Download or read book Determination of the Branching Fraction for B Rightarrow X sub C Ell Nu Decays and of verticalV sub Cb vertical from Hadronic Mass and Lepton Energy Moments written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We determine the inclusive B [yields] X[sub c][ell][nu] branching fraction, [Beta][sub c[ell][nu]], the CKM matrix element V[sub cb], and other heavy-quark parameters from a simultaneous fit to moments of the hadronic-mass and lepton-energy distributions in semileptonic B-meson decays, measured as a function of the lower limit on the lepton energy, using data recorded with the BABAR detector. Using Heavy Quark Expansions (HQEs) to order 1/m[sub b][sup 3], we extract [Beta][sub ce[nu]] = (10.61 [+-] 0.16[sub exp] [+-] 0.06[sub HQE])% and V[sub cb] = (41.4 [+-] 0.4[sub exp] [+-] 0.4[sub HQE] [+-] 0.6[sub th]) x 10[sup -3]. The stated errors refer to the experimental, HQE, and additional theoretical uncertainties.

Download or read book Determination of the Branching Fraction for B Rightarrow X sub C Ell Nu Decays and of written by and published by . This book was released on 2004 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: We determine the inclusive B → X{sub c}l[nu] branching fraction, [Beta]{sub c{ell}[nu]}, the CKM matrix element.

Download or read book Determination of verticalV sub Cb vertical and Results from BABAR written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The CKM matrix element amplitude V[sub cb] was determined using the data collected by the BABAR detector. The partial branching fraction, lepton-energy moments, and hadron-mass moments were measured in inclusive semileptonic decays B [yields] X[sub c][ell][nu]. A global fit to a Heavy-Quark-Expansion calculation allowed precise determination of V[sub cb], m[sub b], m[sub c], [Beta](B [yields] X[sub c][ell][nu]) and four non-perturbative parameters.

Download or read book Inclusive Semileptonic B Decays at BABAR and Extraction of HQE Parameters written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of the first four moments of the hadronic mass distribution in B [yields] C[sub c][ell][bar [nu]] decays is presented for minimum lepton momenta varying between 0.9 and 1.6 GeV, using data recorded with the BABAR detector. Furthermore, a measurement of the inclusive electron energy spectrum for semileptonic B decays together with a measurement of its first, second and third moments for minimum electron energies between 0.6 and 1.5 GeV is reported. We determine the inclusive B [yields] X[sub c][ell][bar [nu]] branching fraction, [Beta][sub c[ell][nu]], the CKM matrix element V[sub cb], and other heavy-quark parameters from a simultaneous fit to the measured moments.

Download or read book Measurement of the First and Second Moments of the Hadronic Mass Distribution in Semileptonic B Decays written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report a preliminary measurement of the first and second moments of the hadronic mass distributions in B[yields] X[sub c][ell][nu] decays. The measurements are based on[Upsilon](4S)[yields] B[bar B] events where the hadronic decay of one of the B mesons is fully reconstructed and a charged lepton from the decay of the other B meson is identified. The moments are presented for threshold lepton momenta ranging from 0.9 to 1.6 GeV. From theM[sub X][sup 2] moments we determine the non-perturbative Heavy Quark Expansion (HQE) parameters, [bar[Lambda]] and[lambda][sub 1]. We combine the measured momentsM[sub X][sup 2] with earlier BABAR measurements of the semileptonic branching ratios and B lifetimes and perform a simultaneous fit to the HQE for the moments obtained for different threshold lepton momenta and the semileptonic decay width. This fit results in an improved value for the CKM matrix elementV[sub cb].

Download or read book Studies of Inclusive Semileptonic B Meson Decays with the BABAR Detector written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a brief report on the measurement of the inclusive branching fraction[Beta]([bar B][yields] X[sub c][ell][sup -][bar[nu]]) and the preliminary measurement of the first moment of the hadron mass M[sub X] in such decays. The implications of these results onV[sub cb] are discussed.

