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Related papers: Scrutinizing the pion condensed phase

200 papers

We analyze the effect of an isospin chemical potential \mu_I in the Sakai-Sugimoto model, which is the string dual of a confining gauge theory related to large N_c QCD, at temperatures below the chiral symmetry restoration temperature. For…

High Energy Physics - Theory · Physics 2009-09-29 Ofer Aharony , Kasper Peeters , Jacob Sonnenschein , Marija Zamaklar

Broken chiral symmetry has become the basis for a unified treatment of hadronic interactions at low energies. After reviewing mechanisms for spontaneous chiral symmetry breaking, I outline the construction of the low--energy effective field…

High Energy Physics - Phenomenology · Physics 2009-10-31 Gerhard Ecker

For the first time, elastic pion-nucleon scattering is analyzed in the framework of chiral perturbation theory up to fourth order with explicit $\Delta$ degrees of freedom. The analysis is performed within the heavy-baryon expansion as well…

Nuclear Theory · Physics 2020-01-15 Dmitrij Siemens

Studies of the QCD phase diagram must properly include nucleonic degrees of freedom and their thermodynamics in the range of baryon chemical potentials characteristic of nuclear matter. A useful framework for incorporating relevant nuclear…

High Energy Physics - Phenomenology · Physics 2014-01-27 Matthias Drews , Thomas Hell , Bertram Klein , Wolfram Weise

Starting from a relativistic formulation of the pion-nucleon-delta system, the most general structure of 1/M corrections for a heavy baryon chiral lagrangian including spin 3/2 resonances is given. The heavy components of relativistic…

High Energy Physics - Phenomenology · Physics 2009-10-28 Thomas R. Hemmert , Barry R. Holstein , Joachim Kambor

We investigate the possible formation of a Bose-Einstein condensed phase of pions in the early Universe at nonvanishing values of lepton flavor asymmetries. A hadron resonance gas model with pion interactions, based on first-principle…

High Energy Physics - Phenomenology · Physics 2021-01-08 Volodymyr Vovchenko , Bastian B. Brandt , Francesca Cuteri , Gergely Endrődi , Fazlollah Hajkarim , Jürgen Schaffner-Bielich

We study the dynamics of the chiral phase transition expected during the expansion of the quark-gluon plasma produced in a high energy hadron or heavy ion collision, using the $O(4)$ linear sigma model in the mean field approximation.…

High Energy Physics - Phenomenology · Physics 2008-02-03 Yuval Kluger

We evaluate the isospin breaking corrections to the scattering amplitude \pi^- K^+ -> \pi^- K^+ at threshold in the framework of chiral perturbation theory. This channel is of particular interest for the strong 2S-2P energy level shift in…

High Energy Physics - Phenomenology · Physics 2009-11-07 Bastian Kubis , Ulf-G. Meißner

We determine the possible trajectories the universe may have followed in the QCD phase diagram during the QCD epoch. We focus on the roles of chiral symmetry breaking and pion condensation under high imbalances in lepton asymmetry. Adopting…

High Energy Physics - Phenomenology · Physics 2025-11-11 Osvaldo Ferreira , Eduardo S. Fraga , Maurício Hippert , Jürgen Schaffner-Bielich

We introduce a random matrix model with the symmetries of QCD with two colors at nonzero isospin and baryon chemical potentials and temperature. We analyze its phase diagram and find phases with condensation of pion and diquark states in…

High Energy Physics - Phenomenology · Physics 2009-11-10 B. Klein , D. Toublan , J. J. M. Verbaarschot

We construct a chiral Lagrangian containing besides the usual pion field (pi) also its first radial excitation (pi'). The Lagrangian is derived by bosonization of a Nambu--Jona-Lasinio quark model with separable non-local interactions, with…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. K. Volkov , C. Weiss

We apply the perturbative chiral quark model to give predictions for the electromagnetic O(p^2) low-energy couplings of the ChPT effective Lagrangian that define the electromagnetic mass shifts of nucleons and first-order (e^2) radiative…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. E. Lyubovitskij , Th. Gutsche , Amand Faessler , R. Vinh Mau

Recent progress in the description of the properties of hadronic atoms on the basis of non-relativistic effective Lagrangian approach and Chiral Perturbation Theory (ChPT) is reported. For the case of the pi(+)pi(-) atom decay, the problem…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Rusetsky

In this paper, we employ chiral effective field theory to study the process of electron-positron annihilation into four pions in the low energy region within $E_{c.m.}\leq 0.6$ GeV. The prediction of the cross section is obtained through…

High Energy Physics - Phenomenology · Physics 2026-05-19 Jia-Yu Zhou , Hao-Xiang Pan , Ling-Yun Dai

We study relativistic Bose-Einstein condensation at finite density and temperature using the linear sigma model in the one-particle-irreducible 1/N-expansion. We derive the effective potential to next-to-leading (NLO) order and show that it…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jens O. Andersen , Tomas Brauner

We evaluate the electric and magnetic polarizabilities of charged pions in the framework of chiral perturbation theory at next-to-leading order. This requires a two-loop evaluation of the Compton amplitude near threshold. We estimate the…

High Energy Physics - Phenomenology · Physics 2011-07-19 Urs Buergi

The formation of charged pion condensate under parallel electromagnetic fields is studied within the two-flavor Nambu--Jona-Lasinio model. The technique of Schwinger proper time method is extended to explore the quantity locating in the…

High Energy Physics - Phenomenology · Physics 2018-05-03 Jingyi Chao , Mei Huang , Andrey Radzhabov

We consider the chiral phase transition relevant for QCD matter at finite temperature but with vanishing baryon density. Presumably, the chiral phase transition is of second order for two-flavor QCD in the chiral limit. Near the transition…

High Energy Physics - Theory · Physics 2025-07-30 Yanyan Bu , Zexin Yang

In this talk we present investigation of the phase structure of a (1+1)-dimensional quark model with four-quark interaction and in the presence of baryon ($\mu_B$), isospin ($\mu_I$) and chiral isospin ($\mu_{I5}$) chemical potentials.…

High Energy Physics - Phenomenology · Physics 2018-08-16 T. G. Khunjua , V. C. Zhukovsky , K. G. Klimenko , R. N. Zhokhov

Soft-pion theorems are used to show how chiral symmetry constrains the contributions of low-momentum pions to the quark condensate, the pion decay constant and hadron masses, all of which have been proposed as signals of partial restoration…

Nuclear Theory · Physics 2007-05-23 Michael C. Birse