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bhadron species  average lifetime  average lifetime relative to B^{0} average lifetime 
B^{0}  1.519 ± 0.007 ps  
B^{+}  1.642 ± 0.008 ps  1.079 ± 0.007 
B_{s}  1.509 ± 0.012 ps  0.993 ± 0.009 
B_{c}  0.458 ± 0.030 ps  
Λ_{b}  1.413 ± 0.030 ps  0.930 ± 0.020 
Ξ_{b}^{−}  1.56 +0.27 −0.25 ps  
Ω_{b}^{−}  1.13 +0.53 −0.40 ps  
Ξ_{b}^{−}, Ξ_{b}^{0} mixture  1.49 +0.19 −0.18 ps  
bbaryon mixture  1.378 ± 0.027 ps  0.907 ± 0.018 
bhadron mixture  1.566 ± 0.009 ps 
The table below gives other B_{s} lifetime averages, consisting of different mixtures of the two B_{s} mass eigenstates. The "B_{s} → flavour specific" lifetime is measured mainly with B_{s} → D_{s} lepton X decays; it is used as input to extract the long and short lifetimes of the B_{s} system (see next section). The "B_{s} → D_{s} X" lifetime is illdefined because it includes an unknown proportion of short and long components. The "B_{s} → J/ψ φ" lifetime is an average of the results from single exponential fits. Nowadays, the time dependence and the angular dependence of the B_{s} → J/ψ φ decays is analysed in a more sophisticated way in order to extract separately the long and short lifetimes (see further below).
mixture of the two B_{s} mass eigenstates 
average lifetime from single exponential fits 
B_{s} → flavour specific  1.463 ± 0.032 ps 
B_{s} → D_{s} X  1.466 ± 0.031 ps 
B_{s} → J/ψ φ  1.430 ± 0.050 ps 
Combined result on the relative decay width difference in the B^{0} system:
s×ΔΓ_{d}/Γ_{d} = 0.015 ± 0.018  from Belle, BABAR and DELPHI 
The quantity s = sign(Re(λ_{CP})), where λ_{CP} = (q/p)×A_{CP}/A_{CP} refers to a CPeven final state (e.g. J/ψK_{L}), is predicted to be equal to s= +1 to a high degree of confidence from the Standard Model fits to all available constraints on the unitarity triangle.
The CDF, D0 and LHCb analyses of the B_{s} → J/ψ φ decay provide information on 1/Γ_{s}, ΔΓ_{s} and the weak phase φ_{s}^{ccs}, defined as the phase difference between the mixing amplitude and the b→ccs decay amplitude of the B_{s} meson. A combined value of the average decay width 1/Γ_{s} is obtained as a weighted average of the quoted results, assuming no correlations. Using the likelihood scans from the different analyses, a combined value of ΔΓ_{s} is obtained from a 2D fit of ΔΓ_{s} and φ_{s}^{ccs}. These two averages are then used as input to a fit where the following additional constraints are applied, using effective lifetime measurements:
Fit results from CDF, D0 and LHCb data 
without constraint from effective lifetime measurements 
with constraints I and II 
with constraints I, II and III 
1/Γ_{s}  1.514 ± 0.013 ps  1.520 ± 0.013 ps  1.509 ± 0.012 ps 
τ_{Short} = 1/Γ_{L}  1.403 ± 0.019 ps  1.412 ± 0.017 ps  1.408 ± 0.017 ps 
τ_{Long} = 1/Γ_{H}  1.645 ± 0.027 ps  1.644 ± 0.025 ps  1.626 ± 0.023 ps 
ΔΓ_{s}  +0.105 ± 0.015 ps^{−1}  +0.100 ± 0.014 ps^{−1}  +0.095 ± 0.014 ps^{−1} 
ΔΓ_{s}/Γ_{s}  +0.159 ± 0.023  +0.152 ± 0.021  +0.144 ± 0.021 
Above plots: (1/Γ_{s}, ΔΓ_{s}) gif /
(1/Γ_{s}, ΔΓ_{s}) eps /
(1/Γ_{s}, ΔΓ_{s}) pdf /
Δm_{d} = 0.507 ± 0.004 ps^{−1}  from timedependent measurements at ALEPH, DELPHI, L3, OPAL, CDF, D0, BABAR, BELLE, LHCb 
χ_{d} = 0.182 ± 0.015  from timeintegrated measurements at ARGUS and CLEO 
Assuming no CP violation in the mixing and no width difference in the B^{0} system, and using the B^{0} lifetime average of 1.519 ± 0.007 ps, all above measurements can be combined to yield the following world averages:
Δm_{d} =
0.507
±
0.004
ps^{−1}
x_{d} = 0.770 ± 0.008 χ_{d} = 0.1862 ± 0.0023 
from all ALEPH, DELPHI, L3, OPAL, CDF, D0, BABAR, BELLE, LHCb, ARGUS and CLEO measurements 
In the plot below, all individual measurements are listed as quoted by the experiments; they might assume different physics inputs. The averages (which take into account all known correlations) are quoted after adjusting the individual measurements to the common set of physics inputs. The χ_{d} average from ARGUS and CLEO is converted to a Δm_{d} measurement assuming no CP violation, no width difference in the B^{0} system and a B^{0} lifetime of 1.519 ± 0.007 ps.
