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arXiv · hep-ph/9905356

Is SAX J1808.4-3658 a Strange Star ?

Abstract

One of the most important questions in the study of compact objects is the nature of pulsars, including whether they are composed of $β$-stable nuclear matter or strange quark matter. Observations of the newly discovered millisecond X-ray pulsar \sax with the Rossi X-Ray Timing Explorer place firm constraint on the radius of the compact star. Comparing the mass - radius relation of \sax with the theoretical mass - radius relation for neutron stars and for strange stars, we find that a strange star model is more consistent with SAX J1808.4-3658, and suggest that it is a likely strange star candidate.

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X. -D. Li, I. Bombaci, Mira Dey, Jishnu Dey, E. P. J. van den Heuvel. 1999-05-21. Is SAX J1808.4-3658 a Strange Star ?. https://doi.org/10.1103/physrevlett.83.3776

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