Download or read book Measurement Of verticalV sub Cb vertical Using bar B sup 0 yields D sup ell sup bar nu sub ell Decays written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A preliminary measurement ofV[sub cb] and the branching fraction[Beta]([bar B][sup 0][yields] D*[sup+][ell][sup -][bar[nu]][sub[ell]]) has been performed based on a sample of about 55,700[bar B][sup 0][yields] D*[sup+][ell][sup -][bar[nu]][sub[ell]] decays recorded with the BABAR detector. The decays are identified in the D*[sup+][yields] D[sup 0][pi][sup+] final state, with the D[sup 0] reconstructed in three different decay modes. The differential decay rate is measured as a function of the relativistic boost of the D*[sup+] in the[bar B][sup 0] rest frame. The value of the differential decay rate at ''zero recoil'', namely the point at which the D*[sup+] is at rest in the[bar B][sup 0] frame, is predicted in Heavy Quark Effective Theory as a kinematic factor times F(1)V[sub cb], where F is the unique form factor governing the decay. We extrapolate the measured differential decay rate to the zero recoil point and obtain F(1)V[sub cb]= (34.03[+-] 0.24[+-] 1.31) x 10[sup -3]. Using a theoretical calculation for F(1) we extractV[sub cb]= (37.27[+-] 0.26(stat.)[+-] 1.43(syst.)[sub -1.2][sup+1.5](theo.)) x 10[sup -3]. From the integrated decay rate we obtain[Beta]([bar B][sup 0][yields] D*[sup+][ell][sup -][bar[nu]][sub[ell]])= (4.68[+-] 0.03[+-] 0.29)%.

Download or read book Measurements of Moments of the Hadronic Mass Distribution in Semileptonic B Decays written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report a measurement of the first four moments of the hadronic mass distribution in [bar B] [yields] X[sub c][ell][sup -] [bar [nu]] decays. The measurements are based on 89 million [Upsilon](4S) [yields] B[bar B] events where the hadronic decay of one of the B mesons is fully reconstructed and a charged lepton from the decay of the other B meson is identified. The moments are presented for minimum lepton momenta ranging from 0.9 to 1.6 GeV in the B rest frame. It is expected that such measurements will lead to improved determinations of V[sub cb] and V[sub ub].

Download or read book Measurement of the Hadronic Mass Spectrum in B right Arrow X subscript U l nu Decays and Determination of the B quark Mass at the BABAR Experiment written by Kerstin Tackmann and published by . This book was released on 2008 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Branching Fraction Measurements of B Eta C K Decays written by and published by . This book was released on 2004 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: We study the decays B 2![eta]{sub c}K and B° 2![eta]{sub c}K°, where the [eta]{sub c} is reconstructed in the K{sub S}° K{sup ±} [pi]{sup {-+}} and K+K− [pi]° decay modes. Results are based on a sample of 86 million B{bar B} pairs collected with the BABAR detector at the SLAC e+e− B Factory. We measure the branching fractions [Beta](B+ 2![eta]{sub c}K+) = (1.34 ± 0.09 ± 0.13 ± 0.41) x 10−3 and [Beta](B° 2![eta]{sub c}K°) = (1.18 ± 0.16 ± 0.13 ± 0.37) x 10−3, where the first error is statistical, the second is systematic, and the third reflects the [eta]{sub c} branching fraction uncertainty. In addition, we search for B 2![eta]{sub c}K events with [eta]{sub c} 2!2(K+K−) and [eta]{sub c} 2![phi][phi] and determine the [eta]{sub c} decay branching fraction ratios [Beta]([eta]{sub c} 2!2(K+K−))/[Beta]([eta]{sub c} 2!K{bar K}[pi]) = (2.3 ± 0.7 ± 0.6) x 10−2 and [Beta]([eta]{sub c} 2![phi][phi])/[Beta]([eta]{sub c} 2!K{bar K}[pi]) = (5.5 ± 1.4 {+-} 0.5) x 10−2.

Download or read book Branching Fraction for B Pi0 L Nu Measured in Upsilon 4S BBbar Events Tagged by B D0 L Nubar X Decays written by J. C. Chen and published by . This book was released on 2005 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report a preliminary branching fraction of (1.80 {+-} 0.37{sub stat.} {+-} 0.23{sub syst.}) x 10{sup -4} for the charmless exclusive semileptonic B{sup +} {yields} {pi}{sup 0}{ell}{sup +}{nu} decay, where {ell} can be either a muon or an electron. This result is based on data corresponding to an integrated luminosity of 81 fb{sup -1} collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses B{bar B} events that are tagged by a B meson reconstructed in the semileptonic B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}(X) decays, where X can be either a {gamma} or a {pi}{sup 0} from a D* decay.

