pdgLive

MEAN LIFE RATIO ${\mathit \tau}_{{{\mathit B}^{+}}}/{\mathit \tau}_{{{\mathit B}^{0}}}$

${\mathit \tau}_{{{\mathit B}^{+}}}/{\mathit \tau}_{{{\mathit B}^{0}}}$ (direct measurements)

INSPIRE JSON (beta) PDGID:

VALUE

EVTS

DOCUMENT ID

TECN

COMMENT

$\bf{ 1.076 \pm0.004}$

OUR EVALUATION $~~$(Produced by HFLAV)

$1.074$ $\pm0.005$ $\pm0.003$

LHCB

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

$1.088$ $\pm0.009$ $\pm0.004$

CDF

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.96 TeV

$1.080$ $\pm0.016$ $\pm0.014$

D0

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.96 TeV

$1.066$ $\pm0.008$ $\pm0.008$

BELL

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

$1.060$ $\pm0.021$ $\pm0.024$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.093$ $\pm0.066$ $\pm0.028$

CDF

${{\mathit p}}{{\overline{\mathit p}}}$ at 1.8 TeV

$1.082$ $\pm0.026$ $\pm0.012$

BABR

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

$1.085$ $\pm0.059$ $\pm0.018$

ALEP

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.079$ $\pm0.064$ $\pm0.041$

OPAL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.110$ $\pm0.056$ ${}^{+0.033}_{-0.030}$

CDF

${{\mathit p}}{{\overline{\mathit p}}}$ at $1.8$ TeV

$1.09$ $\pm0.07$ $\pm0.03$

L3

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.01$ $\pm0.07$ $\pm0.06$

SLD

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.27$ ${}^{+0.23}_{-0.19}$ ${}^{+0.03}_{-0.02}$

ALEP

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.00$ ${}^{+0.17}_{-0.15}$ $\pm0.10$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$1.06$ ${}^{+0.13}_{-0.11}$ $\pm0.10$

DLPH

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$0.99$ $\pm0.14$ ${}^{+0.05}_{-0.04}$

OPAL

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

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

$1.091$ $\pm0.023$ $\pm0.014$

BELL

Repl. by ABE 2005B

$1.06$ $\pm0.07$ $\pm0.02$

CDF

Repl. by ACOSTA 2002C

$1.01$ $\pm0.11$ $\pm0.02$

CDF

Repl. by ABE 1998Q

$1.03$ $\pm0.08$ $\pm0.02$

ALEP

${{\mathit e}^{+}}$ ${{\mathit e}^{-}}$ $\rightarrow$ ${{\mathit Z}}$

$0.98$ $\pm0.08$ $\pm0.03$

ALEP

Repl. by BARATE 2000R

$1.02$ $\pm0.16$ $\pm0.05$

269

CDF

Repl. by ABE 1998B

$1.11$ ${}^{+0.51}_{-0.39}$ $\pm0.11$

188

DLPH

Sup. by ABREU 1995Q

$1.01$ ${}^{+0.29}_{-0.22}$ $\pm0.12$

253

DLPH

Sup. by ADAM 1995

$1.0$ ${}^{+0.33}_{-0.25}$ $\pm0.08$

130

OPAL

Sup. by AKERS 1995T

$0.96$ ${}^{+0.19}_{-0.15}$ ${}^{+0.18}_{-0.12}$

154

ALEP

Sup. by BUSKULIC 1996J

¹	Measured using ${{\mathit B}}$ $\rightarrow$ ${{\mathit J / \psi}}{{\mathit K}^{(*)}}$ decays.

²	Measured mean life using fully reconstructed decays (${{\mathit J / \psi}}{{\mathit K}^{(*)}}$).

³	Data analyzed using ${{\mathit D}}$ /${{\mathit D}^{*}}{{\mathit \mu}}$ X vertices.

⁴	Measurement performed using a combined fit of $\mathit CP$-violation, mixing and lifetimes.

⁵	Measurement performed using an inclusive reconstruction and ${{\mathit B}}$ flavor identification technique.

⁶	Measured using fully reconstructed decays.

⁷	Events are selected in which one ${{\mathit B}}$ meson is fully reconstructed while the second ${{\mathit B}}~$meson is reconstructed inclusively.

⁸	Data analyzed using charge of secondary vertex.

⁹	ABREU 1995Q assumes B(${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}^{**-}}{{\mathit \ell}^{+}}{{\mathit \nu}_{{{{{\mathit \ell}}}}}}$) = $3.2$ $\pm1.7\%$.

¹⁰	Data analyzed using vertex-charge technique to tag ${{\mathit B}}$ charge.

¹¹	AKERS 1995T assumes B(${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit D}_{{{s}}}}{}^{(\ast{})}$ ${{\mathit D}^{0}}{}^{(\ast{})}$) = $5.0$ $\pm0.9\%$ to find ${{\mathit B}^{+}}/{{\mathit B}^{0}}$ yield.

¹²	Combined result of ${{\mathit D}}/{{\mathit D}^{*}}{{\mathit \ell}}$ X analysis and fully reconstructed ${{\mathit B}}$ analysis.

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