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$\mathit CP$ VIOLATION

$\mathit A_{CP}$ is defined as
${B( {{\overline{\mathit B}}} \rightarrow {{\overline{\mathit f}}} )–B( {{\mathit B}} \rightarrow {{\mathit f}} )\over B( {{\overline{\mathit B}}} \rightarrow {{\overline{\mathit f}}} )+B( {{\mathit B}} \rightarrow {{\mathit f}} )}$,
the $\mathit CP$-violation charge asymmetry of inclusive ${{\mathit B}^{\pm}}$ and ${{\mathit B}^{0}}$ decay.

$\mathit A_{CP}$( ${{\mathit B}}$ $\rightarrow$ ( s+d) ${{\mathit \gamma}}$ )

VALUE

DOCUMENT ID

TECN

COMMENT

$\bf{ 0.010 \pm0.031}$

OUR AVERAGE

$0.022$ $\pm0.039$ $\pm0.009$

BELL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$0.057$ $\pm0.060$ $\pm0.018$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$-0.10$ $\pm0.18$ $\pm0.05$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$-0.110$ $\pm0.115$ $\pm0.017$

BABR

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

$-0.079$ $\pm0.108$ $\pm0.022$

CLE2

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$

¹	Assumes equal production of ${{\mathit B}^{+}}$ and ${{\mathit B}^{0}}$ at the ${{\mathit \Upsilon}{(4S)}}$. Uses an opposite side lepton tag. Requires center-of-mass frame $\mathit E_{{{\mathit \gamma}}}$ $>$ 2.1 GeV.

²	Uses a fully reconstructed ${{\mathit B}}$ meson as a tag on the recoil side. Requires $\mathit E_{{{\mathit \gamma}}}$ $>$ 2.2 GeV.

³	Corresponds to $-0.27<\mathit A_{\mathit CP}<0.10$ at 90$\%$ CL.

Conservation Laws:

$\mathit CP$ INVARIANCE

References:

PRL 114 151601

Measurement of the Direct $\mathit CP$ Asymmetry in ${{\overline{\mathit B}}}$ $\rightarrow$ ${{\mathit X}_{{{s+d}}}}{{\mathit \gamma}}$ Decays with a Lepton Tag

PRL 109 191801

Precision Measurement of the ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{s}}}{{\mathit \gamma}}$ Photon Energy Spectrum, Branching Fraction, and Direct $\mathit CP$ Asymmetry $\mathit A_{CP}$( ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{{s+d}}}}{{\mathit \gamma}}$ )

PR D86 112008

Measurement of B( ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{s}}}{{\mathit \gamma}}$ ), the ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{s}}}{{\mathit \gamma}}$ Photon Energy Spectrum, and the Direct $\mathit CP$ Asymmetry in ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{{s+d}}}}{{\mathit \gamma}}$ Decays

PR D77 051103

Measurement of the ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{s}}}{{\mathit \gamma}}$ Branching Fraction and Photon Energy Spectrum using the Recoil Method

PRL 97 171803

Measurement of the Branching Fraction and Photon Energy Moments of ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{s}}}{{\mathit \gamma}}$ and $\mathit A_{CP}$( ${{\mathit B}}$ $\rightarrow$ ${{\mathit X}_{{s+d}}}{{\mathit \gamma}}$ )

PRL 86 5661

Bounds on the $\mathit CP$ Asymmetry in ${\mathit {\mathit b}}$ $\rightarrow$ ${\mathit {\mathit s}}$ ${{\mathit \gamma}}$ Decays

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