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Constraints to the EOS of ultradense matter with model-independent astrophysical observations

G. Lavagetto·I. Bombaci·A. D'Ai'·I. Vidana·N. R. Robba
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Abstract

The recent discovery of burst oscillations at 1122 Hz in the x-ray transient XTE J1739-285, together with the measurement of the mass of the binary millisecond pulsar PSR J0751+1807 (2.1 +- 0.2 solar masses) can finally allow us to put strong, model-independent observational constraints to the equation of state of compact stars. We show that the measurement of the moment of inertia of PSR J0737+3039A, together with these constraints, could allow to discriminate further the details of the inner structure of neutron stars. Moreover, we show that if XTE J1739-285 is constituted of nucleonic matter, any equation of state allows only a narrow range of very high masses, and this could explain why up to now compact stars spinning faster than a millisecond have been so difficult to detect.

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G. Lavagetto, I. Bombaci, A. D'Ai', I. Vidana, N. R. Robba. 2006-12-03. Constraints to the EOS of ultradense matter with model-independent astrophysical observations. https://arxiv.org/abs/astro-ph/0612061

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