Publications by authors named "Ingo Tews"
Article Synopsis
- The detection of gravitational-wave signal GW170817 and its associated phenomena (kilonova and gamma-ray burst) marked a significant advance in astrophysics, indicating the need for strong theoretical models to interpret these diverse signals.
- The NMMA framework was developed to integrate nuclear-physics data and observational evidence, helping to analyze the behaviors of dense matter in neutron stars.
- This paper presents an extension of the NMMA code to simultaneously analyze the signals from GW170817, the kilonova, and the gamma-ray burst, allowing for the estimation of a neutron star's radius.
Interpreting high-energy, astrophysical phenomena, such as supernova explosions or neutron-star collisions, requires a robust understanding of matter at supranuclear densities. However, our knowledge about dense matter explored in the cores of neutron stars remains limited. Fortunately, dense matter is not probed only in astrophysical observations, but also in terrestrial heavy-ion collision experiments.
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- The symmetry energy and its density dependence are essential for understanding nuclear structure and astrophysical phenomena, affecting characteristics like neutron-skin thickness and neutron star properties.
- Recent measurements from PREX-II suggested a neutron-skin thickness for ^{208}Pb that indicates a higher slope parameter (L) than previously reported, raising questions about existing theoretical models.
- Utilizing data from neutron stars and combining it with PREX-II and other constraints, researchers derived new values for key parameters, concluding a smaller neutron skin thickness and a reduced slope parameter (L), with specific numerical ranges provided for symmetry energy and thickness.
We perform a joint Bayesian inference of neutron-star mass and radius constraints based on GW170817, observations of quiescent low-mass x-ray binaries (QLMXBs), photospheric radius expansion x-ray bursting sources, and x-ray timing observations of J0030+0451. With this dataset, the form of the prior distribution still has an impact on the posterior mass-radius curves and equation of state (EOS), but this impact is smaller than recently obtained when considering QLMXBs alone. We analyze the consistency of the electromagnetic data by including an "intrinsic scattering" contribution to the uncertainties, and find only a slight broadening of the posteriors.
View Article and Find Full Text PDFObservations of neutron-star mergers with distinct messengers, including gravitational waves and electromagnetic signals, can be used to study the behavior of matter denser than an atomic nucleus and to measure the expansion rate of the Universe as quantified by the Hubble constant. We performed a joint analysis of the gravitational-wave event GW170817 with its electromagnetic counterparts AT2017gfo and GRB170817A, and the gravitational-wave event GW190425, both originating from neutron-star mergers. We combined these with previous measurements of pulsars using x-ray and radio observations, and nuclear-theory computations using chiral effective field theory, to constrain the neutron-star equation of state.
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