Geodesic
Strange stars at vacuum pressure dependent on quark density
Proceedings of the Yerevan State University. Physical and mathematical sciences, Tome 51 (2017) no. 1, pp. 71-76.

Voir la notice de l'article provenant de la source Math-Net.Ru

Equation of state of strange quark matter has been studied in the framework of MIT bag model, when vacuum pressure B depends on concentration of baryons $n$. The actuality of such studies is conditioned by the increasing of quark matter density from surface to star center. In the literature there exist different representations of function $B(n)$. In the present work Gaussian parametrization is used, which is based on the idea of existence of asymptotic limiting value of this parameter. For four groups of parameters the equations of state of quark matter were determined. The main integral parameters of star configurations were obtained by numerically integrating of star equilibrium equations (the TOV equation). In the considered case it turns that when vacuum pressure dependence on concentration of baryons is taken into account, configurations of strange stars have maximal masses less than two solar masses.
Keywords: strange stars, strange quark matter, vacuum variable pressure. 
@article{UZERU_2017_51_1_a12,
     author = {Yu. L. Vardanyan and A. K. Grigoryan and H. A. Shahinyan},
     title = {Strange stars at vacuum pressure dependent on quark density},
     journal = {Proceedings of the Yerevan State University. Physical and mathematical sciences},
     pages = {71--76},
     publisher = {mathdoc},
     volume = {51},
     number = {1},
     year = {2017},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/UZERU_2017_51_1_a12/}
}
TY  - JOUR
AU  - Yu. L. Vardanyan
AU  - A. K. Grigoryan
AU  - H. A. Shahinyan
TI  - Strange stars at vacuum pressure dependent on quark density
JO  - Proceedings of the Yerevan State University. Physical and mathematical sciences
PY  - 2017
SP  - 71
EP  - 76
VL  - 51
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/UZERU_2017_51_1_a12/
LA  - en
ID  - UZERU_2017_51_1_a12
ER  - 
%0 Journal Article
%A Yu. L. Vardanyan
%A A. K. Grigoryan
%A H. A. Shahinyan
%T Strange stars at vacuum pressure dependent on quark density
%J Proceedings of the Yerevan State University. Physical and mathematical sciences
%D 2017
%P 71-76
%V 51
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/UZERU_2017_51_1_a12/
%G en
%F UZERU_2017_51_1_a12
Yu. L. Vardanyan; A. K. Grigoryan; H. A. Shahinyan. Strange stars at vacuum pressure dependent on quark density. Proceedings of the Yerevan State University. Physical and mathematical sciences, Tome 51 (2017) no. 1, pp. 71-76. http://geodesic.mathdoc.fr/item/UZERU_2017_51_1_a12/

[1] M. Buballa, “NJL-Model Analysis of Dense Quark Matter”, Physics Reports, 407 (2005), 205–376 | DOI

[2] Y. Nambu, G. Jona-Lasinio, “Dinamical Model of Elementary Particles Based on an Analogy with Superconductivity”, Physical Review, 122 (1961), 345–358 | DOI | MR

[3] Y. Nambu, G. Jona-Lasinio, “Dinamical Model of Elementary Particles Based on an Analogy with Superconductivity. II”, Physical Review, 124 (1962), 246–254 | DOI | MR

[4] A. Chodos, R.L. Jaffe, K. Johnson, C.B. Thorne, V.F. Weisskopf, “A New Extended Model of Hadrons”, Phys. Rev. D, 9 (1974), 3471 | DOI | MR

[5] A. Chodos, R.L. Jaffe, K. Johnson, C.B. Thorne, “Baryon Structure in the Bag Theory”, Phys. Rev. D, 10 (1974), 2599 | DOI

[6] S. Chakrabarty, S. Raha, B. Sinha, “Strange Quark Matter and the Mechanism”, Phys. Lett. B, 113 (1989), 229 | DOI

[7] O.G. Benvenuto, G. Lugones, “Strange Matter Equation of State in the Quark Mass-Density Dependent Model”, Phys. Rev. D, 51 (1995), 1989–1993 | DOI

[8] N. Itoh, “Hydrostatic Equilibrium of Hypothetical Quark Stars”, Prog. Theor. Phys., 44 (1970), 291 | DOI

