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Related papers: QED effects in the pseudoscalar meson sector

200 papers

A brief review of the isospin symmetry breaking in hadrons and nuclei is given with emphasis on the $u-d$ quark mass difference. The off-shell $\rho^0-\omega$ mixing is studied as a typical example of the symmetry breaking, and its…

High Energy Physics - Phenomenology · Physics 2009-10-28 Tetsuo Hatsuda

Following the 1999 analysis of Gambino, Haisch and one of us, we stress that all the recent NLO analyses of $\varepsilon'/\varepsilon$ in the Standard Model (SM) suffer from the renormalization scheme dependence present in the electroweak…

High Energy Physics - Phenomenology · Physics 2020-01-29 Jason Aebischer , Christoph Bobeth , Andrzej J. Buras

We discuss the consequences of the approximate conservation of the vector and axial currents for the hadronic matrix elements appearing in beta decay if non-standard interactions are present. In particular the isovector (pseudo)scalar…

High Energy Physics - Phenomenology · Physics 2014-02-05 Martín González-Alonso , Jorge Martin Camalich

This work focuses on decomposition of isospin amplitude of D meson non-leptonic decays. Isospin vector algebra is used to show the equivalency of two amplitude decompositions. We restrict to the transitions involving only Del I = 1 and Del…

High Energy Physics - Phenomenology · Physics 2023-11-27 Shakeel Mahmood , Mudassir Hussain , Abrar Ahmad

We analyze isospin breaking through quark mass differences and virtual photons in the pion-nucleon scattering lengths in all physical channels in the framework of covariant baryon chiral perturbation theory. The so-called triangle relation…

High Energy Physics - Phenomenology · Physics 2014-11-20 Martin Hoferichter , Bastian Kubis , Ulf-G. Meißner

The mass differences in all neutral pseudo scalar mesons and CP violations associated with the mixings are investigated in the context of the fermion- boson-type subquark model. These phenomena are unifyingly explained by the neutral scalar…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. Matsushima

Effects of CP violation and of final state interactions between pairs of pseudoscalar mesons are studied in three-body B+, B-, B0 and antiB0 decays into K pi pi. An alternative approach to the isobar model for three-body B decays is…

High Energy Physics - Phenomenology · Physics 2008-11-26 L. Lesniak , B. El-Bennich , A. Furman , R. Kaminski , B. Loiseau , B. Moussallam

In the first part of these lectures, I consider chiral perturbation theory in the presence of matter fields. It allows to systematically work out the consequences of the broken chiral symmetry of QCD. As examples, threshold pion photo- and…

High Energy Physics - Phenomenology · Physics 2015-06-25 Ulf-G. Meißner

The decays of $D$ mesons to $K l \nu$ and $K^* l \nu$ final states exhibit significant deviations from the predictions of heavy-quark symmetry, as one might expect since the strange quark's mass is of the same order as the QCD scale.…

High Energy Physics - Phenomenology · Physics 2009-10-22 James F. Amundson , Jonathan L. Rosner

Within the realm of QCD sum rules, one of the most important areas of application of this nonperturbative approach is the prediction of the decay constants of heavy mesons. However, in spite of the fact that, indisputably, the adopted…

High Energy Physics - Phenomenology · Physics 2016-01-26 Wolfgang Lucha , Dmitri Melikhov , Silvano Simula

We calculate the nucleon self-energies in isospin-asymmetric nuclear matter using QCD sum rules. Taking the difference of these for the neutron and proton enables us to express the potential part of the nuclear symmetry energy in terms of…

Nuclear Theory · Physics 2015-03-20 Kie Sang Jeong , Su Houng Lee

The $\tau^- \to \pi^-\eta\nu_{\tau}$ decay is forbidden in the Standard Model in the limit of exact $G$-parity, it becomes a rare decay due to isospin symmetry breaking and it is very sensitive to the effects of effective scalar…

High Energy Physics - Phenomenology · Physics 2024-02-08 Gerardo Hernández-Tomé , Gabriel López Castro , Diego Portillo-Sánchez

We use the Isospin Quantum Molecular Dynamics model (IQMD) to analyze the centrality dependence of the isospin ratio of pions, $\pi^-/\pi^+$. We find that the density dependence of the asymmetry potential, the Pauli blocking of the…

Nuclear Theory · Physics 2018-08-30 C. Hartnack , A. Le Fevre , Y. Leifels , J. Aichelin

Effects of the isospin-symmetry breaking (ISB) beyond mean-field Coulomb terms are systematically studied in nuclear masses near the $N=Z$ line. The Coulomb exchange contributions are calculated exactly. We use extended Skyrme energy…

We consider an extension of the finite-temperature Dyson-Schwinger equation (DSE) approach to heavy mesons and quarkonia and apply it to calculate the cross section for the J/Psi breakup reaction J/Psi + pi --> D + D. We study the effects…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. B. Blaschke , G. R. G. Burau , M. A. Ivanov , Yu. L. Kalinovsky , P. C. Tandy

We propose a model of soft CP violation that evades the strong CP problem and can describe observed CP violation in the neutral kaon sector, both direct and indirect. Our model requires two ``duark'' mesons carrying quark number two that…

High Energy Physics - Phenomenology · Physics 2017-08-23 Paul H. Frampton

We investigate to what extent the recently measured value for a non-vanishing direct CP asymmetry in D0 -> K+ K- and D0 -> pi+ pi- decays can be accommodated in the Standard Model (SM) or extensions with a constrained flavour sector, for…

High Energy Physics - Phenomenology · Physics 2015-06-04 Thorsten Feldmann , Soumitra Nandi , Amarjit Soni

We discuss the electroproduction of pseudoscalar ($0^{-+}$) or scalar ($0^{++}$) meson production off the scalar target. The most general formulation of the differential cross section for the $0^{-+}$ or $0^{++}$ meson production process…

Nuclear Theory · Physics 2019-06-19 Chueng-Ryong Ji , Ho-Meoyng Choi , Andrew Lundeen , Bernard L. G. Bakker

We investigate the QCD phase diagram for small values of baryon and strange quark chemical potentials from simulations at non-zero isospin chemical potential. Simulations at pure isospin chemical potential are not hindered by the sign…

High Energy Physics - Lattice · Physics 2019-11-28 Bastian B. Brandt , Francesca Cuteri , Gergely Endrodi , Sebastian Schmalzbauer

The parity-violating asymmetry, including leading-order QED corrections to the Coulomb potential, is calculated non-perturbatively by solving the Dirac equation. At GeV collision energies and forward scattering angles, QED effects enhance…

Nuclear Theory · Physics 2025-05-14 Xavier Roca-Maza , D H. Jakubassa-Amundsen