Pith. sign in

REVIEW 7 cited by

Impact of the PSR J0740+6620 radius constraint on the properties of high-density matter

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2106.05313 v3 pith:P5EKK2JQ submitted 2021-06-09 astro-ph.HE gr-qcnucl-th

classification astro-ph.HEgr-qcnucl-th
keywords neutrondensityj0740observationsstarbrancheossgravitational-wave
verification ladder T0 review T1 audit T2 compute T3 formal
0 comments
abstract

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 investigate this measurement's implications for the neutron star equation of state (EoS), employing a nonparametric EoS model based on Gaussian processes and combining information from other x-ray, radio and gravitational-wave observations of neutron stars. Our analysis mildly disfavors EoSs that support a disconnected hybrid star branch in the mass-radius relation, a proxy for strong phase transitions, with a Bayes factor of $6.9$. For such EoSs, the transition mass from the hadronic to the hybrid branch is constrained to lie outside ($1,2$) $M_{\odot}$. We also find that the conformal sound-speed bound is violated inside neutron star cores, which implies that the core matter is strongly interacting. The squared sound speed reaches a maximum of $0.75^{+0.25}_{-0.24}\, c^2$ at $3.60^{+2.25}_{-1.89}$ times nuclear saturation density at 90% credibility. Since all but the gravitational-wave observations prefer a relatively stiff EoS, PSR J0740+6620's central density is only $3.57^{+1.3}_{-1.3}$ times nuclear saturation, limiting the density range probed by observations of cold, nonrotating neutron stars in $\beta$-equilibrium.

Discussion (0). Continue with ORCID to comment.

Forward citations

Cited by 7 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. From Multimessenger Inference to Simulations: A Ranked Ensemble of Finite-Temperature Equations of State

    astro-ph.HE 2026-08 conditional novelty 7.0 of 10

    The paper constructs a 12-member ensemble of finite-temperature neutron star equations of state that spans the posterior from multimessenger and nuclear-physics constraints and releases simulation-ready tables.

  2. Quarkyonic Stars with Strangeness

    nucl-th 2026-07 conditional novelty 6.0 of 10

    A three-flavor quarkyonic model with octet baryons yields stiffer neutron-star EOS and raises maximum masses, potentially resolving the hyperon puzzle.

  3. Rotating Fermion-Boson Stars in $R$-squared Gravity

    gr-qc 2026-07 conditional novelty 6.0 of 10

    R-squared gravity enlarges the equilibrium domain of rotating fermion-boson stars and raises static and Keplerian maximum masses relative to GR while remaining compatible with current compact-object constraints.

  4. Reconstructing Critical Current Density in Josephson Junctions with Phase Non-linearity

    cond-mat.supr-con 2025-08 unverdicted novelty 5.0 of 10

    The standard Dynes-Fulton reconstruction of critical current density breaks down for junctions with nonlinear phase distributions, and the authors propose an iterative algorithm that incorporates prior knowledge to fix it.

  5. Properties of compact objects in quadratic non-metricity gravity

    gr-qc 2025-07 reject novelty 4.0 of 10

    Quadratic non-metricity gravity with a fitted coupling ξ can match PSR J0740+6620 while keeping the radial sound speed below c²/3, according to the paper's chosen metric ansatz.

  6. Toward a Unified Understanding of the Dense Matter Equation of State

    nucl-th 2025-11 conditional novelty 2.0 of 10

    A review of three Bayesian/computational frameworks for combining heavy-ion and astrophysical constraints on the dense-matter equation of state, plus a proposed unified integration workflow.

  7. Nuclear matter equation of state and astrophysics

    nucl-th 2026-07 conditional

    A review of multimessenger constraints on the neutron-star equation of state, arguing composition remains undetermined and advocating a multidimensional EoS framework and the author-affiliated MUSES software.

Pith tools