?a1 Transitions and low-energy limit in the linear sigma model

A procedure for implementation of the generating equations in the linear sigma model of low energy QCD is presented. For any explicit symmetry breaking term, this procedure computes the masses of scalar and pseudoscalar mesons as well as various three-point and four-point interaction vertices that are needed in calculation of different decay widths and scattering amplitudes.

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Non-Abelian moduli on domain walls

International Journal of Modern Physics A ◽

10.1142/s0217751x14501930 ◽

2014 ◽

Vol 29 (32) ◽

pp. 1450193 ◽

Cited By ~ 5

Author(s):

E. Kurianovych ◽

M. Shifman

Keyword(s):

Sigma Model ◽

Domain Walls ◽

Cosmic Strings ◽

Equations Of Motion ◽

Orbit Interaction ◽

Low Energy ◽

Spin Orbit ◽

Energy Limit ◽

Wall Profile ◽

Bulk Parameters

We study a simple model supporting domain walls which possess two orientational moduli in addition to the conventional translational modulus. This model is conceptually close to Witten's cosmic strings. We observe an O(3) sigma model on the wall worldvolume in the low-energy limit. We solve (numerically) classical static equations of motion and find the wall profile functions and the value of the coupling of the O(3) model in terms of the bulk parameters. In the second part a term describing a spin-orbit interaction in the bulk is added, which gives rise to an entanglement between rotational and translational moduli. The corresponding extra term in the low-energy Lagrangian is calculated.

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Localization of the gauged linear sigma model for KK5-branes

Progress of Theoretical and Experimental Physics ◽

10.1093/ptep/ptab031 ◽

2021 ◽

Vol 2021 (3) ◽

Author(s):

Yuki Hiraga ◽

Yuki Sato

Keyword(s):

Partition Function ◽

Sigma Model ◽

Low Energy ◽

Target Space ◽

Linear Sigma Model ◽

Effective Theory ◽

Coulomb Branch ◽

World Sheet ◽

The World ◽

Gauged Linear Sigma Model

Abstract We study quantum aspects of the target space of the non-linear sigma model, which is a low-energy effective theory of the gauged linear sigma model (GLSM). As such, we especially compute the exact sphere partition function of the GLSM for KK$5$-branes whose background geometry is a Taub–NUT space, using the supersymmetric localization technique on the Coulomb branch. From the sphere partition function, we distill the world-sheet instanton effects. In particular, we show that, concerning the single-centered Taub–NUT space, instanton contributions exist only if the asymptotic radius of the $S^1$ fiber in the Taub–NUT space is zero.

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THE EFFECTIVE LAGRANGIAN OF THREE DIMENSIONAL QUANTUM CHROMODYNAMICS

International Journal of Modern Physics A ◽

10.1142/s0217751x92003616 ◽

1992 ◽

Vol 07 (32) ◽

pp. 7989-8000 ◽

Cited By ~ 9

Author(s):

G. FERRETTI ◽

S.G. RAJEEV ◽

Z. YANG

Keyword(s):

Quantum Chromodynamics ◽

Sigma Model ◽

Three Dimensional ◽

Low Energy ◽

Nonlinear Sigma Model ◽

Flavor Symmetry ◽

Energy Limit ◽

Long Wavelength ◽

Effective Lagrangian ◽

Chern Simons

We consider the low energy limit of three dimensional quantum chromodynamics (QCD) with an even number of flavors. We show that parity is not spontaneously broken, but the global (flavor) symmetry is spontaneously broken. The low energy effective Lagrangian is a nonlinear sigma model on the Grassmannian. Some Chern-Simons terms are necessary in the Lagrangian to realize the discrete symmetries correctly. We consider also another parametrization of the low energy sector which leads to a three dimensional analogue of the Wess-Zumino-Witten-Novikov model. Since three dimensional QCD is believed to be a model for quantum antiferromagnetism, our effective Lagrangian can describe their long wavelength excitations (spin waves).

