Relations between neutron-star parameters in the Hartle-Thorne approximation

Michi Bauböck, Emanuele Berti, Dimitrios Psaltis, Feryal Ozel

Research output: Contribution to journalArticle

52 Citations (Scopus)

Abstract

Using stellar structure calculations in the Hartle-Thorne approximation, we derive analytic expressions connecting the ellipticity of the stellar surface to the compactness, the spin angular momentum, and the quadrupole moment of the spacetime. We also obtain empirical relations between the compactness, the spin angular momentum, and the spacetime quadrupole. Our formulae reproduce the results of numerical calculations to within a few percent and help reduce the number of parameters necessary to model the observational appearance of moderately spinning neutron stars. This is sufficient for comparing theoretical spectroscopic and timing models to observations that aim to measure the masses and radii of neutron stars and to determine the equation of state prevailing in their interiors.

Original languageEnglish (US)
Article number68
JournalAstrophysical Journal
Volume777
Issue number1
DOIs
StatePublished - Nov 1 2013

Fingerprint

void ratio
angular momentum
neutron stars
quadrupoles
stellar structure
ellipticity
approximation
equation of state
metal spinning
equations of state
time measurement
moments
radii
parameter
calculation

Keywords

  • gravitation
  • relativistic processes
  • stars: neutron

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Relations between neutron-star parameters in the Hartle-Thorne approximation. / Bauböck, Michi; Berti, Emanuele; Psaltis, Dimitrios; Ozel, Feryal.

In: Astrophysical Journal, Vol. 777, No. 1, 68, 01.11.2013.

Research output: Contribution to journalArticle

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