In the parameterization of Caprini et al. [Nucl. Phys. B530, 153
(1998)], the decay B -> D*lnu is described by four
quantities: etaEW F(1) |Vcb|, rho2,
R1 and R2. The following average is the result
of a four-dimensional global fit of these four parameters to the
measurements listed below. The values reported for each experiment have been
rescaled to the most recent values of the external parameters (B
lifetimes, D meson branching fractions) and to the values of
R1 and R2 found by the global fit,
R1(1)=1.406 +/- 0.033 and R2(1)=0.853 +/-
0.020. The fit assumes isospin symmetry.
Experiment | etaEW F(1) |Vcb| (rescaled) [10-3] | rho2 (rescaled) | Correlation (stat/syst/total) | Parameters | Remarks |
---|---|---|---|---|---|
ALEPH | 31.23 +/- 1.80 +/- 1.30 | 0.493 +/- 0.228 +/- 0.144 | 0.94/0.67/0.85 | input parameters | Phys.Lett.B395:373-387,1997 |
CLEO | 39.94 +/- 1.23 +/- 1.62 | 1.367 +/- 0.085 +/-0.086 | 0.91/0.83/0.86 | input parameters | Phys.Rev.Lett.89:081803,2002 |
OPAL excl | 36.50 +/- 1.60 +/- 1.49 | 1.234 +/- 0.212 +/- 0.145 | 0.95/0.45/0.75 | input parameters | Phys.Lett.B482:15-30,2000 |
OPAL partial reco | 37.14 +/- 1.19 +/- 2.36 | 1.152 +/- 0.145 +/- 0.294 | 0.77/0.78/0.78 | input parameters | Phys.Lett.B482:15-30,2000 |
DELPHI partial reco | 35.32 +/- 1.40 +/- 2.33 | 1.174 +/- 0.126 +/- 0.377 | 0.94/0.68/0.70 | input parameters | Phys.Lett.B510:55-74,2001 |
DELPHI excl | 36.10 +/- 1.70 +/- 1.97 | 1.081 +/- 0.142 +/- 0.152 | 0.89/0.80/0.84 | input parameters | Eur.Phys.J.C33:213-232,2004 |
BELLE | 34.60 +/- 0.17 +/- 1.02 | 1.212 +/- 0.034 +/- 0.009 | 0.63/-0.11/0.07 | input parameters | Phys.Rev.D82:112007,2010 |
BABAR excl | 33.94 +/- 0.30 +/- 0.99 | 1.185 +/- 0.048 +/- 0.029 | 0.27/0.02/0.08 | input parameters | Phys.Rev.D77:032002,2008 |
BABAR D*0 | 35.22 +/- 0.59 +/- 1.33 | 1.128 +/- 0.058 +/- 0.055 | 0.90/0.37/0.50 | input parameters | Phys.Rev.Lett.100:231803,2008 |
BABAR global fit | 35.76 +/- 0.20 +/- 1.10 | 1.193 +/- 0.020 +/- 0.061 | 0.38/0.85/0.81 | input parameters | Phys.Rev.D79:012002,2009 |
Average | 35.81 +/- 0.11 +/- 0.44 | 1.207 +/- 0.015 +/- 0.021 | 0.49/0.32/0.32 | chi2/dof = 30.0/23 (CL = 0.150) | eps 1 pdf 1 eps 2 pdf 2 |
These branching fractions have been calculated from the values of
etaEW F(1) |Vcb|, rho2, R1
and R2 obtained by the global four-dimensional fit described above.
Experiment | BF (rescaled) [%] | Remarks |
---|---|---|
ALEPH | 5.35 +/- 0.25 +/- 0.31 | Phys.Lett.B395:373-387,1997 |
CLEO | 5.62 +/- 0.18 +/- 0.26 | Phys.Rev.Lett.89:081803,2002 |
OPAL excl | 5.05 +/- 0.19 +/- 0.42 | Phys.Lett.B482:15-30,2000 |
OPAL partial reco | 5.46 +/- 0.25 +/- 0.52 | Phys.Lett.B482:15-30,2000 |
DELPHI partial reco | 4.88 +/- 0.13 +/- 0.72 | Phys.Lett.B510:55-74,2001 |
DELPHI excl | 5.35 +/- 0.20 +/- 0.37 | Eur.Phys.J.C33:213-232,2004 |
BELLE | 4.56 +/- 0.03 +/- 0.26 | Phys.Rev.D82:112007,2010 |
BABAR excl | 4.54 +/- 0.04 +/- 0.25 | Phys.Rev.D77:032002,2008 |
BABAR D*0 | 4.97 +/- 0.07 +/- 0.34 | Phys.Rev.Lett.100:231803,2008 |
BABAR global fit | 4.95 +/- 0.02 +/- 0.20 | Phys.Rev.D79:012002,2009 |
Average | 4.93 +/- 0.01 +/- 0.11 | chi2/dof = 30.0/23 (CL = 0.150) eps pdf |
The average BF is the result of a one-dimensional fit to the
measurements listed.
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
CLEO | 6.60 +/- 0.20 +/- 0.39 | input parameters | Phys.Rev.D67:032001,2003 |
BABAR tagged | 5.74 +/- 0.15 +/- 0.30 | input parameters | Phys.Rev.Lett.100:151802,2008 |
BABAR untagged | 5.36 +/- 0.08 +/- 0.40 | input parameters | Phys.Rev.Lett.100:231803,2008 |
BABAR global fit | 5.42 +/- 0.02 +/- 0.21 | input parameters | Phys.Rev.D79:012002,2009 |
Average | 5.69 +/- 0.02 +/- 0.19 | chi2/dof = 9.0/3 (CL = 0.0294) | eps pdf |
In the parameterization of Caprini et al. [Nucl. Phys. B530, 153
(1998)], the decay B -> Dlnu is described by two quantities:
etaEW G(1) |Vcb| and rho2. The
following average is the result of a two-dimensional global fit of
these two parameters to the measurements listed below. The values
reported for each experiment have been rescaled to the most recent
values of the external parameters (B lifetimes, D meson branching
fractions). The fit assumes isospin symmetry.
Experiment | etaEW G(1) |Vcb| (rescaled) [10-3] | rho2 (rescaled) | Correlation (stat/syst/total) | Parameters | Remarks |
---|---|---|---|---|---|
ALEPH | 38.66 +/- 11.80 +/- 5.19 | 0.942 +/- 0.980 +/- 0.272 | 0.98/1.00/0.97 | input parameters | Phys.Lett.B395:373-387,1997 |
CLEO | 44.88 +/- 5.96 +/- 3.25 | 1.270 +/- 0.220 +/- 0.119 | 0.95/0.40/0.83 | input parameters | Phys.Rev.Lett.82:3746,1999 |
BELLE | 40.96 +/- 4.39 +/- 5.03 | 1.120 +/- 0.190 +/- 0.111 | 0.96/0.19/0.62 | input parameters | Phys.Lett.B526:258-268,2002 |
BABAR global fit | 43.25 +/- 0.80 +/- 2.07 | 1.201 +/- 0.040 +/- 0.057 | 0.96/0.86/0.85 | input parameters | Phys.Rev.D79:012002,2009 |
BABAR tagged | 42.54 +/- 1.88 +/- 1.02 | 1.177 +/- 0.088 +/- 0.057 | 0.95/0.44/0.82 | input parameters | Phys.Rev.Lett.104:011802,2010 |
Average | 42.65 +/- 0.72 +/- 1.35 | 1.185 +/- 0.035 +/- 0.041 | 0.96/0.79/0.82 | chi2/dof = 0.5/8 (CL = 1.000) | eps 1 pdf 1 eps 2 pdf 2 |
These branching fractions have been calculated from the values of
etaEW G(1) |Vcb| and rho2 obtained by
the global two-dimensional fit described above.
