English
Related papers

Related papers: Measuring gamma in B -> K pi pi Decays

200 papers

The large ratio of color-suppressed tree amplitude to color-allowed one in $B \to \pi \pi$ decays is difficult to understand within the Standard Model, which is known as the "$B \to \pi\pi$ puzzle". The two tree diagrams contain the up- and…

High Energy Physics - Phenomenology · Physics 2008-11-26 Seungwon Baek

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

The theory of $CP$ violation based on phases in weak couplings in the Cabibbo-Kobayashi-Maskawa (CKM) matrix requires the phase $\gamma \equiv {\rm Arg~} V^*_{ub}$ (in a standard convention) to be nonzero. A measurement of $\gamma$ is…

High Energy Physics - Phenomenology · Physics 2009-09-25 Michael Gronau , Jonathan L. Rosner , David London

We suggest two methods (based on flavor SU(3) symmetry) to determine the CKM angle $\gamma$ using the decays $B_d$, $B^+ \to K \eta (\eta')$ and $B_s \to \pi \eta (\eta')$, respectively. Rescattering effects are partly included -- we…

High Energy Physics - Phenomenology · Physics 2010-11-23 K. Agashe , N. G. Deshpande

The considerable influx of new data on B decays offers opportunities to determine some of the smaller contributions to the decay process, such as suppressed diagrams, and to test the relations between decay amplitudes implied by (broken)…

High Energy Physics - Phenomenology · Physics 2007-05-23 Timothy Carruthers , Bruce H J McKellar

Isospin analysis has been used to constrain the CP-asymmetries in B -> pi pi decays. In particular correlation between a weak phase \theta and a strong phase \delta is obtained. Further using the experimental values for the CP-average…

High Energy Physics - Phenomenology · Physics 2007-05-23 Fayyazuddin

An improved flavor SU(3) method is presented for determining the weak angle $\gamma$ of the unitarity triangle using decay rates for $B^+\to K\pi, B^+\to K^+\bar K^0$ and $B^+\to \pi^+\eta$ (or $B^0\to K\pi$ and $B_s\to K \pi$), their…

High Energy Physics - Phenomenology · Physics 2014-11-17 Michael Gronau , Dan Pirjol

Theoretical errors in the extraction of alpha from B -> pi^+ pi^-, rho^+ rho^-, rho pi decays are usually given in terms of upper bounds on alpha_eff-alpha obtained from isospin or from SU(3) relations, where alpha_eff is measured through…

High Energy Physics - Phenomenology · Physics 2010-04-05 M. Gronau , E. Lunghi , D. Wyler

We present strategies for determining electroweak penguins from experimental data. Using the CKM-angle $\gamma$ as one of our central inputs and making some reasonable approximations, we show that the $\bar b\to\bar s$ electroweak penguin…

High Energy Physics - Phenomenology · Physics 2009-10-28 Andrzej J. Buras , Robert Fleischer

We study the determination of gamma from CP-violating observables in B -> pi+ pi- and B -> psi K_S. This determination requires theoretical input to one combination of hadronic parameters. We show that a mild assumption about this quantity…

High Energy Physics - Phenomenology · Physics 2009-11-10 F. J. Botella , Joao P. Silva

We study decay distributions in B -> K pi pi gamma, combining contributions from several overlapping resonances in a K pi pi mass range near 1400 MeV, (1^+) K_1(1400), (2^+) K^*_2(1430) and (1^-) K^*(1410). A method is proposed for using…

High Energy Physics - Phenomenology · Physics 2009-11-07 Michael Gronau , Dan Pirjol

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 discuss a possibility of large electroweak(EW) penguin contribution in B-->K pi and pi pi. The recent experimental data may be still suggesting that there are some discrepancies between the data and theoretical estimations. In B --> K pi…

High Energy Physics - Phenomenology · Physics 2007-05-23 Satoshi Mishima , Tadashi Yoshikawa

We measure the branching fraction of the radiative B- decay B(B- -> phi K- gamma) = (3.46 +/- 0.57^{+0.39}_{-0.37}) 10^-6, and set an upper limit on the radiative B0 decay B(B0 -> phi K0 gamma) < 2.71 10^-6 at 90% confidence level. We also…

High Energy Physics - Experiment · Physics 2007-05-23 The BABAR Collaboration , B. Aubert

We have searched for the K+ to pi+ gamma gamma decay in the kinematic region with pi+ momentum close to the end point. No events were observed, and the 90% confidence-level upper limit on the partial branching ratio was obtained, B(K+ to…

High Energy Physics - Experiment · Physics 2008-11-26 E949 Collaboration , A. V. Artamonov

The influence of strong and electroweak penguin amplitudes in $B/ \bar B \rightarrow \pi^+\pi^-$ is investigated in connection with the determination of the unitarity triangle angle $\alpha$ of the CKM matrix. A relation between the…

High Energy Physics - Phenomenology · Physics 2009-09-25 G. Kramer , W. Palmer , Y. L. Wu

We present a method of obtaining the entire unitarity triangle from measurements of B -> pi K decay rates alone. Electroweak penguin amplitudes are included, and are related to tree operators. Discrete ambiguities are removed by comparing…

High Energy Physics - Phenomenology · Physics 2009-11-10 Maxime Imbeault , Veronique Page , Alexandre St-Laurent Lemerle , David London

We present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B -> K pi pi gamma in the range m_Kpipi < 1.8 GeV/c^2. We reconstruct four final states: K+ pi- pi+ gamma, K+ pi- pi0…

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

We report improved measurements of branching fractions for B -> K pi and B -> pi pi decays based on a data sample of 449 million B Bbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB e^+e^- collider. We…

High Energy Physics - Experiment · Physics 2019-08-14 S. -W. Lin , P. Chang

The first observation of the decay K^+ --> pi^+ gamma gamma is reported. A total of 31 events was observed with an estimated background of 5.1 +- 3.3 events in the pi+ momentum range from 100 MeV/c to 180 MeV/c. The corresponding partial…