QCS2026

Overview

We are pleased to announce that international workshop (QCS 2026) will take place at Tokai, Ibaraki, Japan from 29 Apr to 2 May 2026.This workshop is one of the series of workshops among China, Japan, and Korea, to promote international cooperation and exchanges of scientific achievements and perspective in the field of high-density matter and compact stars.

Novel hadronic and/or quark phases are expected to be realized in high-density hadronic matter. Mechanisms of phase transitions and phase equilibrium between these phases should be clarified to obtain the QCD phase diagram. Toward understanding high-density matter in neutron stars (NSs) and formation processes of black holes (BHs) etc., the equation of state (EOS), describing the pressure-density relation, has a key role. In another aspect, dynamical properties of proto-neutron stars are described by the use of hot and dense supernova matter EOS with trapped neutrinos together with transport equations. These issues should be explored based on realistic interaction models that describe the hadron interactions including baryon-baryon and meson-baryon interactions for hadronic phases and quark-hadron and quark-quark interactions for hadron-quark transitions and quark phases. In addition, strangeness degrees of freedom such as hyperons, kaons, and strange quarks may have important effects on the phase structure of high-density matter. Furthermore, these model predictions should be confronted with information from not only lattice QCD results but also heavy-ion experiments and astrophysical observations. High-density matter that may be produced during heavy-ion collisions is one of emphasized topics of the workshop. In fact, heavy-ion experiment, at bombarding energies lower than the existing experiments, is discussed as one of the future projects of J-PARC facility.

Both young and senior researchers from nuclear and hadron physics, particle physics, astrophysics, condensed matter physics, and from these interdisciplinary fields are welcome to join us.

Topics

• Equation of state for compact stars, supernovae, and black hole formation

stiffening high-density EOS by three-baryon repulsions, effects of partial chiral symmetry restoration, reaction rates, etc.

• Various phases in hadronic matter and quark matter

baryon superfluidity, hyperon-mixed matter, meson condensation, inhomogeneous chiral density waves, quarkyonic matter, color superconductivity, etc.

• QCD phase diagram

hadron-quark phase transition, hadron-quark crossover, chiral phase transition, etc.

• Theoretical approaches for high-density matter

relativistic mean-field models, chiral perturbation theory, chiral effective models for hadrons, chiral quark models, lattice QCD, etc.

• Heavy-ion collision experiments and high-density matter

hyperon(Y)-nucleon (N), YY interactions, density-dependence of symmetry energy and slope, hadron correlations by femtoscopy, etc.

• Observations and properties of compact stars

NS mass and radius by NICER observations, gravitational waves and multi-messenger observations, neutrinos from supernovae, glitches, etc.

• High-energy astrophysics

NS-NS mergers, supernovae, cooling history and heating of compact stars, low-mass X-ray bursts, etc.

• Other related topics

Registration and Registration Fee

Registration is now open, and the deadline is 15 Apr. 2026. 

Registration fee (includes Banquet and 4 Lunchboxes): We accept credit cards (MasterCard, Visa, Diners, Amex, and JCB)

* About Cancellation: Since April 16 JST 24:00, 10,000 JPY is required to be paid for registrars who cancel.

Previous QCS conference info.

* This workshop is supported by

• Advanced Science Research Center, JAEA
• KMI for the Origin of Particles and the Universe
• RCNP, Osaka University
• RIKEN iTHEMS Working Group GWX-EOS