pdgLive Home   >   STRANGE MESONS ($\mathit S$ = $\pm1$, $\mathit C$ = $\mathit B$ = 0)   >   ${{\mathit K}^{\pm}}$   >   A$_{FB}({{\mathit K}}{}^{\pm{}}_{{{\mathit \pi}} {{\mathit \mu}} {{\mathit \mu}} }$) = ${\Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})>0)}−\Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})<0)}\over \Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})>0)}+\Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})<0)}}$

FORWARD-BACKWARD ASYMMETRY IN ${{\mathit K}^{\pm}}$ DECAYS

A$_{FB}({{\mathit K}}{}^{\pm{}}_{{{\mathit \pi}} {{\mathit \mu}} {{\mathit \mu}} }$) = ${\Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})>0)}−\Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})<0)}\over \Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})>0)}+\Gamma\mathrm {(cos({{\mathit \theta}}_{{{\mathit K}} {{\mathit \mu}}})<0)}}$

INSPIRE   PDGID:

S010AFB

VALUE CL% DOCUMENT ID TECN  COMMENT $\bf{<0.009}$ 90 1 CORTINA-GIL 2022 A NA62 $2017 - 18$ data • • We do not use the following data for averages, fits, limits, etc. • • $<0.023$ 90 2 BATLEY 2011 A NA48 1  CORTINA-GIL 2022A measured the asymmetry A$_{FB}$ = ($0.0$ $\pm0.7$) $ \times 10^{-2}$. The quoted 90$\%$ C.L. was obtained via private communication and also presented at the Moriond 2023 conference. The authors will publish this limit in an addendum to the publication. 2  BATLEY 2011A gives a corresponding value of the asymmetry A$_{FB}$ = ($-2.4$ $\pm1.8$) $ \times 10^{-2}$.

References

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