A new approach is presented to explore the singularity structure of lattice QCD in the complex chemical potential plane. Our method can be seen as a combination of the Taylor expansion and analytic continuation approaches. Its novelty lies in using rational (Padé) approximants for studying Lee-Yang edge singularities. We present a calculation of the cumulants of the net-baryon number as a function of a purely imaginary baryon number chemical potential, obtained with highly improved staggered quarks at temporal lattice extent of N_tau=4,6. We construct various rational function approximations of the lattice data and determine their poles (and roots) in the complex plane. We compare the position of the closest pole to the theoretically expected position of the Lee-Yang edge singularity. At high temperature, we find scaling that is in accordance with the expected power law behavior of the Roberge-Weiss transition while a different behavior is found for T≲170 MeV.
Detecting Critical Points from the Lee-Yang Edge Singularities in Lattice QCD / Schmidt, C.; Clarke, D. A.; Nicotra, G.; Di Renzo, F.; Dimopoulos, P.; Singh, S.; Goswami, J.; Zambello, K.. - In: ACTA PHYSICA POLONICA B. - ISSN 0587-4254. - 16(1):(2023), pp. 1-A52.1-A52.1-1-A52.1-A52.6. (Intervento presentato al convegno 29th international conference on ultrarelativistic nucleus-nucleus collisions, Quark Matter 2022 tenutosi a Kraców (Poland) nel April 4-10, 2022) [10.5506/aphyspolbsupp.16.1-a52].
Detecting Critical Points from the Lee-Yang Edge Singularities in Lattice QCD
F. Di Renzo;P. Dimopoulos;S. Singh;K. Zambello
2023-01-01
Abstract
A new approach is presented to explore the singularity structure of lattice QCD in the complex chemical potential plane. Our method can be seen as a combination of the Taylor expansion and analytic continuation approaches. Its novelty lies in using rational (Padé) approximants for studying Lee-Yang edge singularities. We present a calculation of the cumulants of the net-baryon number as a function of a purely imaginary baryon number chemical potential, obtained with highly improved staggered quarks at temporal lattice extent of N_tau=4,6. We construct various rational function approximations of the lattice data and determine their poles (and roots) in the complex plane. We compare the position of the closest pole to the theoretically expected position of the Lee-Yang edge singularity. At high temperature, we find scaling that is in accordance with the expected power law behavior of the Roberge-Weiss transition while a different behavior is found for T≲170 MeV.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
