We present a modified version of quark mass scaling via considering the important one-gluonexchange interaction between quarks in the quark mass density-dependent model. The properties of strange quark matter and the ...We present a modified version of quark mass scaling via considering the important one-gluonexchange interaction between quarks in the quark mass density-dependent model. The properties of strange quark matter and the structure of strange stars are then studied with the new scaling and a self-consistent thermodynamic treatment. It is found that the one-gluon-exchange effect lowers the system energy considerably, makes the equation of state stiffer, and the sound velocity tends to the ultra-relativistic value faster, which make the biggest value of the maximum mass of strange stars become as big as approximately 2 times the solar mass, in accordance with the latest astronomical observations.展开更多
The attempt has been taken to calculate the density of stars possessing quark matter core using sphere packing concept of crystallography. The quark matter has been taken as solid in nature as predicted in references ...The attempt has been taken to calculate the density of stars possessing quark matter core using sphere packing concept of crystallography. The quark matter has been taken as solid in nature as predicted in references 36 and 37, and due to immense gravitational pressure at the core of the star the densest packing of quarks as spheres has been assumed to calculate the packing fraction Φ, thus the density ρ of the matter. Three possible types of pickings—mono-sized sphere packing, binary sphere packing and ternary sphere packing, have been worked out using three possible types of quark matter. It has been concluded that no value about the ρ of quark matter can be calculated using binary and ternary packing conditions and for mono-sized packing condition different flavor quark matters of different values in the density have been calculated using results from the experiments done by HI, ZEUS, L3 and CDF Collaborations about the radius limit of quark. For example, for u quark matter ρ ranges from 4.0587 × 1048 - 7.40038 × 1048 MeV/c2 cm3 using results of L3 Collaboration, for s quark matter 15.91794 × 1048 - 17.6866 × 1048 MeV/c2 cm3, etc.展开更多
Quarks are proposed to be grouped together to make quark-clusters due to the strong interaction in cold quark matter at a few nuclear densities,because a weakly coupling treatment of the interaction between quarks the...Quarks are proposed to be grouped together to make quark-clusters due to the strong interaction in cold quark matter at a few nuclear densities,because a weakly coupling treatment of the interaction between quarks there would be inadequate.Cold quark matter is then conjectured to be in solid state (i.e.,forming a crystal structure) if the inter-cluster potential is deep enough to localize clusters in lattice.Such a solid state of cold quark matter would be very necessary for us to understand different manifestations of pulsar-like compact stars,and could not be ruled by first principles.展开更多
We study the properties of two-flavor quark matter in the Dyson-Schwinger model and investigate the possible consequences for hybrid neutron stars,with particular regard to the two-solar-mass limit.We find that with s...We study the properties of two-flavor quark matter in the Dyson-Schwinger model and investigate the possible consequences for hybrid neutron stars,with particular regard to the two-solar-mass limit.We find that with some extreme values of the model parameters,the mass fraction of two-flavor quark matter in heavy neutron stars can be as high as 30 percent and the possible energy release during the conversion from nucleonic neutron stars to hybrid stars can reach 1052 erg.展开更多
We study the properties of two-flavor quark matter in the equivparticle model.A new quark mass scaling at finite temperature is proposed and applied to the thermodynamics of two-flavor quark matter.It is found that th...We study the properties of two-flavor quark matter in the equivparticle model.A new quark mass scaling at finite temperature is proposed and applied to the thermodynamics of two-flavor quark matter.It is found that the perturbative interaction has strong effect on quark matter properties at finite temperature and high density.The pressure at the minimum free energy per baryon is exactly zero.With increasing temperature,the energy per baryon increases,while the free energy per baryon decreases.展开更多
I investigate the ferromagnetic phase transition inside strong quark matter (SQM) with one gluon exchange interaction between strong quarks. I use a variational method and the Landau-Fermi liquid theory and obtain the...I investigate the ferromagnetic phase transition inside strong quark matter (SQM) with one gluon exchange interaction between strong quarks. I use a variational method and the Landau-Fermi liquid theory and obtain the thermodynamics quantities of SQM. In the low temperature limit, the equation of state (EOS) and critical exponents for the second-order phase transition (ferromagnetic phase transition) in SQM are analytically calculated. The results are in agreement with the Ginzberg-Landau theory.展开更多
We investigate the properties of strange quark matter (SQM) in a strong magnetic field with quark confinement by the density dependence of quark masses considering the total baryon number conservation, charge neutra...We investigate the properties of strange quark matter (SQM) in a strong magnetic field with quark confinement by the density dependence of quark masses considering the total baryon number conservation, charge neutrality and chemical equilibrium. It is found that an additional term should appear in the pressure expression to maintain thermodynamic consistency. At fixed density, the energy density of magnetized SQM varies with the magnetic field strength. By increasing the field strength an energy minimum exists located at about 6×10^19 Gauss when the density is fixed at two times the normal nuclear saturation density.展开更多
The diquark condensate susceptibility in neutral colour superconductor at moderate baryon density is calculated in the frame of the two-flavour Nambu-Jona-Lasinio model with the mean field approximation. When colour c...The diquark condensate susceptibility in neutral colour superconductor at moderate baryon density is calculated in the frame of the two-flavour Nambu-Jona-Lasinio model with the mean field approximation. When colour chemical potential is introduced to keep charge neutrality, the dlquark condensate susceptibility & negative in the directions without diquark condensate in colour space, which may be regarded as a signal of the instability of the conventional ground state with only diquark condensate in the colour-3 direction.展开更多
We have constructed cosmological models for string cloud and domain walls coupled with quark matter in Lyra geometry. For this purpose we have solved the field equations using anisotropy feature of the universe, speci...We have constructed cosmological models for string cloud and domain walls coupled with quark matter in Lyra geometry. For this purpose we have solved the field equations using anisotropy feature of the universe, special law of variation for Hubble’s parameter proposed by Berman [78] which yields constant deceleration parameter;and time varying displacement field . Further some properties of the obtained solutions are discussed.展开更多
基金Supported by National Natural Science Foundation of China (11135011, 11045006)Key Project from Chinese Academy of Sciences (Y12A0A0012)
文摘We present a modified version of quark mass scaling via considering the important one-gluonexchange interaction between quarks in the quark mass density-dependent model. The properties of strange quark matter and the structure of strange stars are then studied with the new scaling and a self-consistent thermodynamic treatment. It is found that the one-gluon-exchange effect lowers the system energy considerably, makes the equation of state stiffer, and the sound velocity tends to the ultra-relativistic value faster, which make the biggest value of the maximum mass of strange stars become as big as approximately 2 times the solar mass, in accordance with the latest astronomical observations.
