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Related papers: A new sum rule to determine Vub/Vcb

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We summarize the recent strategy for an efficient hunting of new animalcula with the help of rare K and B decays that avoids the use of the $V_{cb}$ and $V_{ub}$ parameters that are subject to tensions between their determinations from…

High Energy Physics - Phenomenology · Physics 2025-01-08 Andrzej J. Buras

We report on recent improvements for the $B\to\pi$ form factor. The updated value of $|V_{ub}|$ is presented.

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Weinzierl , O. Yakovlev

We use QCD sum rules to study the masses of the baryons $\Xi_c$ and $\Xi_b$. We work with a current where the strange and the light quarks are in a relative spin zero, at leading order in $\alpha_s$. We consider the contributions of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Francisco O. Durães , Marina Nielsen

We derive a model-independent upper bound for the axial-vector form factor of the $B\ra D^*$ transition at zero recoil, $F_{B\ra D^*}$. The form factor turns out to be noticeably less than unity. The deviation of $F_{B\ra D^*}$ from unity…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Shifman , N. G. Uraltsev , A. Vainshtein

Applications of QCD sum rules to exclusive decays of heavy mesons are reviewed. In detail, we discuss the calculations of the B and $D$ decay constants, the heavy-to-light form factors $f^+(p^2)$ and $f^0(p^2)$, and the strong couplings…

High Energy Physics - Phenomenology · Physics 2016-11-03 A. Khodjamirian , R. Rückl

Recent progress in flavor physics is discussed. In particular, I review theoretical and experimental developments relevant for semileptonic B decays and the determination of |Vcb| and |Vub|, for exclusive rare decays, for nonleptonic b->c…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zoltan Ligeti

We report on determinations of |Vub| resulting from studies of the branching fraction and q^2 distributions in exclusive semileptonic B decays that proceed via the b->u transition. Our data set consists of the 9.7x10^6 BBbar meson pairs…

High Energy Physics - Experiment · Physics 2010-04-08 S. B. Athar

Unitarity along with precision measurements of sin2\beta, V_{us} and V_{cb} allows one to find a lower bound V_{ub}\geq 0.0035 which, on using the recently measured angle \alpha of the unitarity triangle, translates to V_{ub}= 0.0035\pm…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gulsheen Ahuja , Manmohan Gupta , Sanjeev Kumar , Monika Randhawa

The difference of vector and axial-vector charged current correlators is analyzed by means of QCD sum rules. The contribution of 10-dimensional 4-quark condensates is calculated and its value is estimated within the framework of…

High Energy Physics - Phenomenology · Physics 2009-11-10 K. N. Zyablyuk

I discuss the theoretical uncertainties in the extraction of $|\,V_{cb}|$ from semilep\-to\-nic decays of $B$ mesons, taking into account the most recent theoretical developments. The main sources of uncertainty are identified both for the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthias Neubert

We review QCD sum rule applications to hadronic matrix elements of exclusive $B$ and $D$ decays. Results are presented for the form factors $f^+$ and $F_0$ of $B \rightarrow \pi$ and $D\rightarrow \pi$ transitions. The predictions are used…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Khodjamirian , R. Rückl

The present status of the measurement of the semileptonic B decays is reviewed. Emphasis is given on the factors affecting experimental errors of the Cabibbo-Kobayashi-Masawa matrix element |Vcb | and |Vub |.

High Energy Physics - Experiment · Physics 2007-05-23 Elisabetta Barberio

We present updated results for $\varepsilon_K$ determined directly from the standard model (SM) with lattice QCD inputs such as $\hat{B}_K$, $|V_{cb}|$, $|V_{us}|$, $\xi_0$, $\xi_2$, $\xi_\text{LD}$, $f_K$, and $m_c$. We find that the…

High Energy Physics - Lattice · Physics 2019-12-13 Jeehun Kim , Sunkyu Lee , Weonjong Lee , Yong-Chull Jang , Jaehoon Leem , Sungwoo Park

We study semi-inclusive charmless decays $B \to \pi X$, where $X$ does not contain a charm (anti)quark. The mode $\bar B^0 \to \pi^- X$ turns out to be be particularly useful for determination of the CKM matrix element $|V_{ub}|$. We…

High Energy Physics - Phenomenology · Physics 2009-11-07 C. S. Kim , Jake Lee , Sechul Oh

The ratio between the photon spectrum in B -> X_s gamma and the differential semileptonic rate wrt the hadronic variable M_X/E_X is a short-distance quantity calculable in perturbation theory and independent of the Fermi motion of the b…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ugo Aglietti , Marco Ciuchini , Paolo Gambino

I present an overview of the experimental situation for the determination of |Vub| from semileptonic B-meson decays.

High Energy Physics - Experiment · Physics 2011-10-11 Florian U. Bernlochner

We present a measurement of the branching fraction for the semileptonic B decay Bbar -> D+l-nubar, where l- can be either an electron or a muon. We find Gamma(Bbar -> D+l-nubar)= (13.79+/-0.76+/-2.51) ns^{-1}, and the resulting branching…

High Energy Physics - Experiment · Physics 2008-11-26 Belle Collaboration , K. Abe

An elementary approach is shown which derives the value of the Gauss sum of a cubic character over a finite field $\mathbb F_{2^s}$ without using Davenport-Hasse's theorem (namely, if $s$ is odd the Gauss sum is -1, and if $s$ is even its…

Number Theory · Mathematics 2011-05-03 Davide Schipani , Michele Elia

In this addendum to "$B_s$ mixing observables and $|V_{td}/V_{ts}|$ from sum rules" \cite{King:2019lal} we study the impact of the recent improvements in the theoretical precision of $B$ meson mixing onto CKM unitarity fits. Our key results…

High Energy Physics - Phenomenology · Physics 2020-03-20 Daniel King , Matthew Kirk , Alexander Lenz , Thomas Rauh

In the leading order of the heavy quark expansion, we propose a method within the OPE and the trace formalism, that allows to obtain, in a systematic way, Bjorken-like sum rules for the derivatives of the elastic Isgur-Wise function…

High Energy Physics - Phenomenology · Physics 2011-01-25 A. Le Yaouanc , L. Oliver , J. -C. Raynal