Measurement of the Q2 Dependence of the Hadronic Form Factor in D0 to K- E+ Nu_e Decays

Measurement of the Q2 Dependence of the Hadronic Form Factor in D0 to K- E+ Nu_e Decays PDF Author: B. Aubert
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ISBN:
Category :
Languages : en
Pages : 23

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A preliminary measurement of the q{sup 2} dependence of the D{sup 0} {yields} K{sup -}e{sup +}{nu}{sub e} decay rate is presented. This rate is proportional to the hadronic form factor squared, specified by a single parameter. This is either the mass in the simple pole ansatz m{sub pole} = (1.854 {+-} 0.016 {+-} 0.020) GeV/c{sup 2} or the scale in the modified pole ansatz {alpha}{sub pole} = 0.43 {+-} 0.03 {+-} 0.04. The first error refers to the statistical, the second to the systematic uncertainty.

Measurement of the Q2 Dependence of the Hadronic Form Factor in D0 to K- E+ Nu_e Decays

Measurement of the Q2 Dependence of the Hadronic Form Factor in D0 to K- E+ Nu_e Decays PDF Author: B. Aubert
Publisher:
ISBN:
Category :
Languages : en
Pages : 23

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Book Description
A preliminary measurement of the q{sup 2} dependence of the D{sup 0} {yields} K{sup -}e{sup +}{nu}{sub e} decay rate is presented. This rate is proportional to the hadronic form factor squared, specified by a single parameter. This is either the mass in the simple pole ansatz m{sub pole} = (1.854 {+-} 0.016 {+-} 0.020) GeV/c{sup 2} or the scale in the modified pole ansatz {alpha}{sub pole} = 0.43 {+-} 0.03 {+-} 0.04. The first error refers to the statistical, the second to the systematic uncertainty.

Measurement of the Hadronic Form Factor in D0 to K- E+ Nu_e Decays

Measurement of the Hadronic Form Factor in D0 to K- E+ Nu_e Decays PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 21

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The shape of the hadronic form factor f+ (q2) in the decay D° → K− e?{sub e} has been measured in a model independent analysis and compared with theoretical calculations. They use 75 fb−1 of data recorded by the BABAR detector at the PEPII electron-positron collider. The corresponding decay branching fraction, relative to the decay D° → K−?+, has also been measured to be R{sub D} = BR(D° → K−e+?{sub e})/BR(D° → K−?+) = 0.927 ± 0.007 ± 0.012. From these results, and using the present world average value for BR(D° → K−?+), the normalization of the form factor at q2 = 0 is determined to be f+(0) = 0.727 ± 0.007 ± 0.005 ± 0.007 where the uncertainties are statistical, systematic, and from external inputs, respectively.

Measurement of the Hadronic Form Factors in Ds to Phi E Nu Decays

Measurement of the Hadronic Form Factors in Ds to Phi E Nu Decays PDF Author: J. Serrano
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ISBN:
Category :
Languages : en
Pages : 21

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Based on the measured four-dimensional rate for D{sub s}{sup +} {yields} {phi}e{sup +}{nu}{sub e} decays, they have determined the ratios of the three hadronic form factors, {tau}{sub V} = V(0)/A{sub 1}(0) = 1.636 {+-} 0.067 {+-} 0.038 and {tau}{sub 2} = A{sub 2}(0)/A{sub 1}(0) = 0.705 {+-} 0.056 {+-} 0.029, using a simple pole ansatz for the q{sup 2} dependence, with fixed values of the pole masses for both the vector and axial form factors. By a separate fit to the same data, they have also extracted the pole mass for the axial form factors, m{sub A}: {tau}{sub V} = V(0)/A{sub 1}(0) = 1.633 {+-} 0.081 {+-} 0.068, {tau}{sub 2} = A{sub 2}(0)/A{sub 1}(0) = 0.711 {+-} 0.111 {+-} 0.096 and m{sub A} = (2.53{sub -0.35}{sup +0.54} {+-} 0.54)GeV/c{sup 2}.