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Finite density $O(3)$ non-linear sigma model and low energy physics

10.22323/1.251.0210 ◽

2016 ◽

Author(s):

Thomas Kloiber ◽

Falk Bruckmann ◽

Christof Gattringer ◽

Tin Sulejmanpasic

Keyword(s):

Sigma Model ◽

Low Energy ◽

Linear Sigma Model ◽

Finite Density ◽

Non Linear ◽

Energy Physics

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Chiral Perturbation Theory vs. Linear Sigma Model in A Chiral Imbalance Medium

10.20944/preprints201912.0221.v1 ◽

2019 ◽

Author(s):

Alexander Andrianov ◽

Vladimir Andrianov ◽

Domenec Espriu

Keyword(s):

Perturbation Theory ◽

Chiral Perturbation Theory ◽

Sigma Model ◽

Decay Constant ◽

Charged Pion ◽

Low Energy ◽

Linear Sigma Model ◽

Chiral Perturbation ◽

Energy Constants ◽

Parity Breaking

We compare Chiral Perturbation Theory (ChPT) and the Linear Sigma Model (LSM) as realizations of low energy QCD for light mesons in a chirally imbalanced medium. The relations between the low-energy constants of the Chiral Lagrangian and the corresponding constants of the Linear Sigma Model are established as well as the expressions for the decay constant of $\pi $-meson in the medium and for the mass of the $a_0$. In the large $N_c$ count taken from QCD the correspondence of ChPT and LSM is remarkably good and give a solid ground for search of chiral imbalance manifestation in pion physics. A possible experimental detection of chiral imbalance (and therefore a phase with Local Parity Breaking) is outlined in the charged pion decays inside the fireball.

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Chiral Perturbation Theory vs. Linear Sigma Model in a Chiral Imbalance Medium

Particles ◽

10.3390/particles3010002 ◽

2020 ◽

Vol 3 (1) ◽

pp. 15-22 ◽

Cited By ~ 1

Author(s):

Alexander Andrianov ◽

Vladimir Andrianov ◽

Domenec Espriu

Keyword(s):

Perturbation Theory ◽

Chiral Perturbation Theory ◽

Sigma Model ◽

Decay Constant ◽

Low Energy ◽

Linear Sigma Model ◽

Chiral Perturbation ◽

Large N ◽

Energy Quantum ◽

Energy Constants

We compare the chiral perturbation theory (ChPT) and the linear sigma model (LSM) as realizations of low energy quantum chromodynamics (QCD) for light mesons in a chirally-imbalanced medium. The relations between the low-energy constants of the chiral Lagrangian and the corresponding constants of the linear sigma model are established as well as the expressions for the decay constant of π -meson in the medium and for the mass of the a 0 . In the large N c count taken from QCD the correspondence of ChPT and LSM is remarkably good and provides a solid ground for the search of chiral imbalance manifestations in pion physics. A possible experimental detection of chiral imbalance (and therefore a phase with local parity breaking) is outlined in the charged pion decays inside the fireball.

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Two-body decay widths of lowest lying and next-to-lowest lying scalar and pseudoscalar mesons in generalized linear sigma model

International Journal of Modern Physics A ◽

10.1142/s0217751x15501341 ◽

2015 ◽

Vol 30 (22) ◽

pp. 1550134 ◽

Cited By ~ 2

Author(s):

S. Mohammad Zebarjad ◽

Soodeh Zarepour

Keyword(s):

Energy Region ◽

Sigma Model ◽

Low Energy ◽

Experimental Results ◽

Linear Sigma Model ◽

Pseudoscalar Mesons ◽

Decay Widths

Two-body decay widths of lowest lying and next-to-lowest lying scalar and pseudoscalar mesons are studied in generalized linear sigma model (GLSM) of low-energy QCD. This model which considers mixing between “two-quark” and “four-quark” chiral nonets has been employed to investigate various decays and scatterings in low-energy region of QCD. In this paper, [Formula: see text] and [Formula: see text] are obtained and it is shown that two-body decay widths of lowest lying mesons are well predicted by this model while for the next-to-lowest lying mesons, only some of the decay widths agree with the experimental results. We have compared the predicted decay widths in GLSM with the results obtained in single nonet linear sigma model (SNLSM) to indicate that chiral nonet mixing greatly improves the predictions of SNLSM for decay widths.

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