Experiment | BF (rescaled) [%] | Remarks |
---|---|---|
ALEPH | 2.15 +/- 0.18 +/- 0.45 | Phys.Lett.B395:373-387,1997 |
CLEO | 2.19 +/- 0.16 +/- 0.35 | Phys.Rev.Lett.82:3746,1999 |
BELLE | 2.08 +/- 0.12 +/- 0.52 | Phys.Lett.B526:258-268,2002 |
BABAR global fit | 2.16 +/- 0.03 +/- 0.13 | Phys.Rev.D79:012002,2009 |
BABAR tagged | 2.14 +/- 0.11 +/- 0.08 | Phys.Rev.Lett.104:011802,2010 |
Average | 2.13 +/- 0.03 +/- 0.09 | chi2/dof = 0.5/8 (CL = 1.000) eps pdf |
The average BF is the result of a one-dimensional fit to the
measurements listed.
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
ALEPH | 2.28 +/- 0.18 +/- 0.35 | input parameters | Phys.Lett.B395:373-387,1997 |
CLEO | 2.13 +/- 0.13 +/- 0.15 | input parameters | Phys.Rev.Lett.82:3746,1999 |
BELLE | 2.11 +/- 0.12 +/- 0.39 | input parameters | Phys.Lett.B526:258-268,2002 |
BABAR | 2.22 +/- 0.11 +/- 0.12 | input parameters | Phys.Rev.Lett.100:151802,2008 |
Average | 2.19 +/- 0.06 +/- 0.10 | chi2/dof = 0.2/3 (CL = 0.973) | eps pdf |
The average BF is the result of a one-dimensional fit to the
measurements listed.
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
CLEO | 2.20 +/- 0.13 +/- 0.17 | input parameters | Phys.Rev.Lett.82:3746,1999 |
BABAR | 2.29 +/- 0.09 +/- 0.09 | input parameters | Phys.Rev.Lett.100:151802,2008 |
Average | 2.27 +/- 0.07 +/- 0.08 | chi2/dof = 0.1/1 (CL = 0.721) | eps pdf |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
ALEPH | 0.440+/- 0.098+/- 0.068 | input parameters | Z.Phys. C 73:601,1997 [Z.Phys.C73] |
OPAL | 0.578 +/- 0.210+/- 0.101 | input parameters | Eur.Phys. J.C 30:467,2003 [hep-ex/0301018] |
CLEO | 0.354 +/- 0.085+/- 0.056 | input parameters | Phys.Rev.Lett.80:4127,1998 [hep-ex/9708035] |
D0 | 0.215 +/- 0.018+/- 0.035 | input parameters | Phys.Rev.Lett.95:171803,1995 [hep-ex/0507046] |
BELLE tagged B+ | 0.443 +/- 0.070+/- 0.059 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BELLE tagged B0 | 0.612 +/- 0.200+/- 0.077 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR tagged | 0.278 +/- 0.030+/- 0.028 | input parameters | Phys.Rev.Lett.101:261802,2008 [arXiv:0808.0528 [hep-ex]] |
BABAR untagged B+ | 0.295 +/- 0.017+/- 0.016 | input parameters | Phys.Rev.Lett.103:051803,2009 [arXiv:0808.0333 [hep-ex]] |
BABAR untagged B0 | 0.299 +/- 0.026+/- 0.027 | input parameters | Phys.Rev.Lett.103:051803,2009 [arXiv:0808.0333 [hep-ex]] |
Average | 0.285 +/- 0.011 +/- 0.14 | chi2/dof = 13/8 (CL = 11.1%) | eps pdf gif |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
CLEO | 0.056 +/- 0.066+/- 0.011 | input parameters | Phys.Rev.Lett.80:4127,1998 [hep-ex/9708035] |
D0 | 0.087 +/- 0.018+/- 0.020 | input parameters | Phys.Rev.Lett.95:171803,2005 [hep-ex/0507046] |
BELLE tagged | 0.190 +/- 0.060+/- 0.025 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR tagged | 0.076 +/- 0.013 +/- 0.009 | input parameters | Phys.Rev.Lett.101:261802,2008 [arXiv:0808.0528 [hep-ex]] |
BABAR untagged B+ | 0.090 +/- 0.009+/- 0.007 | input parameters | Phys.Rev.Lett.103:051803,2009 [arXiv:0808.0333 [hep-ex]] |
BABAR untagged B0 | 0.067 +/- 0.010+/- 0.004 | input parameters | Phys.Rev.Lett.103:051803,2009 [arXiv:0808.0333 [hep-ex]] |
Average | 0.078 +/- 0.007 +- 0.004 | chi2/dof = 5.6/5 (CL = 34.7%) | eps pdf gif |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
DELPHI | 0.74 +/- 0.17+/- 0.18 | input parameters | Eur.Phys.J.C45:35-59,2006 [hep-ex/0510024] |
BELLE tagged | -0.03 +/- 0.06+/- 0.07 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR tagged | 0.26 +/- 0.04 +/- 0.04 | input parameters | Phys.Rev.Lett.101:261802,2008 [arXiv:0808.0528 [hep-ex]] |
Average | 0.13 +/- 0.03 +/- 0.02 | chi2/dof = 18/2 (CL = 0.001) | eps pdf gif |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
BELLE tagged B+ | 0.25 +/- 0.04+/- 0.06 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BELLE tagged B0 | 0.23 +/- 0.08+/- 0.06 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR tagged | 0.32 +/- 0.04 +/- 0.05 | input parameters | Phys.Rev.Lett.101:261802, 2008 [arXiv:0808.0528 [hep-ex]] |
Average | 0.29 +/- 0.03 +/- 0.04 | chi2/dof = 0.61/2 (CL = 74%) | eps pdf gif |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
BELLE | 0.42+/- 0.04+/- 0.05 | input parameters | [Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR | 0.42+/- 0.06+/- 0.03 | input parameters | [Phys.Rev.Lett.100:151802, 2008 [arXiv:0712.3503 [hep-ex]] |
Average | 0.42+/- 0.05 | chi2/dof = 0.01 (CL = 0.90) | eps pdf gif |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
BELLE | 0.68+/- 0.08+/- 0.07 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR | 0.57+/- 0.05+/- 0.04 | input parameters | Phys.Rev.Lett.100:151802, 2008 [arXiv:0712.3503 [hep-ex]] |
Average | 0.60+/- 0.06 | chi2/dof = 0.5 (CL = 0.52) | eps pdf gif |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
BELLE | 0.43+/- 0.07+/- 0.05 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR | 0.41+/- 0.08+/- 0.03 | input parameters | Phys.Rev.Lett.100:151802, 2008 [arXiv:0712.3503 [hep-ex]] |
Average | 0.42+/- 0.06 | chi2/dof = 0.04 (CL = 0.85) | eps pdf gif |
Experiment | BF (rescaled) [%] | Parameters | Remarks |
---|---|---|---|
BELLE | 0.58+/- 0.21+/- 0.07 | input parameters | Phys.Rev.D77:091503, 2008 [arXiv:0711.3252 [hep-ex]] |
BABAR | 0.46+/- 0.08+/- 0.04 | input parameters | Phys.Rev.Lett.100:151802, 2008 [arXiv:0712.3503 [hep-ex]] |
Average | 0.48+/- 0.08 | chi2/dof = 0.25 (CL = 0.62) | eps pdf gif |
We use the predictions of the semileptonic width, the moments of the lepton energy spectrum and the moments of the hadronic mass spectrum squared in B -> Xclnu for different lepton energy thresholds obtained in JHEP 1109 (2011) 055.
