English
Related papers

Related papers: Weakly-induced strong CP-violation

200 papers

Thanks to the unnaturally small value of the QCD vacuum angle $\bar\theta < 10^{-10}$, time-reversal ($T$) violation offers a window into physics beyond the Standard Model (SM) of particle physics. We review the effective-field-theory…

High Energy Physics - Phenomenology · Physics 2015-05-26 E. Mereghetti , U. van Kolck

We discuss a class of models in which CP is violated softly in a heavy sector adjoined to the standard model. Heavy-sector loops produce the observed CP violation in kaon physics, yielding a tiny and probably undetectable value for…

High Energy Physics - Phenomenology · Physics 2009-09-11 Howard Georgi , Sheldon L. Glashow

We investigate chiral symmetry breaking and strong CP violation effects in the phase diagram of strongly interacting matter. We demonstrate the effect of strong CP violating terms on the phase structure at finite temperature and densities…

High Energy Physics - Phenomenology · Physics 2015-06-03 Bhaswar Chatterjee , Hiranmaya Mishra , Amruta Mishra

We focus on a powerful aspect of chiral perturbation theory (chi PT) which provides us with a ``bridge'' over different reactions. For this purpose, we study a contact operator which contributes p-wave pi-production and several weak…

Nuclear Theory · Physics 2008-11-26 Satoshi. X. Nakamura

It has been pointed out recently that a certain set of dimension-6 scalar $P$- and $CP$-violating light-quark-muon operators may be tested in $\eta$ and $\eta'$ decays to various final states involving $\mu^+\mu^-$ pairs, at a level not yet…

High Energy Physics - Phenomenology · Physics 2022-12-20 Maximilian Zillinger , Bastian Kubis , Pablo Sánchez-Puertas

We present a calculation of the low energy constants describing the real and imaginary parts of the $K \to \pi \pi$ decay amplitudes $A_0$ and $A_2$. Leading and next leading order chiral perturbation theory is used and its applicability…

High Energy Physics - Lattice · Physics 2010-01-21 Shu Li , Norman H. Christ

The low energy dynamics of the general strongly interacting symmetry breaking sector can be easily described using effective chiral Lagrangians. Indeed, the enhancement in WW scattering at LHC, that would imply the existence of such an…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. R. Pelaez

We study O(alpha^2 beta_0) perturbative corrections to matrix elements entering two-body exclusive decays of the form B -> pi pi, pi K in the QCD factorization formalism, including chirally enhanced power corrections, and discuss the effect…

High Energy Physics - Phenomenology · Physics 2009-11-11 Craig N. Burrell , Alexander R. Williamson

Aiming at a model-independent analysis of possible new physics effects in semileptonic processes at various energy scales, we list and study a complete set of $SU(3)_c\times SU(2)_L\times U(1)_Y$ invariant 4-Fermi operators which consist of…

High Energy Physics - Phenomenology · Physics 2007-05-23 We-Fu Chang , John N. Ng

We calculate the chiral and thermal susceptibilities for two confining Dyson-Schwinger equation models of QCD with two light flavours, a quantitative analysis of which yields the critical exponents, beta and delta, that characterise the…

Nuclear Theory · Physics 2008-11-26 D. Blaschke , A. Hoell , C. D. Roberts , S. Schmidt

Discovery of the CP-violation in the lepton sector is one of the challenges of the particle physics. We search for possible principles, symmetries and phenomenological relations that can lead to particular values of the CP-violating Dirac…

High Energy Physics - Phenomenology · Physics 2010-10-27 Y. Farzan , A. Yu. Smirnov

We briefly review the cases of forced and spontaneous chiral symmetry breaking. In particular the chiral condensate of q anti-q pairs is parametrized with two angles, phi which measures the chiral condensation, and theta which measures the…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Bicudo , J. Ribeiro

The theoretical status of direct CP violation $\epsilon'/\epsilon$ is briefly reviewed. Special attention is paid to the recent new consistent predictions for both the ratio $\epsilon'/\epsilon$ and the $\Delta I = 1/2$ rule within the…

High Energy Physics - Phenomenology · Physics 2017-08-23 Yue-Liang Wu

The hadronization structure of $\tau^- \to \eta \pi^- \pi^0 \nu_\tau$ decays is analyzed using Chiral Perturbation Theory with resonances, considering only the contribution of the lightest meson resonances at leading order in the $1/N_C$…

High Energy Physics - Phenomenology · Physics 2013-05-30 Daniel Gómez Dumm , Pablo Roig

The pseudoscalar particles pions, kaons and the $\eta$-particle are considerably lighter than the other hadrons such as protons or neutrons. Their lightness was understood as a consequence of approximate chiral symmetry breaking. This led…

High Energy Physics - Phenomenology · Physics 2023-02-14 B. Ananthanarayan , M. S. A. Alam Khan , Daniel Wyler

We consider $B^{\pm,0} \to \rho^0(\omega)h^{\pm,0}$, where $\rho^0(\omega)$ decays to $\pi^+\pi^-$ and $h$ is any hadronic final state, such as $\pi$ or $K$. We find a large direct CP asymmetry in B-meson decays via $\rho \omega$…

High Energy Physics - Phenomenology · Physics 2016-11-03 Ryoji Enomoto , Masaharu Tanabashi

Even today, the convergence of the decay widths and some of the Dalitz plot parameters of the $\eta $$\,\rightarrow $$3\pi$ decays seems problematic in low energy QCD. We provide an overview of the current experimental and theoretical…

High Energy Physics - Phenomenology · Physics 2016-09-12 Marian Kolesar , Jiri Novotny

We present a calculation of the $\eta$-$\eta'$ mixing in the framework of large-$N_c$ chiral perturbation theory. A general expression for the $\eta$-$\eta'$ mixing at next-to-next-to-leading order (NNLO) is derived, including…

High Energy Physics - Phenomenology · Physics 2017-04-05 P. Bickert , P. Masjuan , S. Scherer

Chiral perturbation theory is the low energy effective theory of the strong interactions for the light pseudoscalar degrees of freedom. This program is based on effective Lagrangian techniques and is an expansion in the powers of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Ananthanarayan

We study how to probe the anomalous CP-violating couplings of top quark with photon, Z and gluon in the ttbar threshold region at future e+e- colliders. These couplings contribute to the difference of the t and tbar polarization vectors…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Jezabek , T. Nagano , Y. Sumino