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Related papers: New results with colour-sextet quarks

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We consider how tetraquarks can affect the chiral phase transition in theories like QCD, with light quarks coupled to three colors. For two flavors the tetraquark field is an isosinglet, and its effect is minimal. For three flavors,…

High Energy Physics - Phenomenology · Physics 2016-09-14 Robert D. Pisarski , Vladimir V. Skokov

We argue that the order of the chiral transition for N_f=2 is a sensitive probe of the QCD vacuum, in particular of the mechanism of color confinement. A strategy is developed to investigate the order of the transition by use of finite size…

High Energy Physics - Lattice · Physics 2009-11-11 M. D'Elia , A. Di Giacomo , C. Pica

QCD with three degenerate quark flavours at zero baryon density exhibits a first order thermal phase transition for small quark masses, which changes to a smooth crossover for some critical quark mass m^c_0, i.e. the chiral critical point.…

High Energy Physics - Lattice · Physics 2008-11-26 Philippe de Forcrand , Owe Philipsen

We determine the chiral phase transition line in (2+1)-flavor QCD for small values of the light quark chemical potential. We show that for small values of the chemical potential the curvature of the phase transition line can be deduced from…

High Energy Physics - Lattice · Physics 2011-02-01 O. Kaczmarek , F. Karsch , E. Laermann , C. Miao , S. Mukherjee , P. Petreczky , C. Schmidt , W. Soeldner , W. Unger

We present results on the chiral and deconfinement properties of the QCD transition at finite temperature. Calculations are performed with 2+1 flavors of quarks using the p4, asqtad and HISQ/tree actions. Lattices with temporal extent…

We study the finite-temperature phase structure and the transition temperature of QCD with two flavors of dynamical quarks on a lattice with the temporal size $N_t=4$, using a renormalization group improved gauge action and the Wilson quark…

We study Quantum Chromodynamics with eight flavours by use of lattice simulations and present evidence that the theory still breaks chiral symmetry in the zero temperature, continuum limit. This confirms that the lower end of the conformal…

High Energy Physics - Lattice · Physics 2008-12-18 Albert Deuzeman , Maria Paola Lombardo , Elisabetta Pallante

Suggested holographic duals of QCD, based on AdS/CFT duality, predict that one should be able to vary the scales of colour confinement and chiral-symmetry breaking independently. Furthermore they suggest that such independent variation of…

High Energy Physics - Lattice · Physics 2008-11-26 D. K. Sinclair

The family of SU(2) theories with matter transforming in the adjoint representation has attracted interest from many angles. The two-flavour theory, known as Minimal Walking Technicolor, has a body of evidence pointing to it being in the…

High Energy Physics - Lattice · Physics 2024-10-28 Ed Bennett , Andreas Athenodorou , Georg Bergner , Pietro Butti , Biagio Lucini

Chiral perturbation theory in the two-flavour sector allows one to analyse Green functions in QCD in a limit where the strange quark mass is considered to be large in comparison to the external momenta and to the light quark masses. In this…

High Energy Physics - Phenomenology · Physics 2009-07-28 Juerg Gasser , Christoph Haefeli , Mikhail A. Ivanov , Martin Schmid

We study the chiral phase transition with 2 + 1 quark flavors in an improved soft-wall AdS/QCD model, which can produce the light meson spectrum and many other low-energy quantities consistent with experiments in the two-flavor case. The…

High Energy Physics - Phenomenology · Physics 2018-12-12 Zhen Fang , Yue-Liang Wu , Lin Zhang

We study the evolution of the coupling in SU(2) gauge field theory with $N_f=4$, 6 and 10 fundamental fermion flavours on the lattice. These values are chosen close to the expected edges of the conformal window, where the theory possesses…

High Energy Physics - Lattice · Physics 2015-03-19 Tuomas Karavirta , Jarno Rantaharju , Kari Rummukainen , Kimmo Tuominen

Multi-flavour (N_f>=3) Chiral Perturbation Theory (ChPT) may exhibit instabilities due to vacuum fluctuations of sea q-bar q pairs. Keeping the fluctuations small would require a very precise fine-tuning of the low-energy constants L_4 and…

High Energy Physics - Phenomenology · Physics 2016-09-06 S. Descotes-Genon , L. Girlanda , J. Stern

We investigate the properties of quark matter at finite density and temperature using the nonlinear chiral extension of Colour Dielectric Model (CCM). Assuming that the square of the meson fields devlop non- zero vacuum expectation value,…

Nuclear Theory · Physics 2008-11-26 Sanjay K. Ghosh , S. C. Phatak

The (light but not-so-light) strange quark may play a special role in the low-energy dynamics of QCD. The presence of strange quark pairs in the sea may have a significant impact of the pattern of chiral symmetry breaking : in particular…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Descotes-Genon

The electroweak gauge symmetry is allowed to be spontaneously broken by the strongly interacting vector-like gauge dynamics. When the gauge coupling of a theory runs slowly in a wide range of energy scale, the theory is a candidate for…

High Energy Physics - Lattice · Physics 2010-03-18 N. Yamada , M. Hayakawa , K. -I. Ishikawa , Y. Osaki , S. Takeda , S. Uno

Recently we have made considerable progress in our understanding of the behavior of QCD in extreme conditions of high temperature or large baryon number density. Among the highlights are the prediction of a well-characterized true critical…

High Energy Physics - Phenomenology · Physics 2007-05-23 Frank Wilczek

We study the deconfinement transition in two-flavour lattice QCD with dynamical overlap fermions. Our simulations have been carried out on a $16^3 \times 6$ lattice at a pion mass around 500 MeV with a special HMC algorithm without any…

High Energy Physics - Lattice · Physics 2015-02-11 O. A. Kochetkov , V. G. Bornyakov , P. V. Buividovich , N. Cundy

The finite temperature transition of QCD with two degenerate light quarks is studied on the lattice with a renormalization group improved gauge action and the Wilson quark action. We have made simulations on an $8^3\times 4$ lattice near…

High Energy Physics - Lattice · Physics 2009-10-28 Y. Iwasaki , K. Kanaya , S. Kaya , T. Yoshie

We investigate chiral and deconfinement transitions in the framework of the strong coupling lattice QCD for color SU(3) with one species of unrooted staggered fermion at finite temperature and quark chemical potential. We take account of…

High Energy Physics - Lattice · Physics 2011-02-28 Takashi Z. Nakano , Kohtaroh Miura , Akira Ohnishi