These OPE expressions are fit to these B -> Xclnu moment measurements. The symbol 'n' indicates the order of the moment while 'c' indicates the value of the minimum lepton energy (in GeV). The n=0 lepton moment is the partial branching fraction of B -> Xclnu.
Experiment | Hadron moments <MnX> | Lepton moments <Enl> | References |
---|---|---|---|
BaBar | n=2 c=0.9,1.1,1.3,1.5 n=4 c=0.8,1.0,1.2,1.4 n=6 c=0.9,1.3 [1] |
n=0 c=0.6,1.2,1.5 n=1 c=0.6,0.8,1.0,1.2,1.5 n=2 c=0.6,1.0,1.5 n=3 c=0.8,1.2 [1,2] |
[1] Phys.Rev. D81
(2010) 032003 [2] Phys.Rev. D69 (2004) 111104 |
Belle | n=2 c=0.7,1.1,1.3,1.5 n=4 c=0.7,0.9,1.3 [3] |
n=0 c=0.6,1.4 n=1 c=1.0,1.4 n=2 c=0.6,1.4 n=3 c=0.8,1.2 [4] |
[3]
Phys.Rev. D75 (2007) 032005 [4] Phys.Rev. D75 (2007) 032001 |
CDF | n=2 c=0.7 n=4 c=0.7 [5] |
. | [5] Phys.Rev. D71 (2005) 051103 |
CLEO | n=2 c=1.0,1.5 n=4 c=1.0,1.5 [6] |
. | [6] Phys.Rev. D70 (2004) 032002 |
DELPHI | n=2 c=0.0 n=4 c=0.0 n=6 c=0.0 [7] |
n=1 c=0.0 n=2 c=0.0 n=3 c=0.0 [7] |
[7] Eur.Phys.J. C45 (2006) 35-59 |
The global fit determines the semileptonic B meson branching fraction, the quark masses mb and mc and the OPE parameters mu2pi, mu2G, rho3D and rho3LS. mu2G and rho3LS are constrained to (0.35 +/- 0.07) GeV2 and (-0.15 +/- 0.10) GeV3, respectively. The c-quark mass (defined in the MSbar scheme) is fixed to (0.986 +/- 0.013) GeV from Phys.Rev. D80 (2009) 074010. Refer to Phys.Rev. D89 (2014) 014022 for more details on the fit. From these parameters |Vcb| is calculated assuming an average B meson lifetime of (1.579 +/- 0.005) ps. The chi2 of the fit is 14.6 for 50-7 degrees of freedom.
Br(B -> Xclnu) (%) | |Vcb| (10-3) | mbkin (GeV) | mu2pi (GeV2) | |
---|---|---|---|---|
10.65 +/- 0.16 | 42.46 +/- 0.88 | 4.541 +/- 0.023 | 0.414 +/- 0.078 | details |
The following plots show the result of the fit in terms of the partial branching fraction (e0), the lepton energy (e1, e2, e3) and the hadronic mass squared (h1, h2, h3) moments. In all plots, the grey band is the theory prediction with total theory error. BaBar data are shown by circles, Belle by squares and other experiments (DELPHI, CDF, CLEO) by triangles. Filled symbols mean that the point was used in the fit. Open symbols are measurements that were not used in the fit.
Moment | |
---|---|
e0 | eps pdf |
e1 | eps pdf |
e2 | eps pdf |
e3 | eps pdf |
h1 | eps pdf |
h2 | eps pdf |
h3 | eps pdf |
In the |Vub| averages only measurements for which the correlation is known are considered. They are either independent measurements or correlated measurements for which the correlation among the analyses is available (eg the BaBar B-Reco analyses). If the analyses are correlated but the correlation is not known, the analysis with the smallest error is considered.
No attempt is made to average values for |Vub| from the different theoretical models, but the results are presented independently per each scheme.
The procedure for performing the average is documented in [arXiv:0808.1297]
The input files for the average are linked in the tables with the averages. To summarize briefly, all theoretical uncertainties are considered to be correlated, as are the uncertainties on the modeling of b -> clnu and b -> ulnu decays. Experimental uncertainties (particle identification, reconstruction efficiencies, etc.) are taken as correlated amongst measurements from the same experiment, but not correlated across experiments. Statistical correlations are also taken into account, when available.
The errors in the tables are experimental (statistical and systematic) and external (theoretical and HQ parameter uncertainties). The average B lifetime used is 1.582 ps. Final state radiation is included in all the measurements.
The input parameters for the different modes are coming from the global fit in the kinetic scheme, translated to the scheme needed per each model. For consistency among all the measurements, we choose the results coming from the fits to the b->clnu moments, with a constraint on the charm quark mass.
