trailSome compact star observations are difficult to explain with conventional neutron star models
Some observed compact stars may be strange quark stars
Anomalously light and compact objects· for
The compact object in HESS J1731-347 has a mass near 0.77 solar masses and a radius near 10.4 km
The X-ray spectrum of the compact object in HESS J1731-347 is well described by a uniform-temperature carbon atmosphere model
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Hydrogen-atmosphere hot-spot models fit the X-ray spectrum of HESS J1731-347 as well as carbon-atmosphere models
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Conventional supernova mechanisms cannot readily produce neutron stars with masses well below one solar mass
atomic
The pulsar XTE J1814-338 has an inferred radius of about 7 km, smaller than neutron star models predict
Pulse profile modeling of XTE J1814-338's thermonuclear burst oscillations yields a radius near 7 km and a mass near 1.2 solar masses
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Standard nuclear-matter equations of state predict radii of about 11 to 13 km for neutron stars near 1.2 solar masses
Earlier pulse-shape modeling of XTE J1814-338's accretion-powered pulsations indicated a radius of roughly 12 to 22 km
Systematic uncertainties in the inferences· against
Inferred masses and radii of compact stars depend strongly on assumed distance and atmosphere composition
atomic
claim · empirical · derivedA factual claim that rests on inference from other evidence rather than direct observation.constitution →claim page ↗︎
Some compact star observations are difficult to explain with conventional neutron star models
↑SupportedThe evidence favors the claim, but the examination is incomplete or the evidence is indirect.constitution →credence 0.75Credence, from 0 to 1: the Steward's probability that the claim, as stated, is true. Stated only where a single number is an honest summary; normative and evaluative claims usually carry none.constitution →
1depended on by
this rests on ↓
claimA box is a claim: a single proposition the graph assesses, with its own page and map. Click any claim to centre the map on it.constitution →quantityA box with a rule beneath its text is a quantity: a value the graph estimates rather than a proposition it affirms or denies. Its estimate stands where a claim's status would.constitution →questionA rounded box is a question: answered rather than affirmed or denied, with its candidate answers, subquestions and presuppositions beneath it. Its mark says how well answered it is.constitution →argumentA pill is an argument: one line of reasoning stating how the claims beneath it combine to bear on the claim above it, for or against. Click one to see its reasoning and open its page.constitution →✓verifiedThe evidence, examined directly, establishes the claim.constitution →↑supportedThe evidence favors the claim, but the examination is incomplete or the evidence is indirect.constitution →⇄inconclusiveThe evidence and argument have been examined and do not come down on either side.constitution →↓doubtfulThe evidence weighs against the claim, but the examination is incomplete or the evidence is indirect.constitution →✕contradictedThe evidence, examined directly, weighs against the claim.constitution →?unknownInsufficient information to assess.constitution →◌unassessedNo current assessment. Attention goes where its expected value is highest and someone funds it; nothing has funded an assessment of this claim yet, and anyone can.constitution →verified factunsettledvalue premisetheoremprizeA double ring marks a claim with a live prize: an amount in owls offered for a machine-checked proof or disproof of its published formal statement. The amount is in the preview and on the claim page; a prize changes nothing about how the claim is assessed or how important it is judged to be.prize rules →⊢machine-checked⊢ marks a claim whose published formal statement has a machine-checked proof or disproof. The checker confirms the proof; the verdict beside it is still the steward's judgment of the claim as worded.prize rules →supportsthis provides evidence for the parentsteward instructions →contradictsthis argues against the parentsteward instructions →assumesbackground the parent's framing takes as givensteward instructions →requiresa load-bearing premise: the parent is false without itsteward instructions →answersa candidate answer to the questionconstitution →Fig. Detail falls off with distance; every claim is an address.