Restoring canonical partition functions from imaginary chemical potential
School of Biomedicine, Far Eastern Federal University, Sukhanova 8, 690950 Vladivostok, Russia
2 Institute for High Energy Physics NRC Kurchatov Institute, 142281 Protvino, Russia
3 School of Natural Sciences, Far Eastern Federal University, Sukhanova 8, 690950 Vladivostok, Russia
4 Institute of Theoretical and Experimental Physics NRC Kurchatov Institute, 117218 Moscow, Russia
5 Theoretical Research Division, Nishina Center, RIKEN, Wako 351-0198, Japan
6 Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki, Osaka, 567-0047, Japan
7 Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141700 Russia
* Speaker, e-mail: firstname.lastname@example.org
Published online: 26 March 2018
Using GPGPU techniques and multi-precision calculation we developed the code to study QCD phase transition line in the canonical approach. The canonical approach is a powerful tool to investigate sign problem in Lattice QCD. The central part of the canonical approach is the fugacity expansion of the grand canonical partition functions. Canonical partition functions Zn(T) are coefficients of this expansion. Using various methods we study properties of Zn(T). At the last step we perform cubic spline for temperature dependence of Zn(T) at fixed n and compute baryon number susceptibility χB/T2 as function of temperature. After that we compute numerically ∂χ/∂T and restore crossover line in QCD phase diagram. We use improved Wilson fermions and Iwasaki gauge action on the 163 × 4 lattice with mπ/mρ = 0.8 as a sandbox to check the canonical approach. In this framework we obtain coefficient in parametrization of crossover line Tc(µ2B) = Tc(C−ĸµ2B/T2c) with ĸ = −0.0453 ± 0.0099.
© The Authors, published by EDP Sciences, 2018
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