THE CHIRAL SUSCEPTIBILITY AROUND THE CRITICAL END POINT

This paper is devoted to locate the position of critical end point (CEP) and study its properties. The CEP for different current quark masses are located. It is found that as the current quark mass tends to zero, the position of the CEP tends to the tricrtical point (TCP), while the height of the chiral susceptibility tends to infinity faster and faster, which indicates that the transition from CEP to TCP is continuous. This continuity causes the so-called hidden TCP effect.

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STABILITY OF VACUUM AND QCD PHASE TRANSITION IN DYSON-SCHWINGER EQUATION APPROACH OF QCD

International Journal of Modern Physics E ◽

10.1142/s0218301308010945 ◽

2008 ◽

Vol 17 (09) ◽

pp. 1965-1978 ◽

Cited By ~ 1

Author(s):

YU-XIN LIU ◽

HUAN CHEN ◽

LEI CHANG ◽

YUE ZHAO ◽

WEI YUAN

Keyword(s):

Phase Transition ◽

Simple Model ◽

Quark Mass ◽

Equation Approach ◽

Qcd Phase Transition ◽

Current Quark Mass ◽

Running Coupling ◽

The Stability ◽

Chiral Susceptibility ◽

Current Quark

We describe briefly the effects of the running coupling strength, the current quark mass, the temperature and density on the QCD phase structure and its transition in the framework of Dyson-Schwinger equation approach of QCD. With a simple model, we show that the chiral susceptibility can identify the stability of the vacuum and plays an important role in describing the QCD Phase transition.

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Quarks in a Polar Model

10.20944/preprints201801.0143.v1 ◽

2018 ◽

Author(s):

Vladimir Salomatov

Keyword(s):

Helmholtz Equation ◽

Quark Mass ◽

Rest Mass ◽

Mass Determination ◽

Quark Masses ◽

Zero Function ◽

Current Quark Mass ◽

Neumann Function ◽

Polar Model ◽

Current Quark

Current-quark masses are compared to the rest masses allowed by the Helmholtz equation in a polar model. Within the uncertainty of the current u quark mass determination, the current quark mass coincides with the rest mass allowed by the Helmholtz equation in the polar model in accordance with the second root of the zero Neumann function. Current d quark mass coincides with the rest mass calculated in accordance with the third root of the Bessel zero function. On the basis of a comparison of these results with the results obtained earlier for ordinary real particles u and d quarks stability is discussed.

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Relations among constituent quark masses from Mv2-Mp2approximately=0.56 GeV2compared with current quark mass relations from PCAC

Journal of Physics G Nuclear and Particle Physics ◽

10.1088/0954-3899/18/4/009 ◽

1992 ◽

Vol 18 (4) ◽

pp. 739-743 ◽

Cited By ~ 1

Author(s):

S Chakrabarty ◽

S Deoghuria

Keyword(s):

Quark Mass ◽

Constituent Quark ◽

Quark Masses ◽

Current Quark Mass ◽

Current Quark

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Ratio of flavour non-singlet and singlet scalar density renormalisation parameters in $$N_\mathrm {f}=3$$ QCD with Wilson quarks

The European Physical Journal C ◽

10.1140/epjc/s10052-021-09387-z ◽

2021 ◽

Vol 81 (7) ◽

Author(s):

Jochen Heitger ◽

Fabian Joswig ◽

Pia L. J. Petrak ◽

Anastassios Vladikas

Keyword(s):

Quark Mass ◽

Tree Level ◽

Lattice Action ◽

Quark Masses ◽

Current Quark Mass ◽

Functional Boundary ◽

Normalisation Factor ◽

Functional Boundary Conditions ◽

Current Quark ◽

Wilson Fermions

AbstractWe determine non-perturbatively the normalisation factor $$r_{\mathrm{m}}\equiv Z_{\mathrm{S}}/Z_{\mathrm{S}}^{0}$$ r m ≡ Z S / Z S 0 , where $$Z_{\mathrm{S}}$$ Z S and $$Z_{\mathrm{S}}^{0}$$ Z S 0 are the renormalisation parameters of the flavour non-singlet and singlet scalar densities, respectively. This quantity is required in the computation of quark masses with Wilson fermions and for instance the renormalisation of nucleon matrix elements of scalar densities. Our calculation involves simulations of finite-volume lattice QCD with the tree-level Symanzik-improved gauge action, $$N_{\mathrm{f}}= 3$$ N f = 3 mass-degenerate $${\mathrm{O}}(a)$$ O ( a ) improved Wilson fermions and Schrödinger functional boundary conditions. The slope of the current quark mass, as a function of the subtracted Wilson quark mass is extracted both in a unitary setup (where nearly chiral valence and sea quark masses are degenerate) and in a non-unitary setup (where all valence flavours are chiral and the sea quark masses are small). These slopes are then combined with $$Z \equiv Z_{\mathrm{P}}/(Z_{\mathrm{S}}Z_{\mathrm{A}})$$ Z ≡ Z P / ( Z S Z A ) in order to obtain $$r_{\mathrm{m}}$$ r m . A novel chiral Ward identity is employed for the calculation of the normalisation factor Z. Our results cover the range of gauge couplings corresponding to lattice spacings below $$0.1\,$$ 0.1 fm, for which $$N_{\mathrm{f}}= 2+1$$ N f = 2 + 1 QCD simulations in large volumes with the same lattice action are typically performed.

