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Related papers: |V_ub| from UTangles and B->pi l nu

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We discuss the present status of global fits to the CKM unitary triangle using the latest experimental and theoretical constraints. For the required nonperturbative weak matrix elements, we use three-flavor lattice QCD averages from…

High Energy Physics - Phenomenology · Physics 2012-04-25 Jack Laiho , Enrico Lunghi , Ruth S. Van de Water

We calculate the electron spectrum of semileptonic decays of B-mesons into non-charmed hadrons. The shape of the spectrum obtained from QCD sum rules is in general agreement with quark model calculations. At high electron energies the…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. Ball , V. M. Braun , H. G. Dosch

We present an analysis of exclusive charmless semileptonic B-meson decays based on 377 million BBbar pairs recorded with the BABAR detector at the Upsilon(4S) resonance. We select four event samples corresponding to the decay modes B0 -->…

High Energy Physics - Experiment · Physics 2011-02-18 The BABAR Collaboration , P. del Amo Sanchez

In this work, I suggest a new way for determining the CKM angle $\gamma$ via B decays into a scalar/tensor meson without any hadronic uncertainty. The proposed idea makes profits of the two triangles formed by the $B^\pm\to (D^0,\bar…

High Energy Physics - Phenomenology · Physics 2015-06-11 Wei Wang

A bound on the angle gamma of the unitarity triangle is derived using experimental information on the CP-averaged branching ratios for the rare decays B^+- -> pi^+- K^0 and B^+- -> pi^0 K^+-. The theoretical description is cleaner than the…

High Energy Physics - Phenomenology · Physics 2010-11-23 M. Neubert , J. L. Rosner

We present an analysis of exclusive charmless semileptonic B-meson decays based on 83 million BBbar pairs recorded with the BABAR detector at the Upsilon(4S) resonance. Using isospin symmetry, we measure branching fractions B(B0 --> pi- l+…

High Energy Physics - Experiment · Physics 2010-03-19 The BABAR Collaboration , B. Aubert

We make the simple observation that there exists a universal unitarity triangle for all models, like the SM, the Two Higgs Doublet Models I and II and the MSSM with minimal flavour violation, that do not have any new operators beyond those…

High Energy Physics - Phenomenology · Physics 2010-11-23 A. J. Buras , P. Gambino , M. Gorbahn , S. Jager , L. Silvestrini

We address the problem of extrapolating the vector form factor $f_{B\pi}^+$, which is relevant to $B\to \pi\ell \nu_\ell$ decays, from the region of small to the region of large momentum transfer. As input, we use the QCD light-cone sum…

High Energy Physics - Phenomenology · Physics 2015-03-06 I. Sentitemsu Imsong , Alexander Khodjamirian , Thomas Mannel , Danny van Dyk

We present results of a lattice study of the form factors in the decay B-> pi l nu. We attempt to disentangle the the dependence of the form factors on the light quark masses and the momentum transfer. Using models of the q^2 dependence we…

High Energy Physics - Lattice · Physics 2007-05-23 UKQCD Collaboration , C. M. Maynard

Using BaBar measurements of the inclusive electron spectrum in B->X_u e nu decays and the inclusive photon spectrum in B->X_s gamma decays, we extract the magnitude of the CKM matrix element Vub. The extraction is based on theoretical…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. B. Golubev , V. G. Luth , Yu. I. Skovpen

I review currently discussed methods to determine the CKM mixing matrix element $|V_{ub}|$ from experimental data. Although the theory of inclusive decays and their spectra has entered a model-independent stage, its predictions are still…

High Energy Physics - Phenomenology · Physics 2007-05-23 Patricia Ball

The angle gamma of the standard CKM unitarity triangle can be determined from B -> D K decays with a very small irreducible theoretical error, which is only due to second-order electroweak corrections. We study these contributions and…

High Energy Physics - Phenomenology · Physics 2015-06-17 Joachim Brod , Jure Zupan

The persistent tensions between inclusive and exclusive determinations of $|V_{cb}|$ and $|V_{ub}|$ weaken the power of theoretically clean rare $K$ and $B$ decays in the search for new physics (NP). We demonstrate how this uncertainty can…

High Energy Physics - Phenomenology · Physics 2022-03-22 Andrzej J. Buras , Elena Venturini

The unitarity triangle can be determined by means of two measurements of its sides or angles. Assuming the same relative errors on the angles $(\alpha,\beta,\gamma)$ and the sides $(R_b,R_t)$, we find that the pairs $(\gamma,\beta)$ and…

High Energy Physics - Phenomenology · Physics 2010-11-23 Andrzej J. Buras , Fabrizio Parodi , Achille Stocchi

Constraints on the CKM angle \gamma are presented from GLW, ADS, and GGSZ analyses of B+- -> D K+- at the LHCb experiment. The branching fractions of B0 -> D0bar K+ \pi- and Bs -> D0bar K- \pi+ are also reported, measured relative to the…

High Energy Physics - Experiment · Physics 2013-10-01 Daniel Craik

We present constraints on the CKM parameter gamma=arg(Vub*) formed within the framework of SU(3) symmetry and based on charmless hadronic B decays to K*+- pi-+ and other pseudoscalar-vector final states. For strong phases of O(10 degrees),…

High Energy Physics - Phenomenology · Physics 2007-05-23 Werner M. Sun

The system of $B^0_s\to D_s^\mp K^\pm$ decays offers a theoretically clean determination of the angle $\gamma$ of the Unitarity Triangle. A corresponding LHCb analysis resulted in a surprisingly large result, which is in tension with other…

High Energy Physics - Phenomenology · Physics 2022-09-21 Robert Fleischer , Eleftheria Malami

We investigate the sensitivity with which two angles of the "flat" unitarity triangle, defined by $V_{ub}^* V_{us} + V_{cb}^* V_{cs} + V_{tb}^* V_{ts} =0$, can possibly be measured directly at FCCee. We show that the measured errors on the…

High Energy Physics - Phenomenology · Physics 2022-04-06 Roy Aleksan , L. Oliver , Emmanuel Perez

We point out that the recently increased value of the angle $\gamma$ in the Unitarity Triangle (UT), determined in tree-level decays to be $\gamma=(74.0^{+5.0}_{-5.8})^\circ$ by the LHCb collaboration, combined with the most recent value of…

High Energy Physics - Phenomenology · Physics 2019-02-27 Monika Blanke , Andrzej J. Buras

Semileptonic ${B}$ meson decays involving low-mass charged leptons ${e}$ or ${\mu}$ are expected to be free of non-Standard Model contributions and therefore play a critical role in determinations of ${\vert V_{ub} \vert}$ and ${\vert…

High Energy Physics - Experiment · Physics 2019-08-13 Matic Lubej