Lepton Mass Effects in Semi-leptonic B-meson Decays
Author: Jürgen G. Körner
Publisher:
Published: 1989
Total Pages: 10
ISBN-13:
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Author: Jürgen G. Körner
Publisher:
Published: 1989
Total Pages: 10
ISBN-13:
DOWNLOAD EBOOKAuthor: Jürgen G. Körner
Publisher:
Published: 1989
Total Pages:
ISBN-13:
DOWNLOAD EBOOKAuthor:
Publisher:
Published: 2007
Total Pages: 359
ISBN-13:
DOWNLOAD EBOOKWe present the results of a search for four exclusive semileptonic decays B → D{sup (*)}[tau]−{bar [nu]}{sub [tau]} in 209 fb−1 of data collected with the BABAR detector, corresponding to 232 million e+e- → [Upsilon](4S) → B{bar B} events. We select events with a D{sup (*)} meson and a light lepton (e or [mu]) recoiling against a fully-reconstructed B meson. We perform a fit to the lepton spectrum and missing mass squared to discriminate signal events from backgrounds, predominantly B → D{sup (*)}{tau}−{bar [nu]}{sub {tau}}. A control sample of identified D**l−{bar {nu}}{sub {ell}} events is included in the fit to estimate the background contribution from these decays. We measure [beta](B → D{sub {tau}{nu}}) = (0.86±0.24±0.11±0.06)% and [beta](B → D*{sub {tau}{nu}}) = (1.62±0.31±0.10±0.05)%, where the errors are statistical, systematic, and normalization-mode related, respectively, and where the results are expressed for the {bar B}° lifetime.
Author: Christopher P. O'Grady
Publisher: Ann Arbor, Mich. : University Microfilms International
Published: 1993
Total Pages: 210
ISBN-13:
DOWNLOAD EBOOKAuthor: Sheldon Stone
Publisher: World Scientific
Published: 1994
Total Pages: 676
ISBN-13: 9789810218362
DOWNLOAD EBOOKThis 2nd edition is an extensive update of "B Decays?. The revisions are necessary because of the extensive amount of new data and new theoretical ideas. This book reviews what is known about b-quark decays and also looks at what can be learned in the future.The importance of this research area is increasing, as evidenced by the approval of the luminosity upgrade for CESR and the asymmetric B factories at SLAC and KEK, and the possibility of experiments at hadron colliders.The key experimental observations made thus far, measurement of the lifetimes of the different B species, B0-B0 mixing, the discovery of ?Penguin? mediated decays, and the extraction of the CKM matrix elements Vub and Vcb from semileptonic decays, as well as more mundane results, are described in great detail by the experimentalists who have been closely involved with making the measurements. Theoretical progress in understanding b-quark decays using HQET and lattice gauge techniques are described by theorists who have developed and used these techniques.Synthesizing the experimental and theoretical information, several articles discuss the implications for the ?Standard Model? and how further tests can be done using measurements of CP violation in the B system.
Author: Michael A. Mazur
Publisher: ProQuest
Published: 2007
Total Pages: 674
ISBN-13: 9780549268611
DOWNLOAD EBOOKWe present the results of a search for four exclusive semileptonic decays B & rarr; D(*)tau -nutau in 209 fb -1 of data collected with the BABAR detector, corresponding to 232 million e+e - & rarr; Upsilon(4S) & rarr; B B events. We select events with a D (*) meson and a light lepton (e or mu) recoiling against a fully-reconstructed B meson. We perform a fit to the lepton spectrum and missing mass squared to discriminate signal events from backgrounds, predominantly B & rarr; D (*) & ell;-nu & ell; . A control sample of identified D** & ell;- nu & ell; events is included in the fit to estimate the background contribution from these decays. We measure B (B & rarr; Dtaunu) = (0.86+/-0.24+/-0.11+/-0.06)% and B (B & rarr; D*taunu) = (1.62+/-0.31+/-0.10+/-0.05)%, where the errors are statistical, systematic, and normalization-mode related, respectively, and where the results are expressed for the B0 lifetime.
Author: Jan Hasenbusch
Publisher:
Published: 2018
Total Pages:
ISBN-13:
DOWNLOAD EBOOKAuthor:
Publisher:
Published: 2011
Total Pages: 159
ISBN-13:
DOWNLOAD EBOOKThis thesis presents first measurements of moments of the hadronic nX2 distribution measured in inclusive semileptonic decays of B mesons to final states containing a charm quark, B 2!Xcl[nu]. The variable nX2 is a combination of the invariant mass of the charmed meson mX, its energy in the B-meson rest-frame EX;BRF, and a constant ~[Lambda] = 0.65 GeV, nX2 = mX2c4-2~[Lambda]EX, BRF + ~[Lambda]2. The moments nXk with k = 2,4,6 are measured as proposed by theory to constrain assumptions made in the theoretical description of inclusive observables in semileptonic B-meson decays. This description uses Heavy Quark Expansion (HQE), an effective QCD combined with an Operator Product Expansion. The measurement is based on a sample of 231.6 million e+e- 2![Upsilon](4S) 2!B$\bar{B}$ events recorded with the BABAR experiment at the PEP-II e+e--storage rings at SLAC. We reconstruct the semileptonic decay by identifying a charged lepton in events tagged by a fully reconstructed hadronic decay of the second B meson. Correction procedures are derived from Monte Carlo simulations to ensure an unbiased measurement of the moments of the nX2 distribution. All moments are measured requiring minimum lepton momenta between 0.8 GeV/c and 1.9 GeV/c in the rest frame of the B meson. Performing a simultaneous fit to the measured moments nXk up to order k = 6 combined with other measurements of moments of the lepton-energy spectrum in decays B 2!Xcl[nu] and moments of the photon-energy spectrum in decays B 2!Xs[gamma], we determine the quark-mixing parameter.
Author: Frank Juergen Tackmann
Publisher:
Published: 2008
Total Pages: 290
ISBN-13:
DOWNLOAD EBOOKAuthor: Jan Hasenbusch
Publisher:
Published: 2018
Total Pages:
ISBN-13:
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