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Related papers: Anomalous pion decay revisited

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The existence of a CPT anomaly is established for a particular four-dimensional Abelian lattice gauge theory with Ginsparg-Wilson fermions.

High Energy Physics - Theory · Physics 2010-04-05 F. R. Klinkhamer , J. Schimmel

We calculate all contributions $\propto T_F$ to the polarized three-loop anomalous dimensions in the M-scheme using massive operator matrix elements and compare to results in the literature. This includes the complete anomalous dimensions…

High Energy Physics - Phenomenology · Physics 2019-09-25 A. Behring , J. Blümlein , A. De Freitas , A. Goedicke , S. Klein , A. von Manteuffel , C. Schneider , K. Schönwald

In this article we review classical and recent results in anomalous diffusion and provide mechanisms useful for the study of the fundamentals of certain processes, mainly in condensed matter physics, chemistry and biology. Emphasis will be…

Statistical Mechanics · Physics 2019-02-25 Fernando A. Oliveira , Rogelma M. S. Ferreira , Luciano C. Lapas , Mendeli H. Vainstein

The vector form factor of the decay $\pi^{+} \rightarrow \gamma + e^{+} + \nu_e$ is calculated by the method for the pseudovector pion-nucleon system. The non-perturbative term is taken into account by using the parameter for the…

High Energy Physics - Phenomenology · Physics 2025-06-04 Susumu Kinpara

We perform a lattice QCD calculation of the \pi^0\to\gamma\gamma transition form factor and the associated decay width. We use a Euclidean time integral of the relevant three-point function to compute the decay amplitude for two-photon…

High Energy Physics - Lattice · Physics 2012-11-13 Xu Feng , Sinya Aoki , Hidenori Fukaya , Shoji Hashimoto , Takashi Kaneko , Jun-ichi Noaki , Eigo Shintani

Critical exponents are computed for a variety of twist-2 composite operators, which occur in polarized and unpolarized deep inelastic scattering, at leading order in the 1/N_f expansion. The resulting d-dimensional expressions, which depend…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. A. Gracey

Two program packages are presented for evaluating one-loop amplitudes. They can work either in dimensional regularization or in constrained differential renormalization. The latter method is found at the one-loop level to be equivalent to…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Hahn , M. Perez-Victoria

This study seeks a better comprehension of anomalies by exploring (n+1)-point perturbative amplitudes in a 2n-dimensional framework. The involved structures combine axial and vector vertices into odd tensors. This configuration enables…

High Energy Physics - Theory · Physics 2024-02-09 José Fernando Thuorst , Luciana Ebani , Thalis José Girardi

We introduce isospin breaking terms as well as (SU(3)) breaking terms to the anomalous (VVP) coupling in the hidden local symmetry scheme without affecting the low energy theorem on the processes such as (\pi\to 2 \gamma) and (\gamma\to…

High Energy Physics - Phenomenology · Physics 2009-10-28 Michio Hashimoto

We calculate the branching ratios of the yet unmeasured eta' decays into four pions, based on a combination of chiral perturbation theory and vector-meson dominance. The decays eta' --> 2(pi+ pi-) and eta' --> pi+ pi- 2pi0 are P-wave…

High Energy Physics - Phenomenology · Physics 2012-01-16 Feng-Kun Guo , Bastian Kubis , Andreas Wirzba

The rapidity anomalous dimension controls the scaling of transverse momentum dependent observables in the Sudakov region. In a conformal theory it is equivalent to the soft anomalous dimension, but in QCD this relation is broken by…

High Energy Physics - Phenomenology · Physics 2022-09-14 Ian Moult , Hua Xing Zhu , Yu Jiao Zhu

The transverse axial vector and vector anomalies in four-dimensional U(1) gauge theories studied in [10] is reexamined by means of perturbative methods. The absence of transverse anomalies for both axial vector and vector current is…

High Energy Physics - Phenomenology · Physics 2014-11-17 Wei-Min Sun , Hong-Shi Zong , Xiang-Song Chen , Fan Wang

Symmetries affected by the anomaly do not survive quantization and cannot be understood classically. They are of fundamental importance and offer an opportunity of expanding the theoretical framework. We examine the theory of the anomalous…

High Energy Physics - Phenomenology · Physics 2007-05-23 Olof Strandberg

We analyze the role played by anomaly poles in an anomalous gauge theory by discussing their signature in the corresponding off-shell effective action. The origin of these contributions, in the most general kinematical case, is elucidated…

High Energy Physics - Phenomenology · Physics 2009-12-15 Roberta Armillis , Claudio Coriano , Luigi Delle Rose , Marco Guzzi

We present the first part of a systematic calculation of the two-loop anomalous dimensions in the low-energy effective field theory (LEFT): the effects at dimension five in the power counting. Our calculation is performed in a basis with…

High Energy Physics - Phenomenology · Physics 2025-06-18 Luca Naterop , Peter Stoffer

The anomaly implies an obstruction to a fully chiral covariant calculation of the effective action in the abnormal parity sector of chiral theories. The standard approach then is to reconstruct the anomalous effective action from its…

High Energy Physics - Theory · Physics 2009-03-24 L. L. Salcedo

Anomalous quark triangles with one axial and two vector currents are studied in special kinematics when one of the vector currents carries a soft momentum. According to the Adler-Bardeen theorem the anomalous longitudinal part of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Arkady Vainshtein

A recent proposal suggests that even if a Ginsparg-Wilson lattice Dirac operator does not possess any topological zero modes in topologically-nontrivial gauge backgrounds, it can reproduce correct axial anomaly for sufficiently smooth gauge…

High Energy Physics - Lattice · Physics 2011-02-16 Ting-Wai Chiu , Tung-Han Hsieh

Dimensional regularization of Euclidean momentum space integrals is a highly successful technique in renormalization of quantum field theories. While it yields a straightforward algorithmic method, with which to evaluate diagrams beyond…

Mathematical Physics · Physics 2020-09-03 Juuso Österman

The anomalous pseudoscalar-photon vertex is studied in real time in and out of equilibrium in a constituent quark model. The goal is to understand the in-medium modifications of this vertex, exploring the possibility of enhanced isospin…

High Energy Physics - Phenomenology · Physics 2011-04-15 S. Prem Kumar , Daniel Boyanovsky , Hector J. de Vega , Richard Holman