Simulating Binary Neutron Stars with Hybrid Equation of States: Gravitational Waves, Electromagnetic Signatures and Challenges for Numerical Relativity

Gieg, Henrique; Dietrich, Tim; Ujevic, Maximiliano

doi:10.3390/particles2030023

Cited by 21 publications

(14 citation statements)

References 99 publications

(171 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The peak frequency for all signals is f peak ≈ 2 kHz, which falls within a low-sensitivity band for these detectors. We note that the short lived hybrid star remnant observed in [79] underwent oscillations which produced GWs with a peak frequency of approximately 3 kHz, which is comparable to our findings. For the distance considered, the GWs for the rotating cases in our study would be detectable by Advanced Ligo (aLIGO) [151], Einstein Telescope (ET) [152] and Cosmic Explorer (CE) [153].…”

Section: B Gravitational Wavessupporting

confidence: 90%

See 1 more Smart Citation

The fate of twin stars on the unstable branch: implications for the formation of twin stars

Espino,

Paschalidis

2021

Preprint

View full text Add to dashboard Cite

Hybrid hadron-quark equations of state that give rise a third family of stable compact stars have been shown to be compatible with the LIGO-Virgo event GW170817. Stable configurations in the third family are called hybrid hadron-quark stars. The equilibrium stable hybrid hadron-quark star branch is separated by the stable neutron star branch with a branch of unstable hybrid hadronquark stars. The end-state of these unstable configurations has not been studied, yet, and it could have implications for the formation and existence of twin stars -hybrid stars with the same mass as neutron stars but different radii. We modify existing hybrid hadron-quark equations of state with a first-order phase transition in order to guarantee a well-posed initial value problem of the equations of general relativistic hydrodynamics, and study the dynamics of non-rotating or rotating unstable twin stars via 3-dimensional simulations in full general relativity. We find that unstable twin stars naturally migrate toward the hadronic branch. Before settling into the hadronic regime, these stars undergo (quasi)radial oscillations on a dynamical timescale while the core bounces between the two phases. Our study suggests that it may be difficult to form stable twin stars if the phase transition is sustained over a large jump in energy density, and hence it may be more likely that astrophysical hybrid hadron-quark stars have masses above the twin star regime. We also study the minimum-mass instability for hybrid stars, and find that these configurations do not explode, unlike the minimummass instability for neutron stars. Additionally, our results suggest that oscillations between the two Quantum Chromodynamic phases could provide gravitational wave signals associated with such phase transitions in core-collapse supernovae and white dwarf-neutron star mergers.1 Henceforth we refer to EOSs which include both hadron and quark degrees of freedom as "hybrid EOSs", and stars that contain both hadronic and quark phases as "hybrid stars". Hybrid stars with the same mass as neutron stars are referred to as "twin stars."

show abstract

Section: B Gravitational Wavessupporting

confidence: 90%

“…to a third family of compact objects (as has also been suggested in [74,79], for example, following the merger of heavy neutron stars that form a remnant whose density is above the threshold for the quark deconfinement phase transition).…”

Section: Pressure Depletionmentioning

confidence: 74%

The fate of twin stars on the unstable branch: implications for the formation of twin stars

Espino,

Paschalidis

2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Snapshots of the configuration of the merger at various times in its evolution, obtained from numerical simulations, can be found in [186][187][188][189][190][191][192]. A few orbits after the stars begin to tidally deform, they collide with a relatively large impact parameter, which generates a shear interface that may lead to a Kelvin-Helmholtz instability [184,193].…”

Section: A Dynamics Of a Neutron Star Mergermentioning

confidence: 99%

Axions: From Magnetars and Neutron Star Mergers to Beam Dumps and BECs

Fortin,

Guo,

Harris

et al. 2021

Preprint

View full text Add to dashboard Cite

We review topics in searches for axion-like-particles (ALPs), covering material that is complementary to other recent reviews. The first half of our review covers ALPs in the extreme environments of neutron star cores, the magnetospheres of highly magnetized neutron stars (magnetars), and in neutron star mergers. The focus is on possible signals of ALPs in the photon spectrum of neutron stars and gravitational wave/electromagnetic signals from neutron star mergers. We then review recent developments in laboratory-produced ALP searches, focusing mainly on accelerator-based facilities including beam-dump type experiments and collider experiments. We provide a general-purpose discussion of the ALP search pipeline from production to detection, in steps, and our discussion is straightforwardly applicable to most beam-dump type and reactor experiments. We end with a selective look at the rapidly developing field of ultralight dark matter, specifically the formation of Bose-Einstein Condensates (BECs). We review the properties of BECs of ultralight dark matter and bridge these properties with developments in numerical simulations, and ultimately with their impact on experimental searches.

show abstract

“…The equations of state used in simulations are either piecewise polytropes [161] (often with the addition of a thermal part) or tabulated from nuclear-physics studies. The first general-relativistic simulations of merging neutron stars including quarks at finite temperatures have been performed recently [22,[24][25][26]35,90,139,140,199]. Some robust results have been obtained also in computations of ejecta from BNS mergers (especially for estimates of heavy-element production and kilonovae light curves) [176] and in the general-relativistic treatment of physical viscosity for BNSs [8,86,87,109,154,177,209].…”

Section: Introductionmentioning

confidence: 99%