نتایج جستجو برای: ππ interactions

تعداد نتایج: 389020  

2001
Michael Gronau

We report on recent progress in studying two aspects of B physics, in which penguin amplitudes play an important role: 1. Bounds on penguin pollution in B(t) → ππ constraining the CKM parameters ρ and η, and a lower bound on B → ππ improving precision in sin 2α. 2. A suggestion for measuring the photon polarization in electroweak penguin decay, B → K1(1400)γ, providing a test of the Standard Mo...

2001
I. V. Anikin

We present the alternative way of derivation of the Wandzura-Wilczek relations between the kinematical twist-3 and twist-2 functions, parameterizing hadronic matrix element in two-photon processes γπ → γπ and γγ → ππ. The new equations, providing the independence of the physical cross-sections on the choice of the light-cone direction, are suggested and explored. The amplitude of γγ → ππ up to ...

1998
K. Terasaki

K → ππ, KL-KS mass difference, KL → γγ and the Dalitz decays of KL are studied systematically by assuming that their amplitude can be described in terms of a sum of short distance and long distance contributions. Dominance of the short distance effect on the KL-KS mass difference will be checked by the Dalitz decays of KL in a way consistent with the K → ππ and KL → γγ decays.

2002
Yong-Yeon Keum

We look at methods to determine the weak phases φ2 and φ3 from B → ππ and Kπ decays within the perturbative QCD approach. We obtain quite interesting bounds on φ2 and φ3 from experimental measurement in B-factory: 55 ≤ φ2 ≤ 100 and 51 ≤ φ3 ≤ 129. Specially we predict the possibility of large direct CP violation effect in B → ππ (23± 7%) decay. DPNU-02-28 hep-ph/0209002

1993
Sumantra Chakravarty Sun Myong Kim

Assuming the QCD multipole expansion is applicable to hadronic transitions of Υ(3S) into lower level bottomonia, we consider the possibility that Υ(3S) has a D−wave component. This assumption leads to a natural explanation of the ππ spectrum in Υ(3S) → Υ(1S) ππ. Consequences of this assumption on other hadronic and radiative transitions of Υ(3S) are also discussed in the same context. PACS numb...

1996
K. Takamatsu

In the previous work, analyzing the I=0 S-wave ππ-scattering phase-shift through a new method of Interfering Breit-Wigner amplitudes, we have shown possibility of existence of a light scalar, σ particle, by assuming a negative back-ground phaseshift, corresponding to “repulsive core” in ππ-interaction. In this work we investigate further, to what extent, σ-properties and size of core radius are...

2006
A. Matsuyama H. Lee

a Department of Physics, Shizuoka University, Shizuoka 422-8529, Japan b Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan c Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 Abstract A dynamical coupled-channel model is presented for investigating the nucleon resonances (N∗) in the meson production reactions induced by pions and photons. Our objectiv...

2002
Dilip Kumar Ghosh Jian-Qing Shi

We study contributions of quark-squark-gluino interactions in Minimal Supersymmetric Standard Model (MSSM) to B → PP (PP = Kπ, ππ,KK) decays using QCD improved factorization method for the evaluation of the hadronic matrix elements and taking into account renormalization group running of the Wilson coefficients from SUSY scale (≈ mq̃) to the low energy scale (= mb) applicable to B decays. Using ...

1999
V. E. Markushin

The analysis of the poles of the ππ scattering amplitude is shown to favour a dynamical origin of the sigma meson: it is created by a strongly attractive ππ interaction in the J = 0I = 0 channel. In the limit Nc → ∞, the σ meson disappears, contrary to the case of conventional qq̄ states. Implications for the search of the scalar qq̄ and glueball states are discussed.

1997
Y. Iwasaki K. Kanaya Y. Kuramashi

A new study is reported of a lattice QCD calculation of the K → ππ decay amplitude with the Wilson quark action in the quenched approximation at β = 6.1. The amplitude is extracted from the K → ππ Green function, and a conversion to the continuum value is made employing a recent one-loop calculation of chiral perturbation theory. The result is consistent with the experimental value if extrapola...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید