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We show that ratios of tree and penguin amplitudes in B-> K*pi and B->rho K are two to three times larger than in B-> K pi. This allows for considerably larger CP asymmetries in the former processes than the 10% asymmetry measured in B0 ->…

High Energy Physics - Phenomenology · Physics 2010-05-25 Michael Gronau , Dan Pirjol , Jure Zupan

The CLEO collaboration has recently reported a (first) measurement of $BR (B \to \pi^+ \pi^-) = (4.7^{+1.8}_{-1.5} \pm 0.6) \times 10^{-6}$. We study, using recent results on QCD improved factorization, the implications of this measurement…

High Energy Physics - Phenomenology · Physics 2009-12-30 K. Agashe , N. G. Deshpande

From a time-dependent analysis of the decay $B^0_{d} \to \pi^+ \pi^-$ and using a model-dependent $A_P/A_T$ ratio of the penguin-to-tree amplitudes contributing to the decay, both the weak phase $\alpha$ and the strong phase shift…

High Energy Physics - Phenomenology · Physics 2014-11-17 Pier S. Marrocchesi , Nello Paver

We discuss about a possibility of large electroweak penguin contribution in B -> K pi and pi pi from recent experimental data. The experimental data may be suggesting that there are some discrepancies between the data and theoretical…

High Energy Physics - Phenomenology · Physics 2016-09-06 Satoshi Mishima , Tadashi Yoshikawa

The measurements of B -> pi K decays have been in disagreement with the predictions of the Standard Model (SM) for some time. In this paper, we perform an update of this puzzle using the latest (2008) data. We find that the situation has…

High Energy Physics - Phenomenology · Physics 2014-11-18 Seungwon Baek , Cheng-Wei Chiang , David London

An enhanced electroweak penguin amplitude due to the presence of unknown new physics can explain the discrepancies found between theory and experiment in the B -> pi K decays, in particular in A_CP(B^- -> pi^0 K^-) - A_CP(\bar{B}^0 -> pi^+…

High Energy Physics - Phenomenology · Physics 2015-05-28 Lars Hofer , Dominik Scherer , Leonardo Vernazza

The CP asymmetry in $B^0\to K^+\pi^-$ is expected to be similar to that in $B^+\to K^+\pi^0$. The experimental data however show $\sim 5\sigma$ difference between the two, leading to the so called $\Delta {A}_{K\pi}$ puzzle. Employing sum…

High Energy Physics - Phenomenology · Physics 2008-12-02 Namit Mahajan

Time-dependence in $B^0(t) \to \pi^+ \pi^-$ and $\ob(t) \to \pi^+ \pi^-$ is utilized to obtain a maximal set of information on strong and weak phases. One can thereby check theoretical predictions of a small strong phase $\delta$ between…

High Energy Physics - Phenomenology · Physics 2009-11-07 Michael Gronau , Jonathan L. Rosner

The 2.5 sigma discrepancy between theory and experiment observed in the difference A_CP(B^- --> pi^0 K^-)-A_CP(Bbar^0 --> pi^+ K^-) can be explained by a new electroweak penguin amplitude. Motivated by this result, we analyse the purely…

High Energy Physics - Phenomenology · Physics 2015-03-17 Lars Hofer , Dominik Scherer , Leonardo Vernazza

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…

High Energy Physics - Phenomenology · Physics 2009-10-31 Deshpande , Xiao-Gang He , Wei-Shu Hou , Pakvasa

We calculate CP-violating rates and asymmetry parameters in charged and neutral $B\to \pi\pi, \pi K$ and $\bar K K$ decays arising from the interference of tree and penguin (strong and electroweak) amplitudes with different strong and CKM…

High Energy Physics - Phenomenology · Physics 2009-10-28 G. Kramer , W. Palmer

Employing the standard hard-scattering approach and the running coupling method we calculate a class of power-suppressed corrections $\sim 1/Q^{2n},n=1,2,3,...$ to the electromagnetic $\pi^0\gamma$ transition form factor (FF)…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. S. Agaev

This letter is an investigation of the pion form factor utilizing recently developed effective field theory techniques. The primary results reported are: Both the transition and electromagnetic form factors are corrected at order…

High Energy Physics - Phenomenology · Physics 2009-11-10 Ira Z. Rothstein

We show that there exist uncanceled soft divergences in the k_T factorization for nonfactorizable amplitudes of two-body nonleptonic B meson decays, similar to those identified in hadron hadroproduction. These divergences can be grouped…

High Energy Physics - Phenomenology · Physics 2011-03-23 Hsiang-nan Li , Satoshi Mishima

The $B\to\pi\pi,\pi K$ system offers a powerful laboratory to probe strong and weak interactions. Using the isospin symmetry, we determine hadronic $B\to\pi\pi$ parameters from data where new measurements of direct CP violation in…

High Energy Physics - Phenomenology · Physics 2018-12-05 Robert Fleischer , Ruben Jaarsma , Eleftheria Malami , K. Keri Vos

Though QCD Factorization(QCDF) could produce sufficiently large $B\to K\pi$ branching ratios close to experiments, the predicted direct CP asymmetry in ${\bar B}^{0}\to K^{+}\pi^{-}$ decay is however still quite below experiment, even with…

High Energy Physics - Phenomenology · Physics 2009-10-19 T. N. Pham

We investigate allowed regions in observable space of B --> pi K, B_d --> pi^+pi^- and B_s --> K^+K^- decays, characterizing these modes in the Standard Model. After a discussion of a new kind of contour plots for the $B\to\pi K$ system, we…

High Energy Physics - Phenomenology · Physics 2011-03-23 Robert Fleischer , Joaquim Matias

The present B -> pi K data is studied in the context of the standard model (SM) and with new physics (NP). We confirm that the SM has difficulties explaining the B -> pi K measurements. By adopting an effective-lagrangian parametrization of…

High Energy Physics - Phenomenology · Physics 2009-11-10 Seungwon Baek , Philippe Hamel , David London , Alakabha Datta , Denis A. Suprun

Power corrections seem to play an important role in charmless B decays as indicated by recent analysis using QCD Factorization. In this talk, I would like to report on a recent work on power corrections in charmless B decays. By using the…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. N. Pham

Direct CP violation in B^0-> K^+\pi^- decay has emerged at -10% level, but the asymmetry in B^+ -> K^+\pi^0 mode is consistent with zero. This difference points towards possible New Physics in the electroweak penguin operator. We point out…

High Energy Physics - Phenomenology · Physics 2009-11-11 Wei-Shu Hou , Makiko Nagashima , Andrea Soddu