Exploring Quark Matter under Extreme Scenarios of Temperature and Density

Dear Colleagues,

RHIC and LHC programs aim to explore and potentially discover a critical point or a first-order phase transition in the quantum chromodynamics (QCD) phase diagram. The significance of such a discovery lies in its implications for our understanding of QCD as it would signify a clear distinction between quark–gluon plasma (QGP) and hadronic matter. Collisions at very high energies explore a regime akin to that of the early universe, i.e., characterized by high temperature and low baryon chemical potential. On the other hand, collisions at low energies create systems that closely resemble those found in neutron star mergers, featuring low temperature and high baryon chemical potential. Numerous intriguing questions arise from these collision regimes. Addressing these questions through dedicated studies will foster fruitful work in the fluid dynamics and transport theories of both heavy-ion physics and neutron stars.

The objective of this Special Issue is to compile a comprehensive assortment of both comprehensive reviews and novel research articles that describe nuclear theory and experiments in the context of heavy-ion collisions and mergers of two or more neutron stars. The topics in heavy-ion collisions encompass many-body theory and chiral effective field theory, perturbative QCD, transport coefficients, relativistic viscous fluid dynamics, jets, electromagnetic probes, collective dynamics, early time electromagnetic fields, baryon stopping and dynamics of conserved charges, polarization, and spin alignment. Additionally, from the realm of neutron star mergers, the addressed subjects include the examination of phase transition signatures, chemical equilibration and the role of magnetic fields. We cordially invite contributions from both the theoretical and experimental domains.

Points: jets; collective dynamics; electromagnetic probes; equation of state; transport coefficients in merger; phase transition; magnetic evolution; electromagnetic fields in heavy ion collisions and neutron star mergers; polarisation and spin alignment; conserved charge dynamics

Dr. Souvik Priyam Adhya
Dr. Sandeep Chatterjee
Dr. Sreemoyee Sarkar
Guest Editors

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• heavy ion collisions
• quark–gluon plasma
• hard probes
• collective dynamics
• saturation
• neutron star mergers
• equation of state
• transport coefficients
• electromagnetic probes
• chirality
• small systems