中文
相关论文

相关论文: Explaining B \to K pi anomaly with non-universal Z…

200 篇论文

The role of penguin amplitudes in CP violating $B$ decays is reviewed, emphasizing recent progress in the analysis of electroweak penguin contributions. It is shown how these terms are included in a model-independent manner when measuring…

高能物理 - 唯象学 · 物理学 2007-05-23 Michael Gronau

B-meson decays play an important role in flavour physics. The $B \rightarrow \pi K$ decays are dominated by QCD loop diagrams (penguins) but also electroweak penguins, where New Physics may enter, have a significant impact on the decay…

高能物理 - 唯象学 · 物理学 2020-08-25 Eleftheria Malami

In left-right models the gluonic penguin contribution to b --> s s-bar s transition is enhanced by m_t/m_b due to the presence of (V+A) currents and by the larger values of loop functions than in the Standard Model. Together those may…

高能物理 - 唯象学 · 物理学 2009-11-07 Martti Raidal

I discuss some puzzles observed in exclusive $B$ meson decays, concentrating on the large difference between the direct CP asymmetries in the $B^0\to \pi^\mp K^\pm$ and $B^\pm\to \pi^0 K^\pm$ modes, the large $B^0\to\pi^0\pi^0$ branching…

高能物理 - 唯象学 · 物理学 2008-11-26 Hsiang-nan Li

We investigate the CP-averaged branching ratios, the polarization fractions, the relative phases, and the CP-violating asymmetries of the penguin-dominated $B \to \phi K_1(1270) $ and $ \phi K_1(1400)$ decays in the perturbative QCD(pQCD)…

高能物理 - 唯象学 · 物理学 2014-11-26 Xin Liu , Zhi-Tian Zou , Zhen-Jun Xiao

Recent CP violation results in B decays suggest that Z penguins may have large weak phase. This can be realized by the four generation (standard) model. Concurrently, B to Xs l+ l- and Bs mixing allow for sizable Vt's* Vt'b only if it is…

高能物理 - 唯象学 · 物理学 2009-11-11 Wei-Shu Hou , Makiko Nagashima , Andrea Soddu

We present results for the \Delta S=2 matrix elements which are required to study neutral kaon mixing in the standard model (SM) and beyond (BSM). We also provide leading chiral order results for the matrix elements of the electroweak…

高能物理 - 格点 · 物理学 2009-11-11 Ronald Babich , Nicolas Garron , Christian Hoelbling , Joseph Howard , Laurent Lellouch , Claudio Rebbi

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…

高能物理 - 唯象学 · 物理学 2010-11-23 M. Neubert , J. L. Rosner

We propose a method to quantify the Standard Model uncertainty in B to K pi decays using the experimental data, assuming that power counting provides a reasonable estimate of the subleading terms in the 1/mb expansion. Using this method, we…

高能物理 - 唯象学 · 物理学 2009-04-06 M. Ciuchini , E. Franco , G. Martinelli , M. Pierini , L. Silvestrini

The decays $B_d\to\pi^+\pi^-$ and $B_s\to K^+K^-$ provide an interesting strategy to extract the CKM angle $\gamma$ at ``second-generation'' $B$-physics experiments of the LHC era. A variant for ``first-generation'' experiments can be…

高能物理 - 唯象学 · 物理学 2010-11-23 Robert Fleischer

Measurements of the combined branching ratios for $B^\pm \to \pi^\pm K$ and $B_d \to \pi^\mp K^\pm$ allow interesting constraints on the CKM angle $\gamma$, the ratio $r \equiv |T'|/|P'|$ of the current-current and penguin operator…

高能物理 - 唯象学 · 物理学 2007-05-23 Robert Fleischer , Thomas Mannel

We compute branching ratios of $B\to K\pi$ decays in the framework of perturbative QCD factorization theorem. Decay amplitudes are classified into the topologies of tree, penguin and annihilation, all of which contain both factorizable and…

高能物理 - 唯象学 · 物理学 2009-07-09 Y. -Y. Keum , H. -n. Li , A. I. Sanda

Rare B decays of the type $b \to s~\ell^+\ell^-(\nu\bar\nu)$ are analyzed in a generic scenario where New Physics effects enter predominantly via $Z$ penguin contributions. We show that this possibility is both phenomenologically allowed…

高能物理 - 唯象学 · 物理学 2007-05-23 Gino Isidori

In this presentation, we discuss recent key topics in theoretical analyses of CP violation in benchmarks decays of the $B$ meson. We provide the most updated values of the mixing phases and discuss the importance of including the penguin…

高能物理 - 唯象学 · 物理学 2024-02-28 Eleftheria Malami

We build a set of new observables using closely related non-leptonic penguin-mediated $B_d$ and $B_s$ decays: ${\bar B}_{d,s}\to K^{*0}\bar{K}^{*0}$, ${\bar B}_{d,s}\to K^{0}\bar{K}^{0}$, ${\bar B}_{d,s}\to K^{0}\bar{K}^{*0}$ and ${\bar…

高能物理 - 唯象学 · 物理学 2023-07-05 Aritra Biswas , Sebastien Descotes-Genon , Joaquim Matias , Gilberto Tetlalmatzi-Xolocotzi

We reanalyze the decay $B_d\to\pi^+\pi^-$ without assuming dominance of QCD penguins with internal top-quark exchanges. In that case the weak phase of the $\bar b \to\bar d$ QCD penguin amplitude is not related in a simple way to the CKM…

高能物理 - 唯象学 · 物理学 2009-10-28 Robert Fleischer , Thomas Mannel

We study CP asymmetries in penguin-induced b -> s\bar{s}s decays in general left-right models without imposing manifest or pseudomanifest left-right symmetry. Using the effective Hamiltonian approach, we evaluate CP asymmetries in B^\pm ->…

高能物理 - 唯象学 · 物理学 2011-03-23 Soo-hyeon Nam

The recently observed $B^-\to K^- \pi^0$, $\bar K^0 \pi^-$ and $\bar B^0 \to K^- \pi^+$ decay modes appear to have nearly equal branching ratios. This suggests that tree and electroweak penguins play an important role, and inclusion of the…

高能物理 - 唯象学 · 物理学 2009-10-31 Deshpande , Xiao-Gang He , Wei-Shu Hou , Pakvasa

It is argued that, in the presence of soft final-state interactions, the diagrammatic amplitude approach adopted in many analyses of hadronic B decays into light mesons can be misleading when used to deduce the unimportance of certain decay…

高能物理 - 唯象学 · 物理学 2010-11-23 Matthias Neubert

We report observations of the b --> d penguin-dominated decays B+ --> K0bar K+ and B0 --> K0 K0bar in approximately 350 million Upsilon(4S) --> BBbar decays collected with the BaBar detector. We measure the branching fractions B(B+ -->…

高能物理 - 实验 · 物理学 2010-03-19 The BABAR Collaboration , B. Aubert