The |Vub| values are obtained using the HQE input parameter:
|Vub | (BLNP) | ||||
Experiment | Value [10-3] | Parameters | References | Remarks |
---|---|---|---|---|
CLEO (Ee) | 4.28 ± 0.50 + 0.31 - 0.36 | input | Phys.Rev.Lett.88:231803,2002 [arXiv:hep-ex/0202019v1] |
2.1 < Ee < 2.6 |
BELLE sim. ann. (mX, q2) | 4.49 ± 0.47 + 0.28 - 0.30 | input | Phys.Rev.Lett.92:101801,2004 [arXiv:hep-ex/0311048v2] |
Cut on mX<1.7 GeV, q2>8GeV2 tag with annealing method |
BELLE (Ee) | 4.93 ± 0.46 + 0.27 - 0.29 | input | Phys.Lett.B621:28-40 (2005) [arXiv:hep-ex/0504046v2] |
1.9 < Ee < 2.6 |
BABAR (Ee) | 4.54 ± 0.26 + 0.27 - 0.33 | input | Phys.Rev.D73:012006,2006 [arXiv:hep-ex/0509040v2] |
2.0 < Ee < 2.6 |
BABAR (Ee, shmax) | 4.53 ± 0.22 + 0.33 - 0.38 | input | preliminary update (EPS2013) of [arXiv:hep-ex/0506036v3] |
Ee > 2.0, shmax < 3.5 |
BELLE multivariate (p*) | 4.49 ± 0.27 + 0.20 - 0.22 | input | Phys.Rev.Lett.104:021801,2010 [arXiv:0907.0379v1 [hep-ex]] |
BRECO tag; multivariate analysis. Cut on lepton energy at 1 GeV |
BABAR (mX<1.55) | 4.30 ± 0.20 + 0.28 - 0.27 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX< 1.55 GeV |
BABAR (mX<1.7) | 4.04 ± 0.22 + 0.23 - 0.23 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX<1.7 GeV |
BABAR (mX<1.7, q2>8) | 4.30 ± 0.23 + 0.26 - 0.28 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at mX<1.7 GeV, q2>8 GeV2 |
BABAR (P+<0.66) | 4.15 ± 0.25 + 0.28 - 0.27 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at P+<0.66 GeV |
BABAR (p*>1GeV) | 4.32 ± 0.24 + 0.19 - 0.21 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit (mX, q2), cut at p*>1GeV |
BABAR (p*>1.3GeV) | 4.32 ± 0.27 + 0.20 - 0.21 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit p*, cut at p*>1.3GeV |
Average ± exp + th. - th. | 4.45 ± 0.16 + 0.21 - 0.22 | χ2/dof = 9.00/11 (CL = 0.62) |
Plots: eps pdf gif | mb input from global fit in the kinetic scheme |
The full breakdown of the uncertainties on the average |Vub| above is (all errors quoted in percent):
positive errors: +2.0stat +1.7exp +1.2b2c model +1.9b2u model +2.6HQE param +0.1SF func +0.6sub SF +0.0WA +3.8matching = +5.8tot
negative errors: -2.1stat -1.8exp -1.2b2c model -1.8b2u model -2.7HQE param -0.3SF func -0.6sub SF -1.4WA -3.8matching = -5.9tot
where the fractions correspond to the statistical error (stat), the experimental systematics (exp), the modeling, e.g. branching fractions for exclusive decays, of b -> c l nu and b -> u l nu decays (b2c model and b2u model, respectively), the HQE parameters mb and μπ2 (HQE param), the functional form of the SF (ie the variation from the exponential to the Gaussian form of the SF, SF func), the subleading shape functions (sub SF), the variation of the matching scales (matching), and the Weak Annihilation (WA). No uncertainty is assigned for possible duality violations. The quoted experimental error in the table above corresponds to the statistical, experimental systematic and the b -> c l nu and b -> u l nu modeling errors. The other uncertainties contribute to the theoretical error.
It should be noted that the above results and averages do not include NNLO corrections. A paper By Neubert and collaborators (arxiv:0909.1609 [hep-ph]) suggests that these have non-negligible impact on the determination of Vub. Unfortunately, the numerical implementation of those corrections is not in a form that would be immediately suitable for public use by HFAG. Moreover, those results only include the NNLO corrections to the leading term in the 1/m_b expansion for the shape-function region. They neglect "kinematic" power corrections that become less and less suppressed as the phase space cuts are less restrictive. Therefore, while this subset of NNLO corrections are presumably dominant and important for restrictive cuts like P+<0.66 GeV cut, this should not be the case for less restrictive cuts like p* > 1.0 GeV. Therefore, we continue using the NLO code and we remark that for restrictive cuts one may expect that the NNLO corrections induce order 5.8 % upward shifts in Vub.
The |Vub| values are obtained using the HQE input parameter:
|Vub| (DGE) | ||||
Experiment | Value [10-3] | Parameters | References | Remarks |
---|---|---|---|---|
CLEO (Ee) | 3.90 ± 0.45 + 0.26 - 0.28 | input | Phys.Rev.Lett.88:231803,2002 [arXiv:hep-ex/0202019v1] |
2.1 < Ee < 2.6 |
BELLE sim. ann. (mX, q2) | 4.46 ± 0.47 + 0.20 - 0.22 | input | Phys.Rev.Lett.92:101801,2004 [arXiv:hep-ex/0311048v2] |
Cut on mX<1.7 GeV, q2>8GeV2 tag with annealing method |
BELLE (Ee) | 4.85 ± 0.45 + 0.21 - 0.25 | input | Phys.Lett.B621:28-40 (2005) [arXiv:hep-ex/0504046v2] |
1.9 < Ee < 2.6 |
BABAR (Ee) | 4.34 ± 0.25 + 0.23 - 0.25 |
input | Phys.Rev.D73:012006,2006 [arXiv:hep-ex/0509040v2] |
2.0 < Ee < 2.6 |
BABAR (Ee, shmax) | 4.17 ± 0.20 + 0.28 - 0.29 | input | preliminary update (EPS2013) of |
Ee > 2.0 shmax <3.5 |
BELLE multivariate (p*) | 4.63 ± 0.28 + 0.13 - 0.13 | input | Phys.Rev.Lett.104:021801,2010 [arXiv:0907.0379v1 [hep-ex]] |
BRECO tag; multivariate analysis. Cut on lepton energy at 1 GeV |
BABAR (mX<1.55) | 4.53 ± 0.21 + 0.24 - 0.22 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX< 1.55 GeV |
BABAR (mX<1.7) | 4.26 ± 0.24 + 0.26 - 0.24 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX<1.7 GeV |
BABAR (mX<1.7, q2>8) | 4.27 ± 0.22 + 0.20 - 0.20 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at mX<1.7 GeV, q2>8 GeV2 |
BABAR (P+<0.66) | 4.24 ± 0.26 + 0.37 - 0.32 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at P+<0.66 GeV |
BABAR (mX, q2 fit, p*>1GeV) | 4.46 ± 0.24 + 0.13 - 0.13 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit (mX, q2), cut at p*>1GeV |
BABAR (p*>1.3GeV) | 4.44 ± 0.27 + 0.15 - 0.14 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit p*, cut at p*>1.3GeV |
Average ± exp + theory - theory | 4.52 ±0.16 + 0.15 - 0.16 | χ2/dof = 9.46/11 (CL = 0.58) |
Plots: eps pdf gif | mb input from global fit in the kinetic scheme |
The full breakdown of the uncertainties on the average |Vub| above is (all errors quoted in percent):
positive errors: +1.8stat +1.7exp +1.3b2c model +2.1b2u model +0.5alpha_s R_CUT +3.2mb +0.0WA +0.5DGE theory =+4.8tot
negative errors: -1.8stat -1.7exp -1.3b2c model -1.9b2u model -0.5alpha_s R_CUT -3.0mb -1.9WA -0.3DGE theory =-5.0tot
where the fractions correspond to the statistical error (stat), the experimental systematics (exp), the modeling, e.g. branching fractions for exclusive decays, of the b -> c l nu and b -> u l nu decays (b2c model and b2u model, respectively), the effect of the alphas uncertainty on R_CUT (alpha_s R_CUT), the effect of the uncertainty on mb on the prediction of the event fraction and the total rate (mb), the Weak Annihilation (WA) and from the change and variation of scale of the matching scheme (DGE theory). The quoted experimental error in the table above corresponds to the statistical, experimental systematic and the b -> c l and b -> u l nu modeling errors. The other uncertainties contribute to the theoretical error.
