An updated mass-radius analysis of the 2017-2018 NICER data set of PSR J0030+0451
read the original abstract
In 2019 the NICER collaboration published the first mass and radius inferred for PSR J0030+0451, thanks to NICER observations, and consequent constraints on the equation of state characterising dense matter. Two independent analyses found a mass of $\sim 1.3-1.4\,\mathrm{M_\odot}$ and a radius of $\sim 13\,$km. They also both found that the hot spots were all located on the same hemisphere, opposite to the observer, and that at least one of them had a significantly elongated shape. Here we reanalyse, in greater detail, the same NICER data set, incorporating the effects of an updated NICER response matrix and using an upgraded analysis framework. We expand the adopted models and jointly analyse also XMM-Newton data, which enables us to better constrain the fraction of observed counts coming from PSR J0030+0451. Adopting the same models used in previous publications, we find consistent results, although with more stringent inference requirements. We also find a multi-modal structure in the posterior surface. This becomes crucial when XMM-Newton data is accounted for. Including the corresponding constraints disfavors the main solutions found previously, in favor of the new and more complex models. These have inferred masses and radii of $\sim [1.4 \mathrm{M_\odot}, 11.5$ km] and $\sim [1.7 \mathrm{M_\odot}, 14.5$ km], depending on the assumed model. They display configurations that do not require the two hot spots generating the observed X-rays to be on the same hemisphere, nor to show very elongated features, and point instead to the presence of temperature gradients and the need to account for them.
This paper has not been read by Pith yet.
Forward citations
Cited by 13 Pith papers
-
Causality alone bounds the maximum radius difference between different-mass neutron stars
Causality anchored to χEFT at low density implies the closed-form bound R(2.0 M_⊙) ≤ 1.16 R(1.4 M_⊙) − 1.1 km for neutron stars sharing one causal EoS, saturated by an analytic one-parameter family.
-
The Non-parametric Equation of State Realizes a Generalized Quark-Hadron Crossover
Non-parametric EOS construction from crust to pQCD forces a sound-speed peak and softening that realizes a generalized quark-hadron crossover in massive neutron stars.
-
Is the coexistence of strange quark stars and hadronic stars favored by astrophysical data? A Bayesian analysis
Bayesian analysis of astrophysical and laboratory data favors the two-families scenario of coexisting hadronic and strange quark stars over the one-family scenario.
-
The Non-parametric Equation of State Realizes a Generalized Quark-Hadron Crossover
Non-parametric EOS construction shows non-conformal behavior with evidence for soft quark matter and a hadron-quark phase transition in massive neutron star cores.
-
Hadronic lensing
Hadrons described by the nonlinear sigma model minimally coupled to Maxwell theory modify photon paths away from null geodesics, enabling analytic hadronic corrections to gravitational lensing deflection angles.
-
Hadronic lensing
Hadrons modeled by the nonlinear sigma model give photons a coordinate-dependent effective mass, yielding analytic expressions for the refractive index and a hadronic correction to the weak-field deflection angle arou...
-
Emulator-Assisted Nuclear DFT Inference and Its Consequences for the Structure of Neutron Stars
Emulator-assisted Bayesian inference of an extended Skyrme EDF, jointly constrained by nuclear observables, ab initio calculations, and NICER data, produces posteriors yielding consistent neutron star crust and core p...
-
Properties of the neutron star crust informed by nuclear structure data
Bayesian NS EoS study using full nuclear posterior distributions and consistent crust modeling finds increased surface thickness and crustal moment of inertia relative to prior work.
-
Hybrid Stars with Post-Merger Rotation Profiles
Differential rotation in hybrid stars with deconfinement phase transition allows quasi-toroidal configurations with quark matter rings and leads to degeneracies in rotational profiles at mass-radius curve intersections.
-
Bayesian analysis of density profile of light dark matter elucidating the properties of dark matter admixed neutron stars in the presence of hyperons
Bayesian analysis finds that the likely ranges of light dark-matter fermion mass and exponential density-profile parameter in hyperon-containing neutron stars are nearly independent of the hadronic model for symmetry-...
-
Neutron star with dark matter using vector portal
Vector portal fermionic dark matter admixed in neutron stars produces mediator-mass-dependent changes to the equation of state, yielding distinct mass-radius relations and tidal deformabilities that observations can u...
-
Sensitivity of the Neutron Star Equation of State Inferences to Mass and Radius Measurements
Theoretical inputs and the 2 solar mass lower limit dominate neutron star equation of state constraints across most densities, while radius data refines low densities and higher masses affect wider ranges.
-
Equation of State Extrapolation Systematics: Parametric vs. Nonparametric Inference of Neutron Star Structure
Nonparametric GP-based high-density extensions yield softer EOS posteriors with larger uncertainties than parametric PP extensions when jointly constrained by multi-messenger neutron star observations.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.