurement errors are presented. The method of angular moments gives stable results for the estimate of $ΔΓ_s$ and is found to be an efficient and flexible tool for the quantitative investigation of the $B^0_s\to J/ψϕ$ decay. The statistical error of the ratio $ΔΓ_s/Γ_s$ for values of this ratio in the interval [0.03, 0.3] was found to be independent on this value, being 0.015 for $10^5$ events.

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A. Bel'kov, S. Shulga. 2003-01-15. Determination of $ΔΓ_s$ from Analysis of Untagged Decays $B^0_s\to J/ψϕ$ by Using the Method of Angular Moments. https://arxiv.org/abs/hep-ph/0301105

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