Dense Nuclear Matter And Gravitational Waves From Binary Neutron Star Merger

Neutron star(NS)physics,as a cross-disciplinary area of astrophysics and nuclear physics,has been a focal point of research in physics.They are important sources of electromagnetic pulse signals and gravitational waves(GWs)signals.Research related to NS has been awarded several Nobel Prizes,highlighting the valuable research significance of NS.NS also provides a unique opportunity to study the microscopic composition and fundamental laws of matter in particle physics,particularly the strong interaction,which is one of the four fundamental interactions and has an unclear interaction mechanism in the non-perturbative region.The extreme conditions required for studying low-energy strong interactions cannot be created in the laboratory,but they exist in neutron stars.To address these issues,an effective field model for dense matter named the pseudoconformal model has been established,which considers the emergent symmetry that is hidden in the QCD matter-free vacuum and emerges in dense matter.This model incorporates the interaction between nucleons and π mesons into the basic framework of chiral effective field theory,introduces vector mesons ρ and ω by hiding local symmetry,and introduces the lightest scalar meson f0(500)with JPC=0++ as the dilaton particle a arisen from the spontaneous breaking of scale symmetry based on QCD trace anomaly and scale symmetry.Additionally,the topological model of nucleons predicts the existence of a topological phase changeover in the high-density region of strong interaction matter that differs from the low-density nuclear structure.By considering the topological changeover of such dense nuclear matter at high densities,the pseudo-conformal model can calculate the properties of dense nuclear matter,including the speed of sound which approaches the conformal limit at high densities.In this thesis,the pseudo-conformal model is used to calculate the properties of dense nuclear matter through the Vlow-k RG method,which verifies the consistency of its highdensity results with previously predicted results.Additionally,this thesis examines the possible vector manifestation of chiral symmetry in dense nuclear matter and its impact on nuclear matter and consequently neutron star properties.Furthermore,fully general-relativistic simulations of binary neutron star mergers are performed for nuclear matter equations of state with different topological transition points,and their observable effects in gravitational wave waveforms are predicted.Additionally,in this thesis,the impact of different order forms of the hadron-quark deconfinement phase transition on dense matter and neutron star properties is calculated,and numerical relativistic simulations of binary neutron star mergers with different forms of the deconfinement phase transition are designed to investigate possible observable evidences of deconfinement phase transition in gravitational waves.