[9] G. Baym, S. Chin, Can a Neutron Star be a Giant MIT Bag?, Phys. Lett. B, 62 (1976), 241 | DOI

[10] G.B. Alaverdyan, A.R.Harutyunyan, Yu.L. Vartanyan, “Neutron Stars with a Quark Core. I: Equations of State”, Astrophysics, 46 (2003), 361 | DOI

[11] G.B. Alaverdyan, A.R.Harutyunyan, Yu.L. Vartanyan, “Neutron Stars with a Quark Core. II: Basic Integral and Structural Parameters”, Astrophysics, 47 (2004), 52 | DOI

[12] Y.L. Vardanyan, A.K. Grigoryan, H.A. Shahinyan, “Maximal Mass of Strange Stars and Pulsarswith More Precisely Measured Masses”, Astrophysics, 58 (2015), 297–310

[13] Y.L. Vardanyan, A.K. Grigoryan, H.A. Shahinyan, “Pulsar PSR J0348-0432 and Strange Stars”, Letters in Astronom. Journal, 41 (2015), 1–8 | DOI

[14] G.F. Burgio, M. Baldo, P.K.Sahu, H.-J. Schulze, “Hadron-Quark Phase Transition in Dense Matter and Neutron Stars”, Phys. Rev. C., 66 (2002), 25802 | DOI

[15] A.R. Bodmer, “Collapsed Nuclei”, Phys. Rev. D, 4 (1971), 1601 | DOI

[16] H. Terazawa, “INS-Report-338. ( INS Univ. of Tokyo, 1979)”, J. Phys Soc. Of Japan, 58 (1989), 3555 | DOI

[17] E. Witten, “Cosmic Separation of Phases.”, Phys. Rev. D, 30 (1984), 272 | DOI

[18] R.L. Jaffe, E. Farhi, “Strange Matter”, Phys. Rev. D, 30 (1984), 2379 | DOI

[19] C. Alcock, A. Olinto, “Exotic Phases of Hadronic Matter and Their Astrophysical Application”, Ann. Rev. Nucl. Part. Sci., 38 (1988), 161–184 | DOI

[20] O.G. Benvenuto, J.E. Horvarth, H. Vucetich, “Strange-Pulsar Models”, Intern. J. of Modern Phys., A6 (27) (1991), 4769–4830 | DOI

[21] C. Adami, G.E. Brown, “Matter Under Extreme Conditions”, Phys. Rep., 234 (1993), 1–71 | DOI

[22] G.F. Burgio, M. Baldo, P.K. Sahu, A.B. Santra, H.-J. Schulze, “Maximum Mass of Neutron Stars with a Quark Core”, Phys. Lett. B., 526 (2002), 19–26 | DOI

[23] M.F. Zhu, G.Z. Liu, Z. Yu, Y. Xu, W.T. Song, “Thermodynamics of Strange Quark Matter with the Density-Dependent Bag Constant”, Science in China Series G, 52:10 (2009), 1506–1512 | DOI

[24] R.C. Tolman, “Static Solutions of Einstain’s Field Equations for Spheres of Fluid”, Phys. Rev., 55 (1939), 364 | DOI

[25] J.R. Oppenheimer, G.M. Volkoff, “On Massive Neutron Cores”, Phys. Rev., 55 (1939), 374 | DOI | Zbl

[26] Yu.L. Vartanyan, “Superdense Stars Containinig Strange Baryons”, Astrophysics, 53 (2010), 18 | DOI

[27] J. Antoniadis, P.C. Freire et al., “A Massive Pulsar in a Compact Relativistic Binary”, Science, 340 (2013), 1233232 | DOI

[28] P. Demorest, T. Pennucci, S.M. Ransom, M.S.E. Roberts, J.W.T. Hessels, “A Two-Solar-Mass Neutron Star Measured Using Shapiro Delay”, Nature, 467 (2010), 1081 | DOI

[29] G.F. Burgio, M. Baldo, H. Chen, H.-J. Schulze, “The Equation of State at Finite Temperature: Structure and Composition of Protoneutron Stars”, J. Phys. Conf. Ser., 665 (2016), 012062 | DOI