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Measurement of CP Violation at the $Υ(4S)$ without Time Ordering or $Δt$

A. Foland
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Abstract

I derive the expressions for the CP-violating asymmetry arising from interference between mixed and direct decays in the Upsilon(4S) system, for the case in which only one of the B decay times is observed, integrating over the decay time of the other B. I observe that neither the difference of the decay times Delta t, nor even their time-ordering, need be detected. A technique for measurement of the CP-violating weak decay parameter sin(2beta) is described which exploits this observation.

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A. Foland. 1999-07-08. Measurement of CP Violation at the $Υ(4S)$ without Time Ordering or $Δt$. https://doi.org/10.1103/physrevd.60.111301

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