Large and massive neutron stars: Implications for the sound speed within QCD of dense matter

  title={Large and massive neutron stars: Implications for the sound speed within QCD of dense matter},
  author={C. Drischler and Sophia Han and Sanjay Reddy},
  journal={Physical Review C},
The NASA telescope NICER has recently measured x-ray emissions from the heaviest of the precisely known two-solar mass neutron stars, PSR J0740+6620. Analysis of the data [Miller et al., Astrophys. J. Lett. 918, L28 (2021); Riley et al., Astrophys. J. Lett. 918, L27 (2021)] suggests that PSR J0740+6620 has a radius in the range of R2.0 ≈ (11.4− 16.1) km at the 68% credibility level. In this article, we study the implications of this analysis for the sound speed in the high-density inner cores… 

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