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Hybrid stars that masquerade as neutron stars

Mark Alford·Matt Braby·Mark Paris·Sanjay Reddy
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Abstract

We show that a hybrid (nuclear + quark matter) star can have a mass-radius relationship very similar to that predicted for a star made of purely nucleonic matter. We show this for a generic parameterization of the quark matter equation of state, and also for an MIT bag model, each including a phenomenological correction based on gluonic corrections to the equation of state. We obtain hybrid stars as heavy as 2 M_solar for reasonable values of the bag model parameters. For nuclear matter, we use the equation of state calculated by Akmal, Pandharipande, and Ravenhall using many-body techniques. Both mixed and homogeneous phases of nuclear and quark matter are considered.

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Mark Alford, Matt Braby, Mark Paris, Sanjay Reddy. 2005-04-25. Hybrid stars that masquerade as neutron stars. https://doi.org/10.1086/430902

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