Physics of Particles and Nuclei

, Volume 46, Issue 5, pp 846–848 | Cite as

Mixed phase effects on high-mass twin stars

Article

Abstract

Recently it has been found that a certain class of hybrid star equations of state with a large latent heat (strong first order phase transition obtained by a Maxwell construction) between stiff hadronic and stiff quark matter phases allows for the appearance of a third family of compact stars (including “twins”) at high mass of ∼2 M We investigate how robust this high-mass twin phenomenon is against a smoothing of the transition which would occur, e.g., due to pasta structures in the mixed phase. To this end we propose a simple construction of a pasta-like equation of state with a parameter that quantifies the degree of smoothing of the transition and could eventually be related to the surface tension of the pasta structures. It is interesting to note that the range of energy densities for the transition as well as the pressure at the onset of the transition of this class of hybrid star matter at zero temperature corresponds well to values of the same quantities found in finite temperature lattice QCD simulations for the 1 σ region at the pseudocritical temperature Tc = 154 ± 9 MeV. The pattern of the speed of sound as a function of energy density is very different.

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References

  1. 1.
    M. Alford, D. Blaschke, A. Drago, et al., “Quark matter in compact stars?,” Nature 445, E7 (2007). astro-ph/0606524.CrossRefADSGoogle Scholar
  2. 2.
    N. K. Glendenning, Compact Stars: Nuclear Physics, Particle Physics, and General Relativity (Springer, New York, 2000).CrossRefGoogle Scholar
  3. 3.
    M. G. Alford, S. Han, and M. Prakash, “Generic conditions for stable hybrid stars,” Phys. Rev., D 88 (8), 083013 (2013).CrossRefADSGoogle Scholar
  4. 4.
    D. Blaschke, D. E. Alvarez Castillo, S. Benic, et al., Nonlocal PNJL Models and Heavy Hybrid Stars, PoS (Confinement X), 2012, p. 249; arXiv:1302.6275 [hep-ph].Google Scholar
  5. 5.
    D. Blaschke, D. E. Alvarez-Castillo, and S. Benic, Mass-Radius Constraints for Compact Stars and a Critical Endpoint," PoS (CPOD 2013), 063. 2013; arXiv:1310.3803 [nucl-th].Google Scholar
  6. 6.
    D. E. Alvarez-Castillo, S. Beni, D. Blaschke, and R. Lastowiecki, “Crossover transition to quark matter in heavy hybrid stars,” Acta Phys. Polon. Supp. 7 (1), 203 (2014).CrossRefGoogle Scholar
  7. 7.
    T. Kojo, P. D. Powell, Y. Song, and G. Baym, Phenomenological QCD Equation of State for Massive Neutron Stars, Phys. Rev. D 91, 045003 (2015).CrossRefADSGoogle Scholar
  8. 8.
    S. Benic, D. Blaschke, D. E. Alvarez-Castillo, et al., “A new quark-hadron hybrid equation of state for astrophysics, I. High-mass twin compact stars,” Astron. Astrophys. 577, A40 (2015).CrossRefADSGoogle Scholar
  9. 9.
    S. Benic, “Heavy hybrid stars from multi-quark interactions,” Eur. Phys. J., A 50, 111 (2014).CrossRefADSGoogle Scholar
  10. 10.
    D. Alvarez-Castillo, A. Ayriyan, D. Blaschke, and H. Grigorian, Bayesian Analysis of Hybrid EoS based on Astrophysical Observational Data, LIT Scientific Report 2011–2013, 2014, pp. 123–126; arXiv:1408.4449 [astro-ph.HE].Google Scholar
  11. 11.
    D. B. Blaschke, H. A. Grigorian, D. E. AlvarezCastillo, and A. S. Ayriyan, “Mass and radius constraints for compact stars and the QCD phase diagram,” J. Phys. Conf. Ser. 496, 012002 (2014).CrossRefADSGoogle Scholar
  12. 12.
    N. Yasutake, R. Lastowiecki, S. Benic, et al., “Finitesize effects at the hadron-quark transition and heavy hybrid stars,” Phys. Rev., C 89, 065803 (2014).CrossRefADSGoogle Scholar
  13. 13.
    A. Bazavov et al. (HotQCD Collab.), “The equation of state in (2+1)-flavor QCD,” Phys. Rev., D 90 (9), 094503 (2014).CrossRefADSGoogle Scholar
  14. 14.
    R. C. Tolman, “Static solutions of Einstein’s field equations for spheres of fluid,” Phys. Rev. 55, 364 (1939).CrossRefADSGoogle Scholar
  15. 15.
    J. R. Oppenheimer and G. M. Volkoff, “On massive neutron cores,” Phys. Rev. 55, 374 (1939).MATHCrossRefADSGoogle Scholar
  16. 16.
    S. Shapiro and S. Teukolsky, Black Holes, White Dwarfs, and Neutron Stars (Wiley and Sons, New York, 1983).CrossRefGoogle Scholar
  17. 17.
    J. Antoniadis, P. C. C. Freire, N. Wex, et al., “A massive pulsar in a compact relativistic Binary,” Science 340, 6131 (2013).CrossRefADSGoogle Scholar
  18. 18.
    P. Demorest, T. Pennucci, S. Ransom, et al., “Shapiro delay measurement of a two solar mass neutron star,” Nature 467, 1081–1083 (2010).CrossRefADSGoogle Scholar
  19. 19.
    Slavko Bogdanov, “The nearest millisecond pulsar revisited with XMM-newton: improved mass-radius constraints for PSR J0437-4715,” Astrophys. J. 762 (2), 96 (2013).CrossRefADSGoogle Scholar
  20. 20.
    H. Hambaryan, R. Neuhäuser, V. Suleimanov, and K. Werner, “Observational constraints of the compactness of isolated neutron stars,” J. Phys., Conference Ser. 496, 012015 (2014).CrossRefADSGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2015

Authors and Affiliations

  1. 1.Bogoliubov Laboratory of Theoretical PhysicsJINRDubnaRussia
  2. 2.Institute of Theoretical PhysicsUniversity of WrocławWrocławPoland

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