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تسجيل مستخدم جديدConstraints from the GW170817 merger event on the nuclear matter equation of state
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The detection of the GW170817 neutron star merger event has incited an intense research activity towards the understanding of the nuclear matter equation of state. In this paper we compare in particular the pressure-density relation obtained from heavy-ion collisions with the analysis of the NS merger event. Moreover, we present recent calculations of neutron stars moment of inertia and tidal deformability using various microscopic equations of state for nuclear and hybrid star configurations, and confirm several universal relations. We also discuss the recent constraints for the NS radii determined by GW170817, and find compatible radii between 12 and 13 kilometers, thus identifying the suitable equations of state.
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Constraints set on key parameters of the nuclear matter equation of state (EoS) by the values of the tidal deformability, inferred from GW170817, are examined by using a diverse set of relativistic and non-relativistic mean field models. These models
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We perform a systematic study of the dependence of the r-mode phenomenology in normal fluid pulsar neutron stars on the symmetry energy slope parameter $L$. An essential ingredient in this study is the bulk viscosity, which is evaluated consistently
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The recent direct detection of gravitational waves (GWs) from binary black hole mergers (2016, Phys. Rev. Lett. 116, no. 6, 061102; no. 24, 241103) opens up an entirely new non-electromagnetic window into the Universe making it possible to probe phys
ics that has been hidden or dark to electromagnetic observations. In addition to cataclysmic events involving black holes, GWs can be triggered by physical processes and systems involving neutron stars. Properties of neutron stars are largely determined by the equation of state (EOS) of neutron-rich matter, which is the major ingredient in calculating the stellar structure and properties of related phenomena, such as gravitational wave emission from elliptically deformed pulsars and neutron star binaries. Although the EOS of neutron-rich matter is still rather uncertain mainly due to the poorly known density dependence of nuclear symmetry energy at high densities, significant progress has been made recently in constraining the symmetry energy using data from terrestrial nuclear laboratories. These constraints could provide useful information on the limits of GWs expected from neutron stars. Here after briefly reviewing our previous work on constraining gravitational radiation from elliptically deformed pulsars with terrestrial nuclear laboratory data in light of the recent gravitational wave detection, we estimate the maximum gravitational wave strain amplitude, using an optimistic value for the breaking strain of the neutron star crust, for 15 pulsars at distances 0.16 kpc to 0.91 kpc from Earth, and find it to be in the range of $sim[0.2-31.1]times 10^{-24}$, depending on the details of the EOS used to compute the neutron star properties. Implications are discussed.
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