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Related papers: Cornering Large-$N_c$ QCD with Positivity Bounds

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We study Quantum Chromodynamics in the chiral large $N_c$ limit which contains a left-handed Weyl fermion in the fundamental representation, a left-handed Weyl fermion in the two index antisymmetric representation and $(N_c-3)$ left-handed…

High Energy Physics - Phenomenology · Physics 2024-04-22 Axel Halgaard Kristensen , Thomas A. Ryttov

Using QCD sum rules with nonlocal condensates, we show that the distribution amplitude of the longitudinally polarized $\rho$-meson may have a shorttailed platykurtic profile in close analogy to our recently proposed platykurtic…

High Energy Physics - Phenomenology · Physics 2016-10-28 N. G. Stefanis , A. V. Pimikov

The QCD-coupling is a necessary input in the computation of many observables, and the parametric error on input parameters can be a dominant source of uncertainty. The coupling can be extracted by comparing high order perturbative…

High Energy Physics - Lattice · Physics 2022-03-16 Leonardo Chimirri , Rainer Sommer

We present new non-perturbative results about the meson spectrum and the low-energy constants of QCD in the 't Hooft large-$N$ limit, $N\to\infty$ with $N_{\scriptscriptstyle{\rm f}}/N\to 0$. These are obtained from lattice Monte Carlo…

High Energy Physics - Lattice · Physics 2026-03-03 Claudio Bonanno , Margarita García Pérez , Antonio González-Arroyo , Ken-Ichi Ishikawa , Masanori Okawa

Quark-hadron duality implies that a process described in terms of quark loops should be the hadronic amplitude when averaged over a sufficient number of states. Ambiguities associated with the notion of quark hadron duality can be made…

High Energy Physics - Theory · Physics 2008-11-26 Thomas D. Cohen , Elizabeth S. Werbos

Superconformal algebra leads to remarkable connections between the masses of mesons and baryons of the same parity -- supersymmetric relations between the bosonic and fermionic bound states of QCD. Supercharges connect the mesonic…

High Energy Physics - Phenomenology · Physics 2016-08-03 Stanley J. Brodsky , Guy F. de Téramond , Hans Günter Dosch , Cédric Lorcé

Based on the self-consistent scheme beyond mean-field approximation in the large $N_c$ expansion, including current quark mass explicitly, a general scheme of SU(2) NJL model is developed. To ensure the quark self-energy expanded in the…

High Energy Physics - Phenomenology · Physics 2018-01-17 Mei Huang , Pengfei Zhuang , Weiqin Chao

The interactions of $\rho$, $K^*$, $\phi$ and $\omega$ vector-mesons with low-momentum $\pi$, $K$ and $\eta$ pseudoscalar mesons are constrained by chiral symmetry. We derive a heavy vector-meson chiral Lagrangian in which the vector mesons…

High Energy Physics - Phenomenology · Physics 2008-11-26 Elizabeth Jenkins , Aneesh V. Manohar , Mark B. Wise

In this exploratory lattice study, low-energy scattering of the $(D\bar{D}^{*})^\pm$ meson system is analyzed using lattice QCD with $N_f=2$ twisted mass fermion configurations with three pion mass values. The calculation is performed…

A soft-wall anti-de Sitter/QCD model with a modified five-dimensional metric at the infrared region is constructed to obtain a nontrivial dilaton solution, which incorporates the chiral symmetry breaking and linear confinement. By taking…

High Energy Physics - Phenomenology · Physics 2010-01-28 Yan-Qin Sui , Yue-Liang Wu , Zhi-Feng Xie , Yi-Bo Yang

In this talk we briefly review how the unitarization of Chiral Perturbation Theory with dispersion relations can successfully describe the meson-meson scattering data and generate light resonances, whose mass, width and nature can be…

High Energy Physics - Phenomenology · Physics 2015-05-18 Jose R. Pelaez , C. Hanhart , J. Nebreda , G. Rios

Numerical simulations of QCD-like theories in which the number of flavors is adjusted so that the beta function is very small, but confinement and chiral symmetry breaking nevertheless take place, appear to reveal the presence of a…

High Energy Physics - Phenomenology · Physics 2016-09-14 Maarten Golterman , Yigal Shamir

We present the first direct determination of meson-baryon resonance parameters from a scattering amplitude calculated using lattice QCD. In particular, we calculate the elastic $I=3/2$, $p$-wave nucleon-pion amplitude on a single ensemble…

High Energy Physics - Lattice · Physics 2018-02-13 Christian Walther Andersen , John Bulava , Ben Hörz , Colin Morningstar

The electromagnetic form factor of the pion is obtained using a particular realization of QCD in the large $N_c$ limit, which sums up the infinite number of zero-width resonances to yield an Euler's Beta function of the Veneziano type. This…

High Energy Physics - Phenomenology · Physics 2009-11-07 C. A. Dominguez

In a theory with linear confinement, such as QCD, the masses squared m^2 of mesons with high spin S or high radial excitation number n are expected, from semiclassical arguments, to grow linearly with S and n. We show that this behavior can…

High Energy Physics - Phenomenology · Physics 2008-11-26 Andreas Karch , Emanuel Katz , Dam T. Son , Mikhail A. Stephanov

We present results of meson and baryon spectroscopy using the Chirally Improved Dirac operator on lattices of size 16**3 x 32 with two mass-degenerate light sea quarks. Three ensembles with pion masses of 322(5), 470(4) and 525(7) MeV and…

High Energy Physics - Lattice · Physics 2015-03-17 Georg P. Engel , C. B. Lang , Markus Limmer , Daniel Mohler , Andreas Schäfer

Multiple-quantum coherence (MQC) spectroscopy is a powerful technique for probing spin clusters, offering insights into diverse materials and quantum many-body systems. However, prior experiments have revealed a rapid decay in MQC…

Quantum Physics · Physics 2024-12-13 Christian Bengs , Chongwei Zhang , Ashok Ajoy

Holographic QCD provides a unique framework in which to compute QCD observables. In this talk we summarize recent numerical work on computing the pion electromagnetic form factor using an AdS/QCD action that includes both spontaneous and…

High Energy Physics - Phenomenology · Physics 2017-08-23 Herry J. Kwee , Richard F. Lebed

Removal of the quenched approximation in the mechanism which produced an analytic estimate of quark-binding potentials, along with a reasonable conjecture of the color structure of the nucleon formed by such a binding potential, is shown to…

High Energy Physics - Phenomenology · Physics 2015-01-20 H. M. Fried , Y. Gabellini , T. Grandou , Y. -M. Sheu

Rather than regarding the restriction of current lattice QCD simulations to quark masses that are 5--10 times larger than those observed, we note that this presents a wonderful opportunity to deepen our understanding of QCD. Just as it has…

Nuclear Theory · Physics 2010-05-28 W. Detmold , D. B. Leinweber , W. Melnitchouk , A. W. Thomas , S. V. Wright