Soft equations of state for neutron-star matter ruled out by EXO 0748-676

The interiors of neutron stars contain matter at very high densities, in a state that differs greatly from those found in the early universe or achieved at terrestrial experiments. Matter in these conditions can only be probed through astrophysical observations that measure the mass and radius of neutron stars with sufficient precision. Here I report for the first time a unique determination of the mass and radius of the neutron star EXO 0748-676, which appears to rule out all the soft equations of state of neutron star matter. If this object is typical, then condensates and unconfined quarks do not exist in the centers of neutron stars.

neutron star: mass
neutron star: size
equation of state
binary
burst: oscillation
numerical calculations: interpretation of experiments

References(20)

Figures(0)

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