The |Vub| values are obtained using the HQE input parameters:
The BABAR (Ee, shmax) analysis is not included in the average, since the Ee, shmax cuts are not yet implemented in the model.
|Vub| (GGOU) | ||||
Experiment | Value [10-3] | Parameters | References | Remarks |
---|---|---|---|---|
CLEO (Ee) | 4.21 ± 0.49 +0.23 -0.33 | input | Phys.Rev.Lett.88:231803,2002 [arXiv:hep-ex/0202019v1] |
2.1 < Ee < 2.6 |
BELLE sim. ann. (mX, q2) | 4.50 ± 0.47 +0.28 -0.31 | input | Phys.Rev.Lett.92:101801,2004 [arXiv:hep-ex/0311048v2] |
Cut on mX<1.7 GeV, q2>8GeV2 tag with annealing method |
BELLE (Ee) | 4.93 ± 0.46 +0.17 -0.22 | input | Phys.Lett.B621:28-40 (2005) [arXiv:hep-ex/0504046v2] |
1.9 < Ee < 2.6 |
BABAR (Ee) | 4.50 ± 0.26 +0.18 -0.25 | input | Phys.Rev.D73:012006,2006 [arXiv:hep-ex/0509040v2] |
2.0 < Ee < 2.6 |
BELLE multivariate (p*) | 4.60 ± 0.27 + 0.10 - 0.11 | input | Phys.Rev.Lett.104:021801,2010 [arXiv:0907.0379v1 [hep-ex]] |
BRECO tag; multivariate analysis. Cut on lepton energy at 1 GeV |
BABAR (mX<1.55) | 4.29 ± 0.20 + 0.21 - 0.22 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX< 1.55 GeV |
BABAR (mX<1.7) | 4.09 ± 0.23 + 0.18 - 0.19 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX<1.7 GeV |
BABAR (mX<1.7, q2>8) | 4.32 ± 0.23 + 0.27 - 0.30 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at mX<1.7 GeV, q2>8 GeV2 |
BABAR (P+<0.66) | 4.24 ± 0.26 + 0.32 - 0.32 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at P+<0.66 GeV |
BABAR (mX, q2 fit, p*>1GeV) | 4.42 ± 0.24 + 0.09 - 0.11 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit (mX, q2), cut at p*>1GeV |
BABAR (p*>1.3GeV) | 4.41 ± 0.27 + 0.10 - 0.12 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit p*, cut at p*>1.3GeV |
Average ± exp + theory - theory | 4.51 ± 0.16 + 0.12 - 0.15 | χ2/dof = 8.80/10 (CL=0.55) |
Plots: eps pdf gif | mb input from global fit in the kinetic scheme |
The full breakdown of the uncertainties on the average |Vub| above is (all errors quoted in percent):
positive errors: +1.9stat +1.7exp +1.3b2c model +1.9b2u model +1.6par. +1.5pert. +1.4q2* +0.0WA +0.2ff =+4.3tot
negative errors: -1.9stat -1.7exp -1.3b2c model -1.9b2u model -1.6par. -1.5pert. -1.4q2* -2.0WA -0.2ff =-4.8tot
where the fractions correspond to the statistical error (stat), the experimental systematics (exp), the modeling, e.g. branching fractions for exclusive decays, of the b -> c l nu and b -> u l nu decays (b2c model and b2u model, respectively), the value of alpha_s, mb and other non-perturbative parameters (par.), higher order perturbative and non-perturbative corrections (pert.), the modelling of the q2 tail and choice of the scale q2* (q2*), the WA matrix element (WA), the functional form of the distribution functions (ff).
The |Vub| values are obtained using the HQE input parameter:
|Vub| (ADFR) | ||||
Experiment | Value [10-3] | Parameters | References | Remarks |
---|---|---|---|---|
CLEO (Ee) | 3.44 ± 0.40 + 0.16 - 0.16 | input | Phys.Rev.Lett.88:231803,2002 [arXiv:hep-ex/0202019v1] |
2.1 < Ee < 2.6 |
BELLE sim. ann. (mX, q2) | 3.94 ± 0.41 + 0.17 - 0.17 | input | Phys.Rev.Lett.92:101801,2004 [arXiv:hep-ex/0311048v2] |
Cut on mX<1.7 GeV, q2>8GeV2 tag with annealing method |
BELLE (Ee) | 4.50 ± 0.42 + 0.20 - 0.20 | input | Phys.Lett.B621:28-40 (2005) [arXiv:hep-ex/0504046v2] |
1.9 < Ee < 2.6 |
BABAR (Ee) | 3.94 ± 0.22 + 0.20 - 0.19 | input | Phys.Rev.D73:012006,2006 [arXiv:hep-ex/0509040v2] |
2.0 < Ee < 2.6 |
BABAR (Ee, shmax) | 3.64 ± 0.18 + 0.17 - 0.17 | input | preliminary update (EPS2013) of [arXiv:hep-ex/0506036v3] |
Ee > 2, shmax < 3.5 |
BELLE multivariate (p*) | 4.52 ± 0.30 + 0.19 - 0.19 | input | Phys.Rev.Lett.104:021801,2010 [arXiv:0907.0379v1 [hep-ex]] |
BRECO tag; multivariate analysis. Cut on lepton energy at 1 GeV |
BABAR (mX<1.55) | 3.84 ± 0.18 + 0.19 - 0.19 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX< 1.55 GeV |
BABAR (mX<1.7) | 3.76 ± 0.21 + 0.18 - 0.17 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut on hadronic mass mX<1.7 GeV |
BABAR (mX<1.7,q2>8) | 3.76 ± 0.20 + 0.17 - 0.16 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at mX<1.7 GeV, q2>8 GeV2 |
BABAR (P+<0.66) | 3.59 ± 0.22 + 0.19 - 0.18 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Cut at P+<0.66 GeV |
BABAR ((mX-q2) fit, p*>1) | 4.35 ± 0.24 + 0.18 - 0.18 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit (mX, q2), cut at p*>1GeV |
BABAR (p*>1.3) | 4.30 ± 0.27 + 0.19 - 0.18 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
BRECO tag. Fit p*, cut at p*>1.3GeV |
Average ± exp + theory - theory | 4.05 ± 0.13 + 0.18 - 0.11 | χ2/dof = 31.9/11 (CL = 0.001) |
Plots: eps pdf gif |
positive errors: +1.8stat +1.8exp +1.4b2c model +1.3b2u model +1.1alpha_s +2.0Vcb +0.7mb +0.4mc +0.8BF +3.5model =+5.4tot
negative errors: -1.8stat -2.0exp -1.4b2c model -1.3b2u model -1.0alpha_s -2.0Vcb -0.7mb -0.7mc -0.7BF -3.5model =-5.3tot
where the fractions correspond to the statistical error (stat), the experimental systematics (exp), the modeling, e.g. branching fractions for exclusive decays, of the b -> c l nu and b -> u l nu decays (b2c model and b2u model, respectively), the effect of the alphas uncertainty (alpha_s), the effect of the uncertainty on Vcb (Vcb), on the b-quark mass in the MS scheme (mb), on the c-quark mass in the MS scheme (mc), on the semileptonic BF (BF) and on the model (model). The quoted experimental error in the table above corresponds to the statistical, experimental systematic and the b -> c l and b -> u l nu modeling errors. The other uncertainties contribute to the theoretical error.
