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Upper limit on the mass of RX J1856.5--3754 as a possible quark star

Kazunori Kohri·Kei Iida·Katsuhiko Sato
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Abstract

Recent deep Chandra LETG+HRC-S observations suggest the possibility that RX J1856.5--3754 is a compact star whose radiation radius is 3.8--8.2 km. In this paper, we systematically calculate the mass-radius relations of quark stars within the bag model. Assuming that RX J1856.5--3754 is a pure quark star, we derive an upper limit on its mass for various sets of the bag-model parameters.

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Kazunori Kohri, Kei Iida, Katsuhiko Sato. 2003-04-19. Upper limit on the mass of RX J1856.5--3754 as a possible quark star. https://doi.org/10.1143/ptp.109.765

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