Spectral lines from rotating neutron stars

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

The line profiles from rotating neutron stars are affected by a number of relativistic processes such as Doppler boosts, strong self-lensing, frame dragging, and the differential gravitational redshift arising from the stellar oblateness. In this Letter, we calculate line profiles, taking into account the first two effects; this approach is accurate for rotation rates less than the breakup frequency. We show that the line profiles are not only broadened and weakened but are also significantly asymmetric, and allow for an independent measurement of both the mass and the radius of the neutron star. Furthermore, we investigate the case when a fraction of the neutron star surface contributes to the emission and find that the line profiles are typically doubly peaked. We discuss the implications of our results for searches for line features in the spectra of isolated neutron stars and X-ray bursters. We finally assess the systematic uncertainties introduced by the line asymmetry in inferring the compactness of neutron stars from the detection of redshifted lines.

Original languageEnglish (US)
JournalAstrophysical Journal
Volume582
Issue number1 II
DOIs
StatePublished - Jan 1 2003
Externally publishedYes

Fingerprint

neutron stars
line spectra
asymmetry
profiles
void ratio
acceleration (physics)
detection
rate
effect
radii
x rays

Keywords

  • Relativity
  • Stars: neutron
  • X-rays: stars

ASJC Scopus subject areas

  • Space and Planetary Science

Cite this

Spectral lines from rotating neutron stars. / Ozel, Feryal; Psaltis, Dimitrios.

In: Astrophysical Journal, Vol. 582, No. 1 II, 01.01.2003.

Research output: Contribution to journalArticle

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