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Same without average including timeintegrated (χ_{d}) measurements:
colour eps /
blackandwhite eps /
Only measurements and average at LEP and CDF1:
colour eps /
blackandwhite eps /
Only measurements and average at LEP:
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blackandwhite eps /
Only measurements and average at asymmetric B factories:
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In the plot below,
the individual experiment averages are listed as quoted by the experiments
(or computed by the working group without performing any adjustments);
they might assume different physics inputs. The global averages are quoted
after adjusting the individual measurements to the common set of physics
inputs. The χ_{d} average from ARGUS and CLEO is converted to a Δm_{d} measurement
assuming no CP violation, no width difference in the B^{0} system and a
B^{0} lifetime of
1.519
±
0.007
ps.
colour gif /
colour eps /
blackandwhite eps /
colour gif /
colour eps /
Δm_{s} = 17.719 ± 0.043 ps^{−1}  CDF, LHCb 
With a mean B^{0}_{s} lifetime of 1/Γ_{s} = 1.509 ± 0.012 ps, a decay width difference of ΔΓ_{s} = +0.095 ± 0.014 ps^{−1} and the assumption of no CP violation in B^{0}_{s} mixing, this leads to
x_{s} = 26.74 ± 0.22 
χ_{s} = 0.499305 ± 0.000011 
The parameters q/p, A_{SL} and Re(ε_{B})/(1+ε_{B}^{2}) are thus equivalent. There is CP violation in the mixing if q/p is different from 1, i.e. A_{SL} is different from 0.
Averages are given below separately for the B^{0} and the B_{s} systems. Two sets of averages are given for the B^{0} system in the first table: a first set using only measurements performed at Υ(4S) machines, and a second set using all measurements (excluding those that assume no CP violation in B_{s} mixing). The second table presents an average for the B_{s} system. Measurements performed at high energy that do not separate the B^{0} and B_{s} contributions are no longer used to obtain the final averages (at this time, the only measurements at high energy used in the averages are from D0).
CP violation parameter in B^{0} mixing  
q/p =
1.0002
±
0.0028
A_{SL} = −0.0005 ± 0.0056 Re(ε_{B})/(1+ε_{B}^{2}) = −0.0001 ± 0.0014 
from measurements at the Υ(4S) 
q/p =
1.0017
±
0.0017
A_{SL} −0.0033 ± 0.0033 Re(ε_{B})/(1+ε_{B}^{2}) = −0.0008 ± 0.0008 
world average 
CP violation parameter in B_{s} mixing  
q/p =
1.0052
±
0.0032
A_{SL} = −0.0105 ± 0.0064 
world average 
The above world averages A_{SL}(B^{0}) = −0.0033 ± 0.0033 and A_{SL}(B_{s}) = −0.0105 ± 0.0064 are obtained from a twodimensional fit of the CLEO, BABAR, Belle and D0 results: the correlation coefficient between them is found to be −0.574 . This is illustrated in the plot below, where the vertical blue band is the B factory average of A_{SL}(B^{0}), the horizontal green band is the D0 measurement of A_{SL}(B_{s}) with semileptonic B_{s} decays, the green ellipse is the D0 measurement with samesign dileptons, and the read ellipse is the result of the twodimensional averaging. The red point close to (0,0) is the Standard Model prediction [A. Lenz and U. Nierste, arXiv:1102.4274 [hepph]] with errors bars multiplied by 10.
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colour pdf /
2D fit results from CDF, D0 and LHCb data 

φ_{s}^{ccs}  −0.044 +0.090 −0.085 
ΔΓ_{s}  +0.105 ± 0.015 ps^{−1} 
The two plots below show different 68% confidencelevel contours in the (φ_{s}^{ccs}, ΔΓ_{s}) plane. The left plot shows the individual contours of CDF, D0 and LHCb, their combined contour (solid line and shaded area), as well as the Standard Model predictions. The prediction for φ_{s}^{ccs} is taken as the indirect determination of −2β_{s} via a global fit to experimental data within the Standard Model, −2β_{s} = −0.0363^{+0.0016}_{−0.0015} [CKMfitter, Phys. Rev. D84, 033005 (2011)] , while the Standard Model prediction for ΔΓ_{s} is 0.087 ±0.021 ps^{−1} [A. Lenz and U. Nierste, arXiv:1102.4274 [hepph]]. The combined result is consistent with these predictions at the 0.8 σ level. The right plot shows the same combined contour and SM predictions together with the regions allowed at 68% and 95% CL by the average measurements A_{SL}(B_{s}) = −0.0105 ± 0.0064 and Δm_{s} = 17.719 ± 0.043 ps^{−1}, through the relation tanφ_{12} = A_{SL}(B_{s}) × Δm_{s} / ΔΓ_{s}, where φ_{12} = arg(−M_{12}/Γ_{12}) is the phase mismatch between the offdiagonal elements of the mass and decay matrices of the B_{s}−B_{s} system. This region is drawn under the assumption that possible new physics will not affect the phase difference φ_{s}^{ccs}−φ_{12}, i.e. that this phase difference is equal to its Standard Model prediction [A. Lenz and U. Nierste, arXiv:1102.4274 [hepph]].
CDF, D0, LHCb, and their average: colour gif /
colour eps /
colour pdf /
average and region allowed by A_{SL}(B_{s}): colour gif /
colour eps /
colour pdf /
f^{+−}/f^{00} = 1.056 ± 0.028  from ratios of reconstructed B^{+} and B^{0} mesons
at BABAR, BELLE and CLEO
(assumptions made, see text above) 
f^{00} = 0.487 ± 0.013  from absolute measurement of
B^{0} mesons at BABAR
(no assumptions) 
Assuming f^{+−} + f^{00} = 1, the above two independent results
(which are consistent with each other)
can be combined to yield:
bhadron species  fraction in Υ(4S) decay  ratio 
B^{+} B^{−}  f^{+−} = 0.513 ± 0.006  f^{+−}/f^{00} = 1.055 ± 0.025 
B^{0} B^{0}  f^{00} = 0.487 ± 0.006 
final states  fraction in Υ(5S) decays  ratio of fractions 
B_{u,d}^{(*)} B_{u,d}^{(*)}(π(π))  f_{u,d} = 0.759 +0.027 −0.040  
B_{s}^{(*)} B_{s}^{(*)}  f_{s} = 0.199 ± 0.030  f_{s} / f_{u,d} = 0.262 +0.051 −0.043 
no open bottomness  f_{noB} = 0.042 +0.046 −0.006 
The plot below shows the published measurements of f_{s}.
All values have been obtained assuming f_{noB}=0.
They are quoted as in the original publication,
except for the most recent measurement of Belle which
is quoted as f_{s} = 1−f_{ud}. The average value of
all these measurements is quoted with or without the assumption that
f_{noB}=0,
after performing adjustments
to common external inputs.
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bhadron species  fraction in Z decays  correlation with f(B_{s})  correlation with f(bbaryon) 
B_{s}  f(B_{s}) = 0.103 ± 0.009  
b baryons  f(bbaryon) = 0.090 ± 0.015  +0.036  
B^{0} or B^{+}  f(B_{d}) = f(B_{u}) = 0.403 ± 0.009  −0.521  −0.871 
B_{s} / (B^{0} or B^{+}) ratio  f(B_{s})/f(B_{d}) = 0.256 ± 0.025 
χ(LEP) = 0.1259 ± 0.0042  LEP average from LEP EW WG 
bhadron species  fraction in pp collisions at 1.8−2 TeV 
correlation with f(B_{s})  correlation with f(bbaryon) 
B_{s}  f(B_{s}) = 0.103 ± 0.012  
b baryons  f(bbaryon) = 0.236 ± 0.067  −0.530  
B^{0} or B^{+}  f(B_{d}) = f(B_{u}) = 0.330 ± 0.030  +0.379  −0.986 
B_{s} / (B^{0} or B^{+}) ratio  f(B_{s})/f(B_{d}) = 0.311 ± 0.037 
χ(Tevatron) = 0.127 ± 0.008  Average of CDF and D0 measurements 
bhadron species  fraction at high energy  correlation with f(B_{s})  correlation with f(bbaryon) 
B_{s}  f(B_{s}) = 0.107 ± 0.005  
b baryons  f(bbaryon) = 0.091 ± 0.015  −0.136  
B^{0} or B^{+}  f(B_{d}) = f(B_{u}) = 0.401 ± 0.007  −0.224  −0.935 
B_{s} / (B^{0} or B^{+}) ratio  f(B_{s})/f(B_{d}) = 0.266 ± 0.015 
χ = 0.1259 ± 0.0042  LEP average from LEP EW WG 
χ = 0.127 ± 0.008  Tevatron average 
χ = 0.1260 ± 0.0037  Weighted average of above two 
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