Curvature of the chiral phase transition line from the magnetic equation of state of (2+1)-flavor QCD

Abstract

We analyze the dependence of the chiral phase transition temperature on baryon number and strangeness chemical potentials by calculating the leading order curvature coefficients in the light and strange quark flavor basis as well as in the conserved charge ($B,S$) basis. Making use of scaling properties of the magnetic equation of state (MEoS) and including diagonal as well as off-diagonal contributions in the expansion of the energy-like scaling variable that enters the parametrization of the MEoS, allows to explore the variation of $T_c({\mu }_B,{\mu }_S)=T_c(1-({\kappa }_2^B{\hat{\mu }}_B^2+{\kappa }_2^S{\hat{\mu }}_S^2+2{\kappa }_{11}^{BS}{\hat{\mu }}_B{\hat{\mu }}_S))$ along different lines in the $({\mu }_B,{\mu }_S)$ plane. On lattices with fixed cut-off in units of temperature, $aT=1/8$, we find ${\kappa }_2^B=0.015(1)$, ${\kappa }_2^S=0.0124(5)$ and ${\kappa }_{11}^{BS}=-0.0050(7)$. We show that the chemical potential dependence along the line of vanishing strangeness chemical potential is about 10\% larger than along the strangeness neutral line. The latter differs only by about $3\%$ from the curvature on a line of vanishing strange quark chemical potential, ${\mu }_s=0$. We also show that close to the chiral limit the strange quark mass contributes like an energy-like variable in scaling relations for pseudo-critical temperatures. The chiral phase transition temperature decreases with decreasing strange quark mass, $T_c(m_s)=T_c(m_s^{\mathrm{phy}})(1-0.097(2)(m_s-m_s^{\mathrm{phys}})/m_s^{\mathrm{phy}}+\mathcal{O}((\Delta m_s{)}^2)$.

19 pages, 11 figures, updated to published version

References in corpus (9)

• The QCD Equation of State with almost Physical Quark Masses
• Highly Improved Staggered Quarks on the Lattice, with Applications to Charm Physics
• The QCD Equation of State to $\mathcal{O}({\mu }_B^6)$ from Lattice QCD
• The phase boundary for the chiral transition in (2+1)-flavor QCD at small values of the chemical potential
• QCD Critical Point and Complex Chemical Potential Singularities
• Second order cumulants of conserved charge fluctuations revisited I. Vanishing chemical potentials
• SIMULATeQCD: A simple multi-GPU lattice code for QCD calculations
• Scaling functions of the three-dimensional $Z(2)$, $O(2)$ and $O(4)$ models and their finite size dependence in an external field
• Microscopic Encoding of Macroscopic Universality: Scaling Properties of Dirac Eigenspectra near QCD Chiral Phase Transition

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• The QCD scalar susceptibility and thermal scalar resonances in chiral symmetry restoration
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• Towards a parameter-free analysis of the QCD chiral phase transition and its universal critical behavior