oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Search Results: 1 - 10 of 3290 matches for " Johan Bijnens "
All listed articles are free for downloading (OA Articles)
Page 1 /3290
Display every page Item
Radiative and semileptonic decays in Chiral Perturbation Theory
Bijnens, Johan
High Energy Physics - Phenomenology , 2007,
Abstract: I give a short overview of what has been done in radiative and semileptonic Kaon decays in Chiral Perturbation Theory. This includes for semileptonic decays the work which has been done to order $p^6$ including preliminary results of isospin breaking to that order in $K_{\ell3}$. For the radiative decays I mainly present some results from recent work concerning $K_{\ell3\gamma}$.
Chiral Perturbation Theory and Mesons
Bijnens, Johan
High Energy Physics - Phenomenology , 2013,
Abstract: The talk contains a short introduction to mesonic Chiral Perturbation Theory (ChPT). In addition four disparate areas where some progress has been made in recent years are discussed. These are the last fit of the order $p^4$ low-energy-constants $L_i^r$ to data, hard pion ChPT, the recent two-loop work on EFT for QCD like theories and the high order leading logarithm calculations in the massive $O(N)$ nonlinear sigma model.
Quark Mass dependence at Two Loops for Meson Properties
Bijnens, Johan
High Energy Physics - Phenomenology , 2007,
Abstract: This talks contains a short introduction to Chiral Perturbation Theory and the existing calculations to two-loop order in the mesonic sector. I include a discussion on which quantities the expansion can be organized in. The present best values of the Low-Energy-Constants as determined from continuum physics are given as well as the assumptions underlying the fits to experimental data. I present plots of masses, decay constants and $f_+(0)$ in $K_{\ell3}$ as a function of quark or meson masses. The talk ends with a list of things for which it would be extremely useful to have good results from lattice QCD calculations.
Eta and Eta' physics
Bijnens, Johan
High Energy Physics - Phenomenology , 2007,
Abstract: This talk describes the reasons why $\eta$ and $\eta^\prime$ decays are an interesting topic of study for both theory and experiment. The main part discusses the results of the recent calculation of $\eta\to3\pi$ at two-loop order in ChPT. Some puzzling aspects of the results compared to earlier dispersive calculations are highlighted. I also like to remind the reader of the use of $\eta$ and $\eta^\prime$ decays for studying the anomaly.
Chiral Lagrangians and Nambu-Jona-Lasinio like models
Johan Bijnens
Physics , 1995, DOI: 10.1016/0370-1573(95)00051-8
Abstract: We discuss the low-energy analysis of models involving quarks and four-fermion couplings. The relation with QCD and with other models of mesons and meson plus quarks at low energies is discussed. A short description of how the heat-kernel expansion can be used to get regularization independent information, is given. The anomaly within this class of models and a physical prescription to obtain the correct flavour anomaly while keeping as much of the VMD aspects as possible is discussed. The major part is the discussion within this framework of the order $p^4$ action and of two and some three-point functions to all orders in momenta and quark masses. Some results on hadronic matrix elements are given.
Chiral Perturbation Theory
Johan Bijnens
Physics , 1995,
Abstract: A short overview of the current state of Chiral Perturbation Theory is given. This includes a description of the basic assumptions, the usefulness of the external field method is emphasized using a simple lowest order example. Then at next-to-leading order the determination of the parameters is discussed. We also present the status of calculations at ${\cal O}(p^6)$. Finally I present the extension into 3 directions: estimates of the free parameters, inclusion of nonleptonic weak and electromagnetic interactions, and inclusion of non-Goldstone fields in the chiral Lagrangian. Invited Talk at the International Workshop on Nuclear \& Particle Physics ``Chiral Dynamics in Hadrons \& Nuclei,'' Feb 6 $\sim$ Feb 10, 1995, Seoul, Korea.
Eta and Eta' physics
Johan Bijnens
Physics , 2007,
Abstract: This talk describes the reasons why $\eta$ and $\eta^\prime$ decays are an interesting topic of study for both theory and experiment. The main part discusses the results of the recent calculation of $\eta\to3\pi$ at two-loop order in ChPT. Some puzzling aspects of the results compared to earlier dispersive calculations are highlighted. I also like to remind the reader of the use of $\eta$ and $\eta^\prime$ decays for studying the anomaly.
Effective Lagrangians for Light Quarks
Johan Bijnens
Physics , 1994,
Abstract: The class of phenomenological Lagrangians used for light constituent quarks is discussed. The Nambu-Jona-Lasinio model is then argued to be a good phenomenological choice and the quality of its prediction in the purely hadronic sector including several relations between parameters illustrated. Then we use these models to calculate nonleptonic matrix elements. The $\pi^+-\pi^0$ mass difference and the $B_K$ parameter, relevant in $K^0-\overline{K}^0$ mixing, are treated in more detail.
Introduction to Extended Nambu-Jona-Lasinio Models
Johan Bijnens
Physics , 1994,
Abstract: A short introduction to quark models with four fermion terms and their predictions for the parameters of low-energy effective Lagrangians is given. Special attention is paid to predictions that are as general as possible. Contribution to the Second DAPHNE Physics Handbook, eds. L. Maiani, G. Pancheri and N. Paver.
Quark Mass dependence at Two Loops for Meson Properties
Johan Bijnens
Physics , 2007,
Abstract: This talks contains a short introduction to Chiral Perturbation Theory and the existing calculations to two-loop order in the mesonic sector. I include a discussion on which quantities the expansion can be organized in. The present best values of the Low-Energy-Constants as determined from continuum physics are given as well as the assumptions underlying the fits to experimental data. I present plots of masses, decay constants and $f_+(0)$ in $K_{\ell3}$ as a function of quark or meson masses. The talk ends with a list of things for which it would be extremely useful to have good results from lattice QCD calculations.
Page 1 /3290
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.