BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//CERN//INDICO//EN
BEGIN:VEVENT
SUMMARY:Hadronic and partonic composition of QCD matter across the crossov
 er
DTSTART;VALUE=DATE-TIME:20260922T132500Z
DTEND;VALUE=DATE-TIME:20260922T133000Z
DTSTAMP;VALUE=DATE-TIME:20260914T044407Z
UID:indico-contribution-528@indico.bitp.kiev.ua
DESCRIPTION:Speakers: Artemiy Lysenko (Bogolyubov Institute of Theoretical
  Physics)\nWe construct a simple equation of state of strongly interacting
  matter at zero chemical potentials that provides a unified description of
  lattice QCD thermodynamics in terms of hadronic and partonic degrees of f
 reedom. The hadronic phase is described by the quantum van der Waals hadro
 n resonance gas\, extended by excluded-volume repulsion between mesons\, w
 hile the quark-gluon plasma is modeled as an ideal gas of quarks and gluon
 s supplemented with a phenomenological interaction term proportional to $T
 ^3$. The two regimes are connected by a smooth crossover switching functio
 n. The three model parameters - the meson hard-core radius\, the strength 
 of the partonic interaction term\, and the switching temperature - are det
 ermined from a fit to lattice QCD results for the trace anomaly. The resul
 ting equation of state reproduces the lattice data on the pressure\, entro
 py density\, energy density\, and speed of sound in the temperature range 
 $T=100-500$ MeV. The fit yields a meson hard-core radius $r_M \\simeq 0.2$
  fm\, a partonic interaction scale $A \\simeq 600$ MeV\, and a switching t
 emperature $T_0 \\simeq 216$ MeV\, substantially exceeding both the pseudo
 critical temperature of the QCD chiral crossover and the chemical freeze-o
 ut temperature. This finding suggests that the transition from hadronic to
  partonic degrees of freedom is considerably more gradual than indicated b
 y the chiral pseudocritical temperature alone\, with hadronic states remai
 ning an important component of strongly interacting matter up to temperatu
 res of about $250$ MeV\, well above the QCD chiral crossover.\n\nhttps://i
 ndico.bitp.kiev.ua/event/18/contributions/528/
LOCATION:Bogolyubov Institute for Theoretical Physics Conference Hall
URL:https://indico.bitp.kiev.ua/event/18/contributions/528/
END:VEVENT
END:VCALENDAR