The |Vub| values are
obtained using the HQE input parameter:
obtained from a global fit in the 1S scheme
|Vub| (BLL) using the (mx-q2) analyses | ||||
Experiment | Value [10-3] | Parameters | References | Remarks |
---|---|---|---|---|
BELLE breco (mX, q2) | 5.01 ± 0.39 ± 0.32 | input | Phys.Rev.Lett.95:241801,2005 [hep-ex/0505088] |
mX-q2, BRECO tag |
BELLE sim. ann. (mX, q2) | 4.68 ± 0.49 ± 0.30 | input | Phys.Rev.Lett.92:101801,2004 [arXiv:hep-ex/0311048v2] |
mX - Q2, tag with annealing method |
BABAR (mX, q2) | 4.50 ± 0.24 ± 0.29 | input | arxiv:1112.0702v1 submitted to PRD [arXiv:1112.0702v1] |
mX-q2, BRECO tag |
Average ± exp ± theory | 4.62 ± 0.20 ± 0.29 | χ2/dof = 1.4/2 (CL = 0.50) |
Plots: eps pdf gif | HQE parameter input from b to c l nu and b to s gamma moments |
The full breakdown of the uncertainties on the average |Vub| above is (all errors quoted in percent):
positive errors: +3.3stat +3.0exp +1.6b2c model +1.1b2u model +3.0Strf +3.0Pert +2.5Sf +4.0H.O. = +7.7tot
negative errors: -3.3stat -3.0exp -1.6b2c model -1.1b2u model -3.0Strf -3.0Pert -2.5Sf -4.0H.O. = -7.7tot
where the fractions correspond to the statistical error (stat), the experimental systematics (exp), the modeling, e.g. branching fractions for exclusive decays, of b -> c l nu and b -> u l nu decays (b2c model and b2u model, respectively), the residual shape function effects (Strf), the higher order terms in the alphas expansion (Pert), the uncertainty on the b-quark mass (Sf), and the third order terms in the OPE expansion(H.O.). No uncertainty is assigned for possible duality violations.
Several years ago, M. Neubert (Phys.
Rev. D49, 4623 (1994) ) suggested that |Vub| could be
extracted by combining weighted integrals over the photon spectrum in
B->Xs gamma decays with integrals over the lepton momentum spectrum
near the kinematic endpoint in inclusive B->Xulnu decays decays. The
underlying assumption is that the QCD interactions affecting these two
processes are the same to leading order, and therefore ratios of decay
rates for the two processes have significantly lower sensitivity to the
choice of the shape-functions parameterization.
So far, there are two BABAR
measurements based on this suggestion to
extract |Vub| from charmless B-meson decays from
inclusive
distributions for different regions of phase space.
BABAR measured |Vub|
in inclusive decays using the
prescription of Leibovich, Low, and Rothstein (LLR),
Phys.Rev.D62:014010,2000 [arXiv:hep-ph/0001028v2],
and Phys.Lett.B486:86-91,2000 [arXiv:hep-ph/0005124v1],
that extracts |Vub| with reduced model dependence by
combining data of the hadronic mass spectrum from B->Xulnu decays
with that of the photon energy spectrum from B->Xs gamma decays
(Phys.Rev. D72 (2005) 052004
[arXiv:hep-ex/0508004v2]).
Using BABAR measurements of the
lepton momentum spectrum near the
kinematic endpoint, Phys.Rev. D73 (2006) 012006
[arXiv:hep-ex/0509040v2],
two different theoretical prescriptions were tried to extract |Vub|,
Phys.Rev.D76:114003,2007 [arXiv:hep-ph/0702072],
namely LLR (Phys.Rev. D61 (2000) 053006 [arXiv:hep-ph/9909404v2]])
and LNP, a calculation by Lange, Neubert and Paz (JHEP 0510 (2005) 084 [arXiv:hep-ph/0508178v2]
and JHEP 0601 (2006) 104 [arXiv:hep-ph/0511098v1]).
In the following, we provide a comparison of the results of the
different |Vub| extractions.
The errors on |Vub| are experimental and theoretical, respectively, for the first three results and experimental on B->Xulnu, experimental on B->Xsgamma, theoretical and due to |Vts| for the last two measurments.
Description | Vub [10-3] | Reference |
---|---|---|
HFAG Ave. (BLNP) | 4.40 ± 0.15 +0.19 - 0.21 | |
HFAG Ave. (DGE) | 4.45 ± 0.15+ 0.15 - 0.16 | |
HFAG Ave. (GGOU) | 4.39 ± 0.15 + 0.12 - 0.20 | |
HFAG Ave. (ADFR) | 4.03 ± 0.13 + 0.18 - 0.12 |
|
HFAG Ave. (BLL) | 4.62 ± 0.20 + 0.29 - 0.29 | |
BABAR (LLR) | 4.43 ± 0.45 ± 0.29 | Phys.Rev.Lett. 96 (2006) 221801 [arXiv:hep-ex/0601046v2] |
BABAR endpoint (LLR) | 4.28 ± 0.29 ± 0.29 ± 0.26 ± 0.28 | Phys.Rev.D76:114003,2007 [arXiv:hep-ph/0702072] |
BABAR endpoint (LNP) | 4.40 ± 0.30 ± 0.41 ± 0.23 | Phys.Rev.D76:114003,2007 [arXiv:hep-ph/0702072] |
A plot of this table is available in three formats: eps pdf gif
Experiment | BF [10-3] | Parameters | Remarks |
---|---|---|---|
BELLE Tagged | 1.96 +/- 0.17+/- 0.16 | input parameters | Phys.Rev.Lett.104, 021801 (2010) [arXiv:0907.0379 [hep-ex]] |
BABAR Tagged | 1.80 +/- 0.13+/- 0.15 | input parameters | Submitted to PRD [arXiv:1112.0702 [hep-ex]] |
Average | 1.86 +/- 0.10 +/- 0.14 | chi2/dof = 0.41/1 (CL = 52%) | eps pdf gif |
The measurements quoted here include both B0 and B+ decays. The average assumes equality of the semileptonic decays widths for these isospin-conjugate states, and is quoted for B0 decays.
Please note that the results of the untagged measurements by CLEO and BABAR are based on a combined analysis of B0 -> pi- l+ nu and B+ -> pi0 l+nu decays, assuming isospin symmetry.