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Wigner Solution to the Quark Gap Equation in the Nonzero Current Quark Mass

Chinese Physics Letters ◽

10.1088/0256-307x/29/4/041201 ◽

2012 ◽

Vol 29 (4) ◽

pp. 041201 ◽

Cited By ~ 4

Author(s):

Yu Jiang ◽

Hao Gong ◽

Wei-Min Sun ◽

Hong-Shi Zong

Keyword(s):

Quark Mass ◽

Gap Equation ◽

Current Quark Mass ◽

Current Quark

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SCALAR NONETS IN POLE-DOMINATED QCD SUM RULES

Modern Physics Letters A ◽

10.1142/s0217732308029083 ◽

2008 ◽

Vol 23 (27n30) ◽

pp. 2230-2233

Author(s):

TORU KOJO ◽

DAISUKE JIDO

Keyword(s):

Operator Product Expansion ◽

Quark Mass ◽

Sum Rules ◽

Operator Product ◽

Qcd Sum Rules ◽

Current Quark Mass ◽

Pole Dominance ◽

Light Scalar ◽

Current Quark

The light scalar nonets are studied using the QCD sum rules for the tetraquark operators. The operator product expansion for the correlators is calculated up to dimension 12 and this enables us to perform analyses retaining sufficient pole-dominance. To classify the light scalar nonets, we investigate the dependence on current quark mass and flavor dynamics. Especially, to examine the latter, we study separately SU(3) singlet and octet states, and show that the number of annihilation diagrams is largely responsible for their differences, which is also the case even after the inclusion of the finite quark mass. Our results support the tetraquark picture for isosinglets, while that for octets is not conclusive yet.

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ON THE QCD SUM RULE DETERMINATION OF THE STRANGE QUARK MASS

International Journal of Modern Physics A ◽

10.1142/s0217751x0100756x ◽

2001 ◽

Vol 16 (supp01b) ◽

pp. 588-590 ◽

Cited By ~ 1

Author(s):

NELLO PAVER

Keyword(s):

Spectral Function ◽

Quark Mass ◽

Strange Quark ◽

Sum Rules ◽

Sum Rule ◽

Strange Quark Mass ◽

Current Quark Mass ◽

Current Quark

I briefly review recent QCD Sum Rules determinations of the strange current quark mass, based on the analysis of the two-point ΔS=1 scalar correlators and discuss, in particular, the role of resonances and non-resonant background in the spectral function.

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Quasi-distribution amplitudes for pion and kaon via the nonlocal chiral-quark model

Modern Physics Letters A ◽

10.1142/s0217732317502182 ◽

2017 ◽

Vol 32 (39) ◽

pp. 1750218 ◽

Cited By ~ 13

Author(s):

Seung-il Nam

Keyword(s):

Quark Model ◽

Quark Mass ◽

Mass Difference ◽

Energy Scale ◽

Light Front ◽

Distribution Amplitude ◽

Chiral Quark Model ◽

Current Quark Mass ◽

Difference Formula ◽

Current Quark

We investigate the pseudoscalar (PS) meson ([Formula: see text] and [Formula: see text]) quasi-distribution amplitude (QDA), which is supposed to be an asymptotic analog to the meson distribution amplitude (DA) [Formula: see text] in the limit of the large longitudinal PS-meson momentum, i.e. [Formula: see text], in the non-perturbative (NP) region. For this purpose, we employ the nonlocal chiral-quark model (NLChQM) in the light-front (LF) formalism with a minimal Fock-state for the mesons [Formula: see text][Formula: see text][Formula: see text] at the low-energy scale parameter of the model [Formula: see text][Formula: see text][Formula: see text][Formula: see text]1 GeV. As a trial, we extract the transverse-momentum distribution amplitude (TMDA) from the light-front wave function (LFWF) within the model, and convert it to QDA with help of the virtuality-distribution amplitude (VDA). By doing that, we derive an analytical expression for the NP QDA with the current-quark mass correction up to [Formula: see text]. Numerically, we confirm that the obtained TMDA reproduces the experimental data for the photon-pion transition form factor [Formula: see text] at the low-[Formula: see text] qualitatively well. We also observe that the obtained QDA approaches to DA as [Formula: see text] increases, showing the symmetric and asymmetric curves with respect to [Formula: see text] for the pion and kaon, respectively, due to the current-quark mass difference [Formula: see text]. Assigning [Formula: see text], the moments [Formula: see text] are computed, using the pion and kaon QDAs, and there appear only a few percent deviations in the moments for [Formula: see text] in comparison to the values calculated directly from DAs. It turns out that the higher moments are more sensitive to the change of [Formula: see text], whereas the lower ones depend less on it.

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