Nuclear Science Abstracts

Nuclear Science Abstracts PDF Author:
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ISBN:
Category : Nuclear energy
Languages : en
Pages : 964

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Energy Research Abstracts

Energy Research Abstracts PDF Author:
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ISBN:
Category : Power resources
Languages : en
Pages : 1010

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Physics Briefs

Physics Briefs PDF Author:
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ISBN:
Category : Physics
Languages : en
Pages : 910

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Reconstruction of B- --] D*° E- Nu Decays and Determination of |Vcb|

Reconstruction of B- --] D*° E- Nu Decays and Determination of |Vcb| PDF Author:
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ISBN:
Category :
Languages : en
Pages :

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In this analysis the decay B- --> D*° e- nu is measured. The underlying data sample consists of about 226 million B-meson pairs accumulated on the Y(4S) resonance by the BABAR detector at the asymmetric e+e- collider PEP II. The reconstruction of the decay uses the channels D*° --> D° pi°, D° --> K- pi+ and pi° --> gamma gamma. The neutrino is not reconstructed. Since the rest frame of the B meson is unknown, the boost w of the D*° meson in the B meson rest frame is estimated by w'. The w' spectrum of the data is described in terms of the partial decay width dGamma/dw given by theory and the detector simulation translating each spectrum dGamma/dw into an expectation of the measured w' spectrum. dGamma/dw depends on a form factor F(w) parameterizing the strong interaction in the decay process. To find the best descriptive dGamma/dw a fit to the data determines the following two parameters of dGamma/dw: (i) F(1)|Vcb|, the product between F at zero D*°-recoil and the Quark mixing parameter |Vcb|; (ii) rho^2, a parameter of the form factor F(w). The former parameter scales the height of dGamma/dw and rho^2 varies the shape of it. The determined values of F(1)|Vcb|, rho^2 and the branching fraction BF(B- --> D*° e- nu) are F(1)|Vcb| = (35.8 +- 0.5 +- 1.5) x 10e-03, rho^2 = (1.08 +- 0.05 +- 0.09) and BF(B- --> D*° e- nu) = (5.60 +- 0.08 +- 0.42)%, where the uncertainties are statistical and systematic, respectively. The value of BF(B- --> D*° e- nu) has been determined by an integration of dGamma/dw over the allowed w range using the fitted values of F(1)|Vcb| and rho^2.

INIS Atomindeks

INIS Atomindeks PDF Author:
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ISBN:
Category : Nuclear energy
Languages : en
Pages : 1116

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Study of the Ds+ to K+K-e+ Nu Decay Channel with the BaBar Experiment

Study of the Ds+ to K+K-e+ Nu Decay Channel with the BaBar Experiment PDF Author:
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ISBN:
Category :
Languages : en
Pages : 236

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Charm semileptonic decays allow a validation of lattice QCD calculations through the measurement of the hadronic form factors, which characterize the effect of strong interaction in these reactions. The accuracy of such calculations is crucial for the improvement of the test of the standard model in flavor physics. This thesis presents a study of the Ds+ → K+K-e+ve channel using 214 fb-1 recorded by de BAbar experiment. For events with a K+K- mass in the range between 1.01 GeV/c2 and 1.03 Gev/c2, the [Phi] → K+K- is the dominant component. Using the simple pole model to parameterize the q2 dependence of the form factors -V(q2), A1(q2) and A2(q2)- the following ratios are measured at q2 = 0; [tau]V = V(0)/A1(0) = 1.868 ± 0.061 ± 0.079, r2 = A2(0)/A1(0) = 0.763 ± 0.072 ± 0.062. The mass pole of the axial-vector form factor is also obtained: mA = (2.30-0.18+0.42 ± 0.21) GeV/c2. In the same mass range, the semileptonic branching fraction, relative to the Ds+ → [Phi][pi]+ channel, is measured, and the absolute normalization of the axial-vector form factor is extracted: A1(q2 = 0) and = 0.605 ± 0.012 ± 0.018 ± 0.018. The stated errors refer to the statistical, systematic and errors from external inputs, respectively. An S wave component in the K+K- system, possibly originating from a f0, is also studied through its interference with the [Phi]. An S wave component is observed for the first time in this decay channel with a 5[sigma] significance.

Measurement of *Ga*Us in Hadronic Z Decays Using All-orders Resummed Predic

Measurement of *Ga*Us in Hadronic Z Decays Using All-orders Resummed Predic PDF Author: Et al
Publisher:
ISBN:
Category :
Languages : en
Pages : 14

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