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DOE OSTI · 2575586

Kilonova Emissions from Neutron Star Merger Remnants: Implications for the Nuclear Equation of State

Lund, Kelsey Alexandra [North Carolina State University, Raleigh, NC (United States); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000300311397)·Somasundaram, Rahul [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Syracuse Univ., NY (United States)] (ORCID:0000000304273893)·McLaughlin, Gail C. [North Carolina State University, Raleigh, NC (United States)] (ORCID:0000000168116657)·Miller, Jonah Maxwell [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000164327860)·Mumpower, Matthew Ryan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000299509688)·Tews, Ingo [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000326566355)
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Abstract

Multimessenger observations of binary neutron star mergers can provide valuable information on the nuclear equation of state (EOS). Here, we investigate the extent to which electromagnetic observations of the associated kilonovae allow us to place constraints on the EOS. For this, we use state-of-the-art three-dimensional general-relativistic magnetohydrodynamics simulations and detailed nucleosynthesis modeling to connect properties of observed light curves to properties of the accretion disk, and hence, the EOS. Using our general approach, we use multimessenger observations of GW170817/AT2017gfo to study the impact of various sources of uncertainty on inferences of the EOS. We constrain the radius of a 1.4M ⊙ neutron star to lie within 10.30 ≤ R 1.4 ≤ 13.0 km and the maximum mass to be M TOV ≤ 3.06M ⊙ .

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS79 ASTRONOMY AND ASTROPHYSICSCompact objectsExplosive nucleosynthesisNeutron starsNuclear astrophysicsNucleosynthesisR-process

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Lund, Kelsey Alexandra [North Carolina State University, Raleigh, NC (United States); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000300311397), Somasundaram, Rahul [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Syracuse Univ., NY (United States)] (ORCID:0000000304273893), McLaughlin, Gail C. [North Carolina State University, Raleigh, NC (United States)] (ORCID:0000000168116657), Miller, Jonah Maxwell [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000164327860), Mumpower, Matthew Ryan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000299509688), Tews, Ingo [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000326566355). 2025-06-26. Kilonova Emissions from Neutron Star Merger Remnants: Implications for the Nuclear Equation of State. https://doi.org/10.3847/1538-4357%2Fadd148

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