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Related papers: The pionic beta decay in chiral perturbation theor…

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We analyze the second-class current decays $\tau^{-}\to\pi^{-}\eta^{(\prime)}\nu_{\tau}$ in the framework of Chiral Perturbation Theory with resonances. Taking into account $\pi^{0}$-$\eta$-$\eta^{\prime}$ mixing, the…

High Energy Physics - Phenomenology · Physics 2016-08-08 Rafel Escribano , Sergi Gonzalez-Solis , Pablo Roig

The dominant decay mode of the eta-prime, eta-prime -> eta pi pi, is investigated within the framework of infrared regularized U(3) chiral perturbation theory up to fourth chiral order and including one-loop corrections. We find reasonable…

High Energy Physics - Phenomenology · Physics 2011-03-23 N. Beisert , B. Borasoy

A calculation of the Dalitz decay in next-to-leading order in chiral perturbation theory of two flavour case extended by virtual photons is presented. The whole kinematic sector is covered and realistic experimental situation is discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 K. Kampf , M. Knecht , J. Novotny

We calculate the pion-pion elastic scattering phase shifts for pion masses from the chiral limit to values of interest for lattice studies. At low energies, we use the standard Chiral Perturbation Theory expressions to one and two loops. In…

High Energy Physics - Phenomenology · Physics 2011-10-11 J. Nebreda , J. R. Pelaez , G. Rios

We study the effects of the $\Delta$(1232) resonance as an effective degree of freedom for charged and neutral pion photo-production on nucleons. Different observables have been calculated for these processes by using relativistic chiral…

High Energy Physics - Phenomenology · Physics 2019-11-27 Gustavo H. Guerrero Navarro

I discuss isospin breaking effects within the standard model. Chiral perturbation theory presents the appropriate theoretical framework for such an investigation in the low--energy range. Recent results on the electromagnetic contributions…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. Neufeld

We present three analyses based on data samples collected by the Belle detector at the KEKB e+e- asymmetric energy collider. The first one contains the measurement of the branching fractions and q^2 distributions of exclusive charmless…

High Energy Physics - Experiment · Physics 2008-10-07 Wolfgang Dungel

CKM matrix is unitary by construction in the standard model(SM). The recent analyses on the first row of CKM matrix show $ \approx 3\sigma$ tension with unitarity. Nonperturbative calculations of the radiative corrections can reduce the…

High Energy Physics - Lattice · Physics 2022-12-27 Jun-Sik Yoo , Tanmoy Bhattacharya , Rajan Gupta , Santanu Mondal , Boram Yoon

We briefly summarize up-to-date results on the determination of the parameters of the Cabibbo-Kobayashi-Maskawa matrix $|V_{cb}|$ and $|V_{ub}|$, which play an important role in the unitarity triangle and in testing the Standard Model, and…

High Energy Physics - Phenomenology · Physics 2018-08-29 Giulia Ricciardi

The result of lowest-order perturbation theory calculations of the photon and positron spectra in radiative pion(e2) decay are generalized to all orders of perturbation theory using the structure-function method. An additional source of…

High Energy Physics - Phenomenology · Physics 2009-10-30 E. A. Kuraev

The element |V_{ub}| of the quark mixing matrix can be extracted with small theoretical uncertainties by combining weighted integrals over the endpoint regions of the lepton spectrum in B -> X_u l nu decays and the photon spectrum in B ->…

High Energy Physics - Phenomenology · Physics 2014-11-17 Matthias Neubert

We present a comprehensive study of the electromagnetic form factor, the decay constant and the mass of the pion computed in lattice QCD with two degenerate O(a)-improved Wilson quarks at three different lattice spacings in the range…

High Energy Physics - Lattice · Physics 2015-06-16 Bastian B. Brandt , Andreas Juttner , Hartmut Wittig

We propose a model-independent parametrization for the one-pion-to-vacuum matrix elements of the vector and axial vector hadronic currents in the presence of an external uniform magnetic field. It is shown that, in general, these hadronic…

High Energy Physics - Phenomenology · Physics 2019-08-29 M. Coppola , D. Gomez Dumm , S. Noguera , N. N. Scoccola

The value of the V_{ud} matrix element of the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be derived from nuclear superallowed beta decays, neutron decay, and pion beta decay. We survey current world data for all three. Today, the most…

Nuclear Theory · Physics 2008-11-07 I. S. Towner , J. C. Hardy

We perform a relativistic chiral effective field theory calculation of the radiative pion photoproduction ($\gamma p \to \pi^0 p \gamma'$) in the $\Delta$-resonance region, to next-to-leading order in the ``delta-expansion''. This work is…

Nuclear Theory · Physics 2014-11-18 Vladimir Pascalutsa , Marc Vanderhaeghen

We make use of recent accurate results obtained for the pion and kaon vector form factors within a chiral unitary approach in order to calculate the decay widths of the $\tau$ lepton to these mesons and also to evaluate the contribution of…

High Energy Physics - Phenomenology · Physics 2009-11-07 J. E. Palomar

We analyse tau -> (3 pions) nu_tau decays within the framework of the resonance chiral theory of QCD. We have worked out the relevant Lagrangian that describes the axial-vector current hadronization contributing to these processes, and the…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Gomez Dumm , A. Pich , J. Portoles

We review recent experimental progress in the domain of rare radiative, semileptonic and leptonic B decays. The statistical precision attained for these decays has reached a level where they start to impose meaningful constraints on the…

High Energy Physics - Experiment · Physics 2007-05-23 Thomas Schietinger

We present two-loop calculations on the axial-vector form factors $F_A$ of semileptonic radiative kaon and pion decays in chiral perturbation theory. The relevant dimension-6 terms of the lagrangian are evaluated from the resonance…

High Energy Physics - Phenomenology · Physics 2009-11-10 C. Q. Geng , I-Lin Ho , T. H. Wu

The electric ${\alpha}_{\pi}$ and magnetic $\beta_{\pi}$ charged pion Compton polarizabilities are of fundamental interest in the low-energy sector of quantum chromodynamics (QCD).They are directly linked to the phenomenon of spontaneously…

High Energy Physics - Phenomenology · Physics 2018-06-19 Murray Moinester
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