$\mathit CP$ VIOLATION PARAMETERS

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

INSPIRE   PDGID:
S042CPI
$\mathit C_{{{\mathit \pi}} {{\mathit \pi}}}$ is defined as (1$−\vert \lambda \vert ^2)/(1+\vert \lambda \vert ^2$), where the quantity $\lambda =\mathit q/{{\mathit p}}{{\overline{\mathit A}}_{{{f}}}}/{{\mathit A}_{{{f}}}}$ is a phase convention independent observable quantity for the final state ${{\mathit f}}$. For details, see the review on “$\mathit CP$ Violation” in the Reviews section.

VALUE DOCUMENT ID TECN  COMMENT
$\bf{ -0.314 \pm0.030}$ OUR AVERAGE
$-0.311$ $\pm0.045$ $\pm0.015$
AAIJ
2021O
 LHCB ${{\mathit p}}{{\mathit p}}$ at 13 TeV
$-0.34$ $\pm0.06$ $\pm0.01$
AAIJ
2018O
 LHCB ${{\mathit p}}{{\mathit p}}$ at 7, 8 TeV
$-0.33$ $\pm0.06$ $\pm0.03$ 1
DALSENO
2013
BELL ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$
$-0.25$ $\pm0.08$ $\pm0.02$
LEES
2013D
 BABR ${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit \Upsilon}{(4S)}}$
• • We do not use the following data for averages, fits, limits, etc. • •
$-0.38$ $\pm0.15$ $\pm0.02$
AAIJ
2013BO
 LHCB Repl. by AAIJ 2018O
$-0.21$ $\pm0.09$ $\pm0.02$
AUBERT
2007AF
 BABR Repl. by LEES 2013D
$-0.55$ $\pm0.08$ $\pm0.05$ 1
ISHINO
2007
BELL Repl. by DALSENO 2013
$-0.56$ $\pm0.12$ $\pm0.06$ 1
ABE
2005D
 BELL Repl. by ISHINO 2007
$-0.09$ $\pm0.15$ $\pm0.04$
AUBERT,BE
2005
BABR Repl. by AUBERT 2007AF
$-0.58$ $\pm0.15$ $\pm0.07$ 1
ABE
2004E
 BELL Repl. by ABE 2005D
$-0.77$ $\pm0.27$ $\pm0.08$ 1
ABE
2003G
 BELL Repl. by ABE 2004E.
$-0.94$ ${}^{+0.31}_{-0.25}$ $\pm0.09$ 1
ABE
2002M
 BELL Repl. by ABE 2003G
$-0.25$ ${}^{+0.45}_{-0.47}$ $\pm0.14$ 2
AUBERT
2002D
 BABR Repl. by AUBERT 2002Q
$-0.30$ $\pm0.25$ $\pm0.04$ 3
AUBERT
2002Q
 BABR Repl. by AUBERT,BE 2005
1  Paper reports $\mathit A_{{{\mathit \pi}} {{\mathit \pi}}}$ which equals to $−\mathit C_{{{\mathit \pi}} {{\mathit \pi}}}$.
2  Corresponds to 90$\%$ confidence range $-1.0<\mathit C_{{{\mathit \pi}} {{\mathit \pi}}}<0.47$.
3  Corresponds to 90$\%$ confidence range $-0.72<\mathit C_{{{\mathit \pi}} {{\mathit \pi}}}<0.12$.
Conservation Laws:
$\mathit CP$ VIOLATION OBSERVED
References