Strange S tar or Neutron S tar EoS & Current Observation

1. StrangeStar or NeutronStarEoS & Current Observation Reporter: Long Jiang Nanjing University 2013 05 27

2. Outline • Introduction Why SQS Structure difference between NS and SQS • Equation of State MIT bag model Density dependent model by Dey • Models discussion and my present work Candidates of SQS My recent work

3. Introduction • SQM stable than nuclei ~10^15 g/cm^3

4. Structure description Equation of State: p=? R. R. Silbar, S. Reddy, 2004, Am. J. Phys. 72,892

5. EoS -1: MIT bag Model • Consider quark-gluon coupling: • Massless-quark without Q-G coupling: Chapline &Nauenberg 1977, Phys.Rev.D16,450

6. EoS-2: Density dependent: Dey Part 1. Density dependent quark mass: M. Dey et al. Phys.Lett.B438, 123(1998)

7. Part 2.Interquark potential: Pair creation & infrared divergence -- Screening length: J. L. Richardson, Phys.Lett.B 82(1979)272

8. Screening length • Simplify with: V. Baluni Phys. Rev. D17(1978) 2092

9. Conditions • β-equilibrium • Charge neutrality:

10. Chemical potential

11. Parameters T. Gangopadhyay et al.arXiv:1303.1956

12. Present Observation D. Leahy et al. ApJ 672, 1119(2008) S. Guillot et al. arXiv: 1302.0023

13. a c b Data-Model consistence analysis 天文数据处理方法 P133

14. Example of model-Fitting

15. Some results as examples

16. Thank you !!