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Possible evidence of quark matter in neutron star X-ray binaries

Norman K. Glendenning·F. Weber
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Abstract

We study the spin evolution of X-ray neutron stars in binary systems, which are being spun up by mass transfer from accretion disks. Our investigation reveals that a quark phase transition resulting from the changing central density induced by the changing spin, can lead to a pronounced peak in the frequency distribution of X-ray neutron stars. This finding provides one of several possible explanations available in the literature, or at least a contributor to part of the observed anomalous frequency distribution of neutron stars in low-mass X-ray binaries (LMXBs), which lie in a narrow band centered at about 300 Hz, as found by the Rossi Explorer (RXTE).

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Norman K. Glendenning, F. Weber. 2000-09-05. Possible evidence of quark matter in neutron star X-ray binaries. https://doi.org/10.1086/323972

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