Publications (17)
Implicit correlations within phenomenological parametric models of the neutron star equation of state
Isaac Legred, Katerina Chatziioannou, Reed Essick +1
The rapid increase in the number and precision of astrophysical probes of neutron stars in recent years allows for the inference of their equation of state. Observations target dif…
Binary neutron star mergers using a discontinuous Galerkin-finite difference hybrid method
Nils Deppe, Francois Foucart, Marceline S. Bonilla +18
We present a discontinuous Galerkin-finite difference hybrid scheme that allows high-order shock capturing with the discontinuous Galerkin method for general relativistic magnetohy…
Studying the QCD Matter produced in Heavy-Ion Collisions using the MUSES Calculation Engine
Johannes Jahan, Kevin P. Pala, Yumu Yang +42
The equation of state of hot and dense matter is essential for describing heavy-ion collisions at all collision energies. Here, we explore the capabilities of the latest version of…
Neural-Accelerated Bayesian Calibration of Chiral Mean-Field Models to Nuclear Saturation and Vacuum Properties
Isaac Legred, Mateus Reinke Pelicer, Veronica Dexheimer +2
The paper presents a neural‑accelerated Bayesian framework that uses a surrogate neural network to efficiently calibrate chiral mean‑field nuclear interaction models against nuclea…
Simulating magnetized neutron stars with discontinuous Galerkin methods
Nils Deppe, François Hébert, Lawrence E. Kidder +33
Discontinuous Galerkin methods are popular because they can achieve high order where the solution is smooth, because they can capture shocks while needing only nearest-neighbor com…
Impact of the PSR J0740+6620 radius constraint on the properties of high-density matter
Isaac Legred, Katerina Chatziioannou, Reed Essick +2
X-ray pulse profile modeling of PSR J0740+6620, the most massive known pulsar, with data from the NICER and XMM-Newton observatories recently led to a measurement of its radius. We…
Unified nonparametric equation-of-state inference from the neutron-star crust to perturbative-QCD densities
Eliot Finch, Isaac Legred, Katerina Chatziioannou +3
Perturbative quantum chromodynamics (pQCD), while valid only at densities exceeding those found in the cores of neutron stars, could provide constraints on the dense-matter equatio…
Nonlinear Alfvén-wave Dynamics and Premerger Emission from Crustal Oscillations in Neutron Star Mergers
Elias R. Most, Yoonsoo Kim, Katerina Chatziioannou +1
Neutron stars have solid crusts threaded by strong magnetic fields. Perturbations in the crust can excite non-radial oscillations, which can in turn launch Alfven waves into the ma…
Inferring the neutron star equation of state with nuclear-physics informed semiparametric models
Sunny Ng, Isaac Legred, Lami Suleiman +3
Over the past decade, an abundance of information from neutron-star observations, nuclear experiments and theory has transformed our efforts to elucidate the properties of dense ma…
Simulating neutron stars with a flexible enthalpy-based equation of state parametrization in SpECTRE
Isaac Legred, Yoonsoo Kim, Nils Deppe +4
Numerical simulations of neutron star mergers represent an essential step toward interpreting the full complexity of multimessenger observations and constraining the properties of…
Using Equation of State Constraints to Classify Low-Mass Compact Binary Mergers
Jacob Golomb, Isaac Legred, Katerina Chatziioannou +2
Compact objects observed via gravitational waves are classified as black holes or neutron stars primarily based on their inferred mass with respect to stellar evolution expectation…
Nonparametric extensions of nuclear equations of state: probing the breakdown scale of relativistic mean-field theory
Isaac Legred, Liam Brodie, Alexander Haber +2
Phenomenological calculations of the properties of dense matter, such as relativistic mean-field theories, represent a pathway to predicting the microscopic and macroscopic propert…
Phase Transition Phenomenology with Nonparametric Representations of the Neutron Star Equation of State
Reed Essick, Isaac Legred, Katerina Chatziioannou +2
Astrophysical observations of neutron stars probe the structure of dense nuclear matter and have the potential to reveal phase transitions at high densities. Most recent analyses a…
Assessing equation of state-independent relations for neutron stars with nonparametric models
Isaac Legred, Bubakar O. Sy-Garcia, Katerina Chatziioannou +1
Relations between neutron star properties that do not depend on the nuclear equation of state offer insights on neutron star physics and have practical applications in data analysi…
The interplay of astrophysics and nuclear physics in determining the properties of neutron stars
Jacob Golomb, Isaac Legred, Katerina Chatziioannou +1
Neutron star properties depend on both nuclear physics and astrophysical processes, and thus observations of neutron stars offer constraints on both large-scale astrophysics and th…
Low-mass failed supernovae and the peak in the merging black hole mass distribution
Isaac Legred, Jacob Golomb, Katerina Chatziioannou
Gravitational-wave observations reveal that the rate of merging black holes drops by orders of magnitude from component masses to .…
Why Stellar Sequences Turn Over: Fixed Points, Instability, and Equation-of-State Universality
Isaac Legred, Nicolas Yunes
We reformulate the stellar structure equations in the language of dynamical systems and show that the maximum mass of stellar sequences arises from the existence of a fixed point i…