This fit was prepared for the PDG09 web update and uses only published measurements. For a fit including preliminary numbers refer to here. We use all moment measurements of the hadronic mass and lepton energy distributions in B -> Xclnu and of the photon energy distribution in B -> Xsgamma decays where correlation matrices are available. The fit follows closely the approach of Phys.Rev. D78 (2008) 032016.
Theoretical inputs are the calculations in Eur.Phys.J. C34 (2004) 181-189 and Nucl.Phys. B710 (2005) 371-401. Errors concerning the accuracy in the expression for a given moment have been assigned following the recipes given by the authors of the above publications. The calculation of |Vcb| uses the expression from Nucl.Phys. B665 (2003) 367-401.
Input | |V_{cb}| (10^{-3}) | m_{b}^{kin} (GeV) | mu^{2}_{pi} (GeV^{2}) | chi^{2}/ndf. | |
---|---|---|---|---|---|
all moments (Xclnu and Xsgamma) | 41.54 +/- 0.43(fit) +/- 0.08(tau_{B}) +/- 0.58(th) | 4.620 +/- 0.035 | 0.424 +/- 0.042 | details | 26.4 / (64-7) |
Xclnu only | 41.31 +/- 0.49(fit) +/- 0.08(tau_{B}) +/- 0.58(th) | 4.678 +/- 0.051 | 0.410 +/- 0.046 | details | 20.3 / (53-7) |
Figures of the Delta chi^{2}=1 ellipses can be found here:
We consider two data samples for the fit (Table 1), using:
Experiment | Hadron moments <M^{n}_{X}> | Lepton moments <E^{n}_{l}> | Photon moments <E^{n}_{gamma}> | References |
---|---|---|---|---|
BaBar | n=2 c=0.9,1.1,1.3,1.5 n=4 c=0.9,1.0,1.2,1.4 [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 [2] |
n=1 c=1.9,2.0 n=2 c=1.9 [3,4] |
[1] Phys.Rev. D69
(2004) 111103 [2] Phys.Rev. D69 (2004) 111104 [3] Phys.Rev. D72 (2005) 052004 [4] Phys. Rev. Lett. 97, 171803 (2006) |
Belle | n=2 c=0.7,1.1,1.3,1.5 n=4 c=0.7,0.9,1.3 [5] |
n=0 c=0.6,1.0,1.4 n=1 c=0.6,0.8,1.0,1.2,1.4 n=2 c=0.6,1.0,1.4 n=3 c=0.8,1.0, 1.2 [6] |
n=1 c=1.8,1.9 n=2 c=1.8,2.0 [7] |
[5]
Phys.Rev. D75 (2007) 032005 [6] Phys.Rev. D75 (2007) 032001 [7] Phys.Rev. D78 (2008) 032016 |
CDF | n=2 c=0.7 n=4 c=0.7 [8] |
. | . | [8] Phys.Rev. D71 (2005) 051103 |
CLEO | n=2 c=1.0,1.5 n=4 c=1.0,1.5 [9] |
. | n=1 c=2.0 [10] | [9]
Phys.Rev. D70 (2004) 032002 [10] Phys.Rev.Lett. 87 (2001) 251807 |
DELPHI | n=2 c=0.0 n=4 c=0.0 [11] |
n=1 c=0.0 n=2 c=0.0 n=3 c=0.0 [11] |
. | [11] Eur.Phys.J. C45 (2006) 35-59 |
last update: Apr 17, 2009 by C.Schwanda