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Related papers: Loop Calculations and OZI Rule

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In this paper, by employing the $k_{T}$ factorization theorem, we made the first calculation for the space-like scalar pion form factor $Q^2 F(Q^2)$ at the leading order (LO) and the next-to-leading order (NLO) level, and then found the…

High Energy Physics - Phenomenology · Physics 2015-05-20 Shan Cheng , Ya-Lan Zhang , Zhen-Jun Xiao

We investigate the reactions p n -> d omega and p n -> d phi close to the corresponding thresholds. The S-wave amplitudes are calculated within the framework of the two-step model which is described by a triangle graph with pi, rho and…

Nuclear Theory · Physics 2007-05-23 V. Yu. Grishina , L. A. Kondratyuk , M. Büscher

We study the possibility to constrain the hidden strangeness content of the nucleon by means of the polarization observables in phi meson electroproduction. We consider the OZI evading direct knockout mechanism that arises from the…

Nuclear Theory · Physics 2009-10-31 Yongseok Oh , Alexander I. Titov , Shin Nan Yang , Toshiyuki Morii

A complete calculation of the pion-nucleon loops that contribute to the transition operator for $NN\to NN\pi$ up-to-and-including next-to-next-to-leading order (N$^2$LO) in chiral effective field theory near threshold is presented. The…

Nuclear Theory · Physics 2013-05-30 A. A. Filin , V. Baru , E. Epelbaum , C. Hanhart , H. Krebs , A. E. Kudryavtsev , F. Myhrer

Gate elimination is the primary technique for proving explicit lower bounds against general Boolean circuits, including Li and Yang's state-of-the-art $3.1n - o(n)$ bound for affine dispersers (STOC 2022). Every circuit lower bound is…

Computational Complexity · Computer Science 2026-04-28 Marco Carmosino , Ngu Dang , Tim Jackman

I calculate the leading logarithmic contributions up to two-loop order of the octet part of the K -> pi pi amplitude. This sector of the weak chiral Lagrangian is believed to be the main source of the enhancement of the I=0 relative to the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Matthias Buchler

Recently, the BES collaboration has published an extensive partial wave analysis of experimental data on J/psi -> phi pi+pi-, J/psi -> omega pi+pi-, J/psi -> phi K+K- and J/psi -> omega K+K-. These new results are analyzed here, with full…

High Energy Physics - Phenomenology · Physics 2008-11-26 Timo A. Lähde , Ulf-G. Meißner

In this paper, by employing the $k_{T}$ factorization theorem, we calculate firstly the next-to-leading-order (NLO) twist-3 contributions to the pion electromagnetic form factors in the $\pi\gamma^* \to \pi$ process. From the analytical and…

High Energy Physics - Phenomenology · Physics 2014-03-26 Shan Cheng , Ying-Ying Fan , Zhen-Jun Xiao

We study antiproton-proton annihilation at rest into $\pi\phi$ and $\gamma\phi$. Rescattering by $\overline{K^*}K+K^*\overline{K}$ and $\rho^{+}\rho^{-}$ for $\overline{p}p\rightarrow\pi\phi$ states is sizable, of order $(0.90\, {\rm…

Nuclear Theory · Physics 2015-06-26 M. P. Locher , Y. Lu , B. S. Zou

NLO QCD corrections to the process $pp \rightarrow e^+\nu_e \mu^- \bar{\nu}_{\mu} \tau^+\tau^- b \bar{b}+X$ are presented with the full off-shell effects included. The calculation includes all resonant and non-resonant Feynman diagrams,…

High Energy Physics - Phenomenology · Physics 2022-12-06 Jasmina Nasufi

We investigate the decay $\phi\to\pi^+\pi^-\pi^0$ in an effective-Lagrangian framework that keeps the dominant $\rho\pi$ mechanism and the direct three-pion term explicitly separated at the amplitude level. The resonant contribution is…

High Energy Physics - Phenomenology · Physics 2026-04-21 Seung-il Nam , Jung Keun Ahn

We study the self-energy amplitudes for the rho-omega meson system produced by an effective field theory model at the quark level characterized by a finite range quark-quark interaction and an isospin breaking bare quark mass difference…

Nuclear Theory · Physics 2008-11-26 K. L. Mitchell , P. C. Tandy

We show that the long known puzzling branching ratios of open-charm decays in electron-positron annihilation can be reasonably described with a simple form factor, which strongly suppresses open channels far above threshold. Application to…

High Energy Physics - Phenomenology · Physics 2009-08-03 Eef van Beveren , George Rupp

The final state interaction (FSI) contribution to charged $D$ decay into $K\pi\pi$ is computed within a light-front framework, considering $S$-wave $K\pi$ interactions in $1/2$ and $3/2$ isospin states. The convergence of the rescattering…

High Energy Physics - Phenomenology · Physics 2014-07-04 T. Frederico , K. S. F. F. Guimarães , O. Lourenço , W. de Paula , I. Bediaga , A. C. dos Reis

The differential cross sections of $pD\to ^3He X$ reactions, where $X=\eta, \ \eta'\ ,\omega, \ \phi $, are calculated on the basis of a two-step mechanism involving the subprocesses $pp\to d\pi ^+$ and $\pi^+n\to Xp $. It is shown that…

Nuclear Theory · Physics 2008-02-03 L. A. Kondratyuk , Yu. N. Uzikov

We present the ingredients necessary for the determination of physical K->pi pi decay amplitudes for Delta I=3/2 transitions, from lattice simulations at unphysical kinematics and the use of chiral perturbation theory at next-to-leading…

High Energy Physics - Lattice · Physics 2008-11-26 C. -J. D. Lin , G. Martinelli , E. Pallante , C. T. Sachrajda , G. Villadoro

We present technical details of the evaluation of the elastic pi-pi scattering amplitude to two loops in chiral perturbation theory. In particular, we elaborate on the renormalization procedure at the two-loop order and on the evaluation of…

High Energy Physics - Phenomenology · Physics 2009-10-30 J. Bijnens , G. Colangelo , G. Ecker , J. Gasser , M. E. Sainio

Based on the effective Lagrangian approach, the $ J/\psi \to p \bar{p} \phi$ decay is studied in an isobar resonance model with the assumption that the $\phi$-meson is produced from intermediate nucleon resonances. The contributions from…

Nuclear Theory · Physics 2013-05-30 Jian-ping Dai , Peng-nian Shen , Ju-jun Xie , Bing-song Zou

We explore the important task of applying a phase $\exp(i\,f(x))$ to a computational basis state $\left| x \right>$. The closely related task of rotating a target qubit by an angle depending on $f(x)$ is also studied. Such operations are…

In this work, we study the isospin-violating decay of $\phi\to \omega\pi^0$ and quantify the electromagnetic (EM) transitions and intermediate meson exchanges as two major sources of the decay mechanisms. In the EM decays, the present datum…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gang Li , Qiang Zhao , Bing-Song Zou