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$\mathit CP$ VIOLATION PARAMETERS

$\mathit S_{{{\mathit \pi}} {{\mathit \pi}}}$ (${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$)

INSPIRE JSON (beta) PDGID:

$\mathit S_{{{\mathit \pi}} {{\mathit \pi}}}$ = 2Im$\lambda /(1+\vert \lambda \vert ^2$), see the note in the $\mathit C_{{{\mathit \pi}} {{\mathit \pi}}}$ datablock above.

VALUE

DOCUMENT ID

TECN

COMMENT

$\bf{ -0.670 \pm0.030}$

OUR AVERAGE

$-0.706$ $\pm0.042$ $\pm0.013$

LHCB

${{\mathit p}}{{\mathit p}}$ at 13 TeV

$-0.63$ $\pm0.05$ $\pm0.01$

LHCB

${{\mathit p}}{{\mathit p}}$ at 7, 8 TeV

$-0.64$ $\pm0.08$ $\pm0.03$

BELL

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

$-0.68$ $\pm0.10$ $\pm0.03$

BABR

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

• • We do not use the following data for averages, fits, limits, etc. • •

$-0.71$ $\pm0.13$ $\pm0.02$

LHCB

Repl. by AAIJ 2018O

$-0.60$ $\pm0.11$ $\pm0.03$

BABR

Repl. by LEES 2013D

$-0.61$ $\pm0.10$ $\pm0.04$

BELL

Repl. by DALSENO 2013

$-0.67$ $\pm0.16$ $\pm0.06$

BELL

Repl. by ISHINO 2007

$-0.30$ $\pm0.17$ $\pm0.03$

BABR

Repl. by AUBERT 2007AF

$-1.00$ $\pm0.21$ $\pm0.07$

BELL

Repl. by ABE 2005D

$-1.23$ $\pm0.41$ ${}^{+0.08}_{-0.07}$

BELL

Repl. by ABE 2004E.

$-1.21$ ${}^{+0.38}_{-0.27}$ ${}^{+0.16}_{-0.13}$

BELL

Repl. by ABE 2003G

$0.03$ ${}^{+0.52}_{-0.56}$ $\pm0.11$

BABR

Repl. by AUBERT 2002Q

$0.02$ $\pm0.34$ $\pm0.05$

BABR

Repl. by AUBERT,BE 2005

¹	An isospin analysis using other BELLE measurements, disfavors the region of 23.8$^\circ{}<$ ${{\mathit \phi}_{{{2}}}}<$ 66.8$^\circ{}$ at 68$\%$ CL.

²	Rule out the $\mathit CP$-conserving case, $\mathit C_{{{\mathit \pi}} {{\mathit \pi}} }$ = $\mathit S_{{{\mathit \pi}} {{\mathit \pi}} }$ = 0, at the 5.4 sigma level.

³	Rule out the $\mathit CP$-conserving case, $\mathit C_{{{\mathit \pi}} {{\mathit \pi}} }$ = $\mathit S_{{{\mathit \pi}} {{\mathit \pi}} }$ = 0, at the 5.2 sigma level.

⁴	Corresponds to 90$\%$ confidence range $-0.89<\mathit S_{{{\mathit \pi}} {{\mathit \pi}}}<0.85$.

⁵	Corresponds to 90$\%$ confidence range $-0.54<\mathit S_{{{\mathit \pi}} {{\mathit \pi}}}<0.58$.

Conservation Laws:

$\mathit CP$ VIOLATION OBSERVED

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