Experiment / Mode | BF [10-4] | BF(q2<12 GeV2) [10-4] | BF(q2<16 GeV2) [10-4] | BF(q2>16 GeV2) [10-4] | Reference |
---|---|---|---|---|---|
BABAR had. tag: B+ -> pi0 l+ nu × 2 τ0/τ+ | 1.52 +/- 0.41 +/- 0.30 | 0.67 +/- 0.30 +/- 0.12 | 1.04 +/- 0.35 +/- 0.18 | 0.48 +/- 0.22 +/- 0.12 | Breco tag, Phys. Rev. Lett.97, 211801 (2006) [hep-ex/0607089] (input)(param) |
Belle had. tag: B+ -> pi0 l+ nu × 2 τ0/τ+ | 1.48 +/- 0.15 +/- 0.08 | 0.78 +/- 0.11 +/- 0.04 | 1.09 +/- 0.12 +/- 0.06 | 0.36 +/- 0.07 +/- 0.02 | Breco tag, Phys. Rev. D88, 032005 (2013) [arXiv:1306.2781 [hep-ex]] (input)(param) |
BABAR sl. tag: B+ -> pi0 l+ nu × 2 τ0/τ+ | 1.78 +/- 0.28 +/- 0.15 | 1.07 +/- 0.20 +/- 0.09 | 1.35 +/- 0.22 +/- 0.11 | 0.44 +/- 0.17 +/- 0.06 | SL tag, Phys. Rev. Lett 101, 081801 (2008) [arXiv:0805.2408] (input)(param) |
Belle sl. tag: B+ -> pi0 l+ nu × 2 τ0/τ+ | 1.41 +/- 0.26 +/- 0.15 | 0.71 +/- 0.17 +/- 0.08 | 1.05 +/- 0.22 +/- 0.12 | 0.37 +/- 0.15 +/- 0.04 | SL tag, Phys. Lett. B648, 139-148 (2007) [hep-ex/0604024] (input)(param) |
BABAR had. tag: B0 -> pi- l+ nu | 1.07 +/- 0.27 +/- 0.19 | 0.26 +/- 0.15 +/- 0.04 | 0.42 +/- 0.18 +/- 0.06 | 0.65 +/- 0.20 +/- 0.13 | Breco tag, Phys. Rev. Lett.97, 211801 (2006) [hep-ex/0607089] (input)(param) |
Belle had. tag: B0 -> pi- l+ nu | 1.49 +/- 0.09 +/- 0.07 | 0.81 +/- 0.06 +/- 0.04 | 1.06 +/- 0.07 +/- 0.05 | 0.45 +/- 0.05 +/- 0.02 | Breco tag, Phys. Rev. D88, 032005 (2013) [arXiv:1306.2781 [hep-ex]] (input)(param) |
BABAR sl. tag: B0 -> pi- l+ nu | 1.38 +/- 0.21 +/- 0.08 | 0.77 +/- 0.14 +/- 0.05 | 0.92 +/- 0.16 +/- 0.05 | 0.46 +/- 0.13 +/- 0.03 | SL tag, Phys. Rev. Lett 101, 081801 (2008) [arXiv:0805.2408] (input)(param) |
Belle sl. tag: B0 -> pi- l+ nu | 1.41 +/- 0.19 +/- 0.15 | 0.80 +/- 0.14 +/- 0.08 | 1.04 +/- 0.16 +/- 0.11 | 0.37 +/- 0.10 +/- 0.04 | SL tag, Phys. Lett. B648, 139-148 (2007) [hep-ex/0604024] (input)(param) |
CLEO untagged: B -> pi l nu | 1.38 +/- 0.15 +/- 0.11 | 0.69 +/- 0.12 +/- 0.07 | 0.97 +/- 0.13 +/- 0.09 | 0.41 +/- 0.08 +/- 0.04 | Untagged, Phys. Rev. Lett.99, 041802 (2007) [arXiv:hep-ex/0703041v2] (input)(param) |
BABAR untagged (6 q2 bins): B -> pi l nu | 1.41 +/- 0.05 +/- 0.08 | 0.88 +/- 0.04 +/- 0.05 | 1.10 +/- 0.04 +/- 0.06 | 0.32 +/- 0.02 +/- 0.03 | Untagged, Phys. Rev. D83, 032007 (2011) [arXiv:1005.3288v2 [hep/ex] ] (input)(param) |
BABAR untagged (12 q2 bins): B -> pi l nu | 1.44 +/- 0.04 +/- 0.06 | 0.83 +/- 0.03 +/- 0.04 | 1.08 +/- 0.04 +/- 0.05 | 0.37 +/- 0.02 +/- 0.02 | Untagged loose neutrino, Phys. Rev. D86, 092004 (2012) [arXiv:1201.1253 [hep/ex] ] (input)(param) |
Belle untagged: B0 -> pi- l+ nu | 1.48 +/- 0.04 +/- 0.07 | 0.82 +/- 0.03 +/- 0.04 | 1.09 +/- 0.03 +/- 0.05 | 0.40 +/- 0.02 +/- 0.02 | Untagged, Phys. Rev. D83, 071101 (2011) [arXiv:1012.0090 [hep-ex]] (input)(param) |
Average: B0 -> pi- l+ nu | 1.45 +/- 0.02 +/- 0.04 | 0.81 +/- 0.02 +/- 0.02 | 1.06 +/- 0.02 +/- 0.03 | 0.38 +/- 0.01 +/- 0.01 | Plots: eps pdf gif chi2/dof = 3.4/11 (CL = 0.98) |
The partial BFs quoted above along with theoretical calculations of the form factor normalization can be used to determine |Vub|. The |Vub| results obtained from the HFAG averages for the partial BFs combined with different form factor calculations are shown below. Note that the FNAL/MILC and HPQCD unquenched LQCD calculations are not entirely independent. We also do not use their quenched results as they are superseded by the unquenched results. The calculations by Ball-Zwicky and Khodjamirian et al. are based on light-cone sum rules. At this time we do not attempt to average the |Vub| results obtained with different calculations or select a best value.
The errors on |Vub| are experimental and theoretical.
FF calculation | q2 range | FF norm. (ps-1) | |Vub| [10-3] | Reference |
---|---|---|---|---|
Khodjamirian et al. | <12 GeV2 | 4.59 +1.00 -0.85 | 3.41 +/- 0.06 +0.37-0.32 | Phys. Rev. D83:094031 (2011) [arXiv:1103.2655 [hep/ph]] |
Ball-Zwicky | <16 GeV2 | 5.44 +/- 1.43 | 3.58 +/- 0.06 +0.59-0.40 | Phys. Rev. D71:014015 (2005) [hep-ph/0406232] |
HPQCD | >16 GeV2 | 2.02 +/- 0.55 | 3.52 +/- 0.08 +0.61-0.40 | Phys.Rev. D73, 074502 (2006), Erratum-ibid.D75:119906,2007 [hep-lat/0601021] |
FNAL/MILC | >16 GeV2 | 2.21 +0.47 -0.42 | 3.36 +/- 0.08 +0.37-0.31 | Phys. Rev. D79, 054507 (2009) [arXiv:0811.3640v3 [hep-lat]] |
A plot of this table is available in three formats: eps pdf gif
Consistent results are obtained using quenched Lattice QCD calculations (eg. arXiv:hep-lat/0011065).|Vub| can also be determined from a simultaneous fit of a B -> pi form factor parameterization to data and LQCD calculations. In contrast to the |Vub| determinations presented above, this fit makes use of the measured q2 spectra over the full q2 range. We choose the BCL parameterization (Bourrely, Caprini and Lellouch, Phys. Rev. D79, 013008 (2009) [arXiv:0807.2722v3 [hep-ph]]. A fit of the BCL parameterization with 3+1 parameters (3 parameters for the BCL parameterization: b0,b1,b2 and one parameter for |Vub| to be determined from the relative normalization of data and LQCD results) to the four most precise measurements of BABAR and Belle (BABAR untagged 6 q2 bins B0+B+, BABAR untagged 12 q2 bins B0+B+, Belle untagged B0, Belle had. tag B0) and the FNAL/MILC lattice predictions yields the following results:
|Vub| = (3.28 +- 0.29) × 10-3
b1/b0 = -1.02 +- 0.18
b2/b0 = -1.20 +- 0.57
For the product f+(0)|Vub| we obtain: f+(0)|Vub| = (0.923 +- 0.024) × 10-3.