Download or read book Measurement of the Partial Branching Fraction for Inclusive Charmless Semileptonic B Decays and Extraction of written by and published by . This book was released on 2005 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Charmless semileptonic decays, {bar B} 2!X{sub u}l{bar {nu}}, are studied in a sample of 232 million B{bar B} decays recorded with the BABAR detector, in events where the decay of the second B meson is fully reconstructed. Inclusive charmless decays are selected in kinematic regions where the dominant background from semileptonic B decays to charm is reduced by requirements on the hadronic mass M{sub X} and the momentum transfer q2. The partial branching fraction for {bar B} 2!X{sub u}l{bar {nu}} decays for M{sub X} 1.7 GeV/c2 and q2 8 GeV2/c4 is measured to be [Delta][Beta]({bar b} 2!X{sub u}l{bar {nu}}) = (0.87 ± 0.09{sub stat} ± 0.09{sub sys} ± 0.01{sub th}) x 10−3. The CKM matrix element.

Download or read book Measurement of the Relative Branching Fractions for B to D D D D pi ell bar nu ell with a Large Sample of Tagged B Mesons written by B. Aubert and published by . This book was released on 2006 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a study of B semileptonic decays into charm final states based on 211.7 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. Using a novel technique based on the simultaneous fit of a set of variables reconstructed on the recoil of a B tagged in an hadronic decay mode, we measure the relative branching fractions {Lambda}(B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}{sub {ell}}) = 0.611 {+-} 0.022 (stat.) {+-} 0.027 (syst.) and {Lambda}(B{sup -} {yields} D**{sup 0})(D{sup (*)}{pi}){ell}{sup -}{bar {nu}}{sub {ell}}/{Lambda}(B{sup -} {yields} DX{ell}{sup -}{bar {nu}}{sub {ell}}) = 0.173 {+-} 0.017 (stat.) {+-} 0.021 (syst.).

Download or read book Measurement of the Branching Fractions of Bbar D L Nubar l Decays in Events Tagged by a Fully Reconstructed B Meson written by and published by . This book was released on 2008 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report a measurement of the branching fractions of {bar B} 2!D** l−{bar {nu}}{sub l} decays based on 417 fb−1 of data collected at the [Upsilon](4S) resonance with the BABAR detector at the PEP-II ee− storage rings. Events are selected by fully reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D{sup (*)})-m(D{sup (*)}) is performed to extract the signal yields of the different D** states. We observe the {bar B} 2!D**{ell}−{bar {nu}}{sub {ell}} decay modes corresponding to the four D** states predicted by Heavy Quark Symmetry with a significance greater than six standard deviations including systematic uncertainties.

Download or read book Branching Fraction for B0 Pi L Nu and Determination of written by and published by . This book was released on 2005 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report preliminary results from a study of the charmless exclusive semileptonic decay B° →?−l? based on the data collected at the?(4S) resonance using the BABAR detector at SLAC. The analysis uses events in which the signal B meson recoils against a B meson that has been reconstructed in a semileptonic decay {bar B}° → D{sup (*)+}l−{bar?}. We extract the total branching fraction?(B° →?−l+{nu}) = (1.03 ± 0.25{sub stat.} ± 0.13{sub syst.}) x 10−4 and the partial branching fractions in three bins of q2, the invariant mass squared of the lepton-neutrino system. From the partial branching fractions and theoretical predictions for the form factors, we determine the magnitude of the CKM matrix element.

Download or read book Inclusive Semileptonic B Decays at BABAR written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report updates on two analyses of inclusive semileptonic B decays based on a dataset of 89 million B[bar B] events recorded with the BABAR detector at the [Upsilon](4S) resonance. Events are selected by fully reconstructing the decay of one B meson and identifying a charged lepton from the decay of the other [bar B] meson. IN the first analysis, the measurement of the first and second moment of the hadronic mass distribution in Cabibbo-favored [bar B] [yields] X[sub c][ell][bar [nu]] decays allows for the determination of the nonperturbative parameters [bar [Lambda]] and [lambda][sub 1] of Heavy Quark Effective Theory (HQET) and V[sub cb]. In the second analysis, the hadronic mass distribution is used to measure the inclusive charmless semileptonic branching fraction and to determine V[sub ub].

Download or read book Recueil factice d articles de presse concernant Henriette Berthias written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: