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bhadron species  average lifetime  average lifetime relative to B^{0} average lifetime 
B^{0}  1.520 ± 0.004 ps  
B^{+}  1.638 ± 0.004 ps  1.076 ± 0.004 
B_{s}^{0}  1.505 ± 0.004 ps  0.990 ± 0.004 
B_{s}_{L}  1.417 ± 0.006 ps  
B_{s}_{H}  1.605 ± 0.010 ps  
B_{c}^{+}  0.507 ± 0.009 ps  
Λ_{b}  1.466 ± 0.010 ps  0.965 ± 0.007 
Ξ_{b}^{−}  1.560 ± 0.040 ps  
Ξ_{b}^{0}  1.464 ± 0.031 ps  
Ω_{b}^{−}  1.63 +0.18 −0.17 ps  
bhadron average (weighted by fractions in Z decays) 
1.566 ± 0.003 ps 
The tables below give a number of effective B_{s} lifetime averages, measured from single exponential fits of the proper time distributions of B_{s} decays to a number of interesting final states. In general each final state may be a different mixture of the two B_{s} mass eigenstates, and hence the effective lifetime falls somewhere between 1/Γ_{L} and 1/Γ_{H}. 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} → 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 
effective lifetime from single exponential fits 
B_{s} → flavour specific  1.511 ± 0.014 ps 
B_{s} → J/ψ φ  1.478 ± 0.012 ps 
The two tables below report effective B_{s} lifetime averages for final states that are either pure CPeven or pure CPodd eigenstates. If the corresponding B_{s} decays are dominated by a single weak phase and if CP violation can be neglected, then the effective lifetime for decays to CPeven (CPodd) eigenstates corresponds to 1/Γ_{L} (1/Γ_{H}). These averages are used as constraints in the fit to determine Γ_{s} and ΔΓ_{s} (see further below).
CPeven final state  effective lifetime from single exponential fits 
B_{s} → D^{+}_{s}D^{−}_{s}  1.379 ± 0.031 ps 
CPodd final state  effective lifetime from single exponential fits 
B_{s} → J/ψ f_{0}, J/ψ ππ  1.658 ± 0.032 ps 
Combined result on the relative decay width difference in the B^{0} system:
s×ΔΓ_{d}/Γ_{d} = −0.002 ± 0.010  from DELPHI, BABAR, Belle, ATLAS and LHCb 
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 ATLAS, CMS, CDF and D0 analyses of the B_{s} → J/ψ φ decay, as well as the LHCb analyses of the B_{s} → J/ψKK and B_{s} → J/ψππ decays provide information on 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. Combined values of the average decay width Γ_{s} and the decay width difference ΔΓ_{s} are obtained from of a twodimensional fit of the experimental results. In this fit, the CPviolating phase φ_{s}^{ccs} is fixed to zero, which is consistent with the φ_{s}^{ccs}average described below. In addition an untagged B_{s} → J/ψ φ analysis by CMS providing a measurement of ΔΓ_{s} (and assuming φ_{s}^{ccs} = 0) is used in the above mentioned fit. The correlation between Γ_{s} and ΔΓ_{s} in each analysis is taken into account (but correlations with other parameters are ignored). The following additional constraints are applied, using effective lifetime measurements:
Fit results from ATLAS, CDF, CMS, D0 and LHCb data 
without constraint from effective lifetime measurements 
with constraints I and II 
with constraints I, II and III 
Γ_{s}  0.6647 ± 0.0022 ps^{−1}  0.6640 ± 0.0021 ps^{−1}  0.6643 ± 0.0020 ps^{−1} 
1/Γ_{s}  1.504 ± 0.005 ps  1.506 ± 0.005 ps  1.505 ± 0.004 ps 
τ_{Short} = 1/Γ_{L}  1.420 ± 0.006 ps  1.417 ± 0.006 ps  1.417 ± 0.006 ps 
τ_{Long} = 1/Γ_{H}  1.599 ± 0.011 ps  1.607 ± 0.011 ps  1.605 ± 0.010 ps 
ΔΓ_{s}  +0.079 ± 0.006 ps^{−1}  +0.083 ± 0.006 ps^{−1}  +0.083 ± 0.006 ps^{−1} 
ΔΓ_{s}/Γ_{s}  +0.119 ± 0.010  +0.125 ± 0.009  +0.124 ± 0.009 
correlation ρ(Γ_{s}, ΔΓ_{s})  −0.324  −0.293  −0.239 
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Right plot in several formats:
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Δm_{d} = 0.5065 ± 0.0019 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 1.520 ± 0.004 ps (the experimental average listed above), all above measurements can be combined to yield the following world averages:
Δm_{d} =
0.5064
±
0.0019
ps^{−1}
x_{d} = 0.770 ± 0.004 χ_{d} = 0.1860 ± 0.0011 
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 1.520 ± 0.004 ps.
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Same without average including timeintegrated (χ_{d}) measurements:
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Only measurements and average at LEP and CDF1:
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Only measurements and average at LEP:
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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
1.520
±
0.004
ps.
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Δm_{s} = 17.757 ± 0.021 ps^{−1}  CDF, LHCb 
With a mean B^{0}_{s} lifetime of 1/Γ_{s} = 1.505 ± 0.004 ps, a decay width difference of ΔΓ_{s} = +0.083 ± 0.006 ps^{−1} and the assumption of no CP violation in B^{0}_{s} mixing, this leads to
x_{s} = 26.73 ± 0.09 
χ_{s} = 0.499304 ± 0.000005 
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 and LHCb).
CP violation parameter in B^{0} mixing  
q/p =
1.0009
±
0.0013
A_{SL} = −0.0019 ± 0.0027 Re(ε_{B})/(1+ε_{B}^{2}) = −0.0005 ± 0.0007 
from measurements at the Υ(4S) 
q/p =
1.0007
±
0.0009
A_{SL} = −0.0015 ± 0.0017 Re(ε_{B})/(1+ε_{B}^{2}) = −0.0004 ± 0.0004 
world average 
CP violation parameter in B_{s} mixing  
q/p =
1.0038
±
0.0021
A_{SL} = −0.0075 ± 0.0041 
world average 
The above world averages A_{SL}(B^{0}) = −0.0015 ± 0.0017 and A_{SL}(B_{s}) = −0.0075 ± 0.0041 are obtained from a twodimensional fit of the CLEO, BABAR, Belle, D0 and LHCb results: the correlation coefficient between them is found to be −0.158 . This is illustrated in the plot below, where the vertical band is the average of the pure B^{0} measurements performed at CLEO, BABAR, Belle, D0 and LHCb, the horizontal band is the average of the pure B_{s} measurements performed at D0 and LHCb 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 [M. Artuso, G. Borissov and A. Lenz, arXiv:1511.09466 [hepph]] with errors bars multiplied by 10. The prediction and experimental average deviate from each other by 1.5 σ.
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CP violation in B_{s} mixing is caused by the weak phase difference
φ_{12}=arg[−M_{12}/Γ_{12}],
where M_{12} and Γ_{12}
are the offdiagonal elements of the mass and decay matrices. The tangent of this phase difference
can be estimated (approximately) as A_{SL}(B_{s}) Δm_{s}/ΔΓ_{s}=
−1.6
±
0.9
using the above averages of A_{SL}(B_{s}), Δm_{s} and
ΔΓ_{s}.
Combined result from CDF, D0, ATLAS, CMS and LHCb data (complete list of inputs and references) 

φ_{s}^{ccs}  −0.033 ± 0.033 
The plot below shows, in the (φ_{s}^{ccs}, ΔΓ_{s}) plane, the individual 68% confidencelevel contours of ATLAS, CMS, CDF, D0 and LHCb, their combined contour (solid line and shaded area), as well as the Standard Model predictions (thin black rectangle). 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} = −0.0376 ^{ +0.0008 }_{ −0.0007 } [CKMfitter, Phys. Rev. D84, 033005 (2011), updated with Summer 2015 results], while the Standard Model prediction for ΔΓ_{s} is 0.088 ±0.020 ps^{−1} [M. Artuso, G. Borissov and A. Lenz, arXiv:1511.09466 [hepph], Eq. 89]. The combined result is consistent with these predictions.
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f^{+−}/f^{00} = 1.059 ± 0.027  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^{+−} = 0.514 ± 0.006  f^{+−}/f^{00} = 1.058 ± 0.024 
B^{0} B^{0}  f^{00} = 0.486 ± 0.006 
final states  fraction in Υ(5S) decays  ratio of fractions 
B_{u,d}^{(*)} B_{u,d}^{(*)}(π(π))  f_{u,d} = 0.761 +0.027 −0.029  
B_{s}^{(*)} B_{s}^{(*)}  f_{s} = 0.200 +0.030 −0.031  f_{s} / f_{u,d} = 0.263 +0.052 −0.044 
no open bottomness  f_{noB} = 0.039 +0.050 −0.004 
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}) = 0.101 ± 0.008  
b baryons  f(bbaryon) = 0.085 ± 0.011  +0.074  
B^{0} or B^{+}  f(B_{d}) = f(B_{u}) = 0.407 ± 0.007  −0.632  −0.819 
B_{s} / (B^{0} or B^{+}) ratio  f(B_{s})/f(B_{d}) = 0.249 ± 0.023 
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}) = 0.115 ± 0.013  
b baryons  f(bbaryon) = 0.197 ± 0.046  −0.419  
B^{0} or B^{+}  f(B_{d}) = f(B_{u}) = 0.344 ± 0.021  +0.139  −0.958 
B_{s} / (B^{0} or B^{+}) ratio  f(B_{s})/f(B_{d}) = 0.335 ± 0.041 
χ(Tevatron) = 0.147 ± 0.011  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}) = 0.104 ± 0.005  
b baryons  f(bbaryon) = 0.089 ± 0.013  −0.240  
B^{0} or B^{+}  f(B_{d}) = f(B_{u}) = 0.404 ± 0.006  −0.160  −0.920 
B_{s} / (B^{0} or B^{+}) ratio  f(B_{s})/f(B_{d}) = 0.256 ± 0.014 
χ = 0.1259 ± 0.0042  LEP average from LEP EW WG 
χ = 0.147 ± 0.011  Tevatron average 
χ = 0.1284 ± 0.0069  Weighted average of above two, with error rescaled by factor 1.8 according to PDG prescription 
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