The quoted errors are the combined experimental and theoretical errors obtained from the fit.
The probability of the fit is 0.053 (χ2/dof = 60.2/44).
Only 4 of the 12 LCQD points were used to avoid the high correlations between
neighboring points.
A plot of the fit result is available in three formats: eps pdf gif
The simultaneous fit to data and theory has also been performed with the most recent light-cone sum rule result for f+(0) (f+(0) = 0.261 +0.020-0.023 from A. Bharucha, JHEP 1205 (2012) 092 [arXiv:1203.1359 [hep-ph]]), i.e. a single theory point at q2 = 0 GeV2 is used instead of the FNAL/MILC results at high q2. This fit gives consistent results:
|Vub| = (3.53 +- 0.29) × 10-3
b1/b0 = -0.99 +- 0.20
b2/b0 = -1.28 +- 0.61
f+(0)|Vub| = (0.922 +- 0.024) × 10-3
Probability: 0.029 (χ2/dof = 59.8/41)
A plot of the fit result is available in three formats: eps pdf gif
Experiment/Mode | BF [10-4] | Reference |
---|---|---|
CLEO untagged: B^{0} - > \rho^{-} l^{+} \nu | 2.75 +/-0.41 +/- 0.52 | Phys.Rev.D61, 052001 (2000) [hep-ex/9905056] (input) |
CLEO untagged: B^{0} -> \rho^{-} l^{+} \nu | 2.93 +/-0.37 +/- 0.37 | Phys.Rev.Lett.99, 041802 (2007)[arXiv:hep-ex/0703041v2] (input) |
BELLE sl.tag: B^{0} -> \rho^{-} l^{+} \nu | 2.17 +/-0.54 +/-0.32 | Phys.Lett.B648:139-148,2007 [hep-ex/0604024] (input) (param) |
BELLE sl.tag: B^{+} -> \rho^{0} l^{+} \nu | 2.47 +/-0.43 +/-0.33 | Phys.Lett.B648:139-148,2007 [hep-ex/0604024] (input) (param) |
BABAR untagged: B^{0} -> \rho^{-} l^{+} \nu | 1.98 +/-0.21 +/-0.38 | Phys.Rev.D72, 051102 (2011) [arXiv:1005.3288] (input) (param) |
BABAR untagged: B^{+} -> \rho^{0} l^{+} \nu | 1.87 +/-0.19 +/-0.32 | Phys.Rev.D72, 051102 (2011) [arXiv:1005.3288] (input) (param) |
BELLE had.tag: B^{0} -> \rho^{-} l^{+} \nu | 3.22 +/-0.27 +/-0.24 | Phys.Rev.D 88, 032005 (2013)[arXiv:hep-ex/0703041v2] (input)(param) |
BELLE had.tag: B^{+} -> \rho^{0} l^{+} \nu | 3.39 +/-0.18 +/-0.18 | Phys.Rev.D 88, 032005 (2013)[arXiv:hep-ex/0703041v2] (input)(param) |
Average: B ^{0} -> \rho^{-} l^{+} \nu | 2.94 +/- 0.11 +/- 0.17 | Plots: eps pdf gif chi2/dof = 12.8/7 (CL = 0.08) |
Experiment/Mode | BF [10-4] | Parameters | Reference |
---|---|---|---|
BELLE untag | 1.30 +/- 0.40 +/- 0.36 | input parameters | Phys.Rev.Lett 93, 131803 (2004) [arXiv:0402023 [hep-ex]] |
BABAR untag (loose nu-reco) | 1.19 +/- 0.16 +/- 0.09 | input parameters | Phys.Rev.D 86, 092004 (2012) [arXiv:1208.1253 [hep-ex]] |
BABAR untag | 1.21 +/- 0.14 +/- 0.08 | input parameters | Phys.Rev.D87, 032004 (2013) [arXiv:1205.6245 [hep-ex]] |
BELLE had.tag | 1.07 +/- 0.16 +/- 0.07 | input parameters | Phys.Rev.D 88, 032005 (2013) [arXiv:1306.2781 [hep-ex]] |
BABAR sl.tag | 1.35 +/- 0.21 +/- 0.11 | input parameters | Phys.Rev.D88, 072006 (2013) [arXiv:1308.2589 [hep-ex]] |
Average | 1.191+/- 0.084 +/- 0.055 | chi2/dof = 0.02 (CL = 0.91) | eps pdf gif |
Experiment/Mode | BF [10-4] | Parameters | Reference |
---|---|---|---|
BABAR untagged | 0.31+/- 0.06+/- 0.08 | input parameters | Phys.Rev.D79, 052011 (2008) [arXiv:0808.3524 [hep-ex]] |
BABAR sl.Tag | 0.64+/- 0.20+/- 0.03 | input parameters | Phys.Rev.Lett 101, 081801 (2008) [arXiv:0805.2408 [hep-ex]] |
CLEO | 0.44+/- 0.23+/- 0.11 (<1.01 at 90% C.L.) | input parameters | Phys.Rev.D76, 012007 (2007) [arXiv:0703041[hep-ex]] |
BABAR untagged (loose nu-reco) | 0.36+/- 0.05+/- 0.04 | input parameters | Phys.Rev.D83, 052011 (2011) [arXiv:1010.0987 [hep-ex]] |
Average | 0.37 +/- 0.04 +/- 0.04 | chi2/dof = 2.3/3. (CL = 0.51) | eps pdf gif |
Experiment/Mode | BF [10-4] | Parameters | Reference |
---|---|---|---|
CLEO untagged | 2.71+/- 0.80+/- 0.56 | input parameters | Phys.Rev.D76, 012007 (2007) [arXiv:0703042[hep-ex]] |
BABAR sl.tag | 0.04+/- 0.22+/- 0.04 (<0.47 at 90% C.L.) | input parameters | Phys.Rev.Lett 101, 081801 (2008) [arXiv:0808.3524 [hep-ex]] |
BABAR untagged (loose nu-reco) | 0.24 +/- 0.08 +/- 0.03 | input parameters | Phys.Rev.D83, 052011 (2011) [arXiv:1010.0987 [hep-ex]] |
Average | 0.23 +/- 0.08 +/- 0.03 | chi2/dof = 7.2/2. (CL = 0.03) | eps pdf gif |
Last update: Oct 10, 2014