文摘The attempt has been taken to calculate the density of stars possessing quark matter core using sphere packing concept of crystallography. The quark matter has been taken as solid in nature as predicted in references 36 and 37, and due to immense gravitational pressure at the core of the star the densest packing of quarks as spheres has been assumed to calculate the packing fraction Φ, thus the density ρ of the matter. Three possible types of pickings—mono-sized sphere packing, binary sphere packing and ternary sphere packing, have been worked out using three possible types of quark matter. It has been concluded that no value about the ρ of quark matter can be calculated using binary and ternary packing conditions and for mono-sized packing condition different flavor quark matters of different values in the density have been calculated using results from the experiments done by HI, ZEUS, L3 and CDF Collaborations about the radius limit of quark. For example, for u quark matter ρ ranges from 4.0587 × 1048 - 7.40038 × 1048 MeV/c2 cm3 using results of L3 Collaboration, for s quark matter 15.91794 × 1048 - 17.6866 × 1048 MeV/c2 cm3, etc.
基金Supported by NSFC (10778611,10973002)National Basic Research Program of China (2009CB824800) and LCWR (LHXZ200602)
文摘Quarks are proposed to be grouped together to make quark-clusters due to the strong interaction in cold quark matter at a few nuclear densities,because a weakly coupling treatment of the interaction between quarks there would be inadequate.Cold quark matter is then conjectured to be in solid state (i.e.,forming a crystal structure) if the inter-cluster potential is deep enough to localize clusters in lattice.Such a solid state of cold quark matter would be very necessary for us to understand different manifestations of pulsar-like compact stars,and could not be ruled by first principles.
基金Supported by NSFC(11305144,11475149,11303023)Central Universities(CUGL 140609)in China"NewCompStar,"COST Action MP1304
文摘We study the properties of two-flavor quark matter in the Dyson-Schwinger model and investigate the possible consequences for hybrid neutron stars,with particular regard to the two-solar-mass limit.We find that with some extreme values of the model parameters,the mass fraction of two-flavor quark matter in heavy neutron stars can be as high as 30 percent and the possible energy release during the conversion from nucleonic neutron stars to hybrid stars can reach 1052 erg.
基金supported by the National Natural Science Foundation of China(Nos.11135011,11475110,and 11575190)the CAS Present’s International Fellowship Initiative(Nos.2015PM008 and2016VMA063)
文摘We study the properties of two-flavor quark matter in the equivparticle model.A new quark mass scaling at finite temperature is proposed and applied to the thermodynamics of two-flavor quark matter.It is found that the perturbative interaction has strong effect on quark matter properties at finite temperature and high density.The pressure at the minimum free energy per baryon is exactly zero.With increasing temperature,the energy per baryon increases,while the free energy per baryon decreases.
文摘I investigate the ferromagnetic phase transition inside strong quark matter (SQM) with one gluon exchange interaction between strong quarks. I use a variational method and the Landau-Fermi liquid theory and obtain the thermodynamics quantities of SQM. In the low temperature limit, the equation of state (EOS) and critical exponents for the second-order phase transition (ferromagnetic phase transition) in SQM are analytically calculated. The results are in agreement with the Ginzberg-Landau theory.
基金Supported by National Natural Science Foundation of China(11135011,11475110)CAS Key Project(KJCX3-SYW-N2)
文摘We investigate the properties of strange quark matter (SQM) in a strong magnetic field with quark confinement by the density dependence of quark masses considering the total baryon number conservation, charge neutrality and chemical equilibrium. It is found that an additional term should appear in the pressure expression to maintain thermodynamic consistency. At fixed density, the energy density of magnetized SQM varies with the magnetic field strength. By increasing the field strength an energy minimum exists located at about 6×10^19 Gauss when the density is fixed at two times the normal nuclear saturation density.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10428510, 10435080, 10447122 and 10575058, and the Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP) under Grant No 20040003103.
文摘The diquark condensate susceptibility in neutral colour superconductor at moderate baryon density is calculated in the frame of the two-flavour Nambu-Jona-Lasinio model with the mean field approximation. When colour chemical potential is introduced to keep charge neutrality, the dlquark condensate susceptibility & negative in the directions without diquark condensate in colour space, which may be regarded as a signal of the instability of the conventional ground state with only diquark condensate in the colour-3 direction.
文摘We have constructed cosmological models for string cloud and domain walls coupled with quark matter in Lyra geometry. For this purpose we have solved the field equations using anisotropy feature of the universe, special law of variation for Hubble’s parameter proposed by Berman [78] which yields constant deceleration parameter;and time varying displacement field . Further some properties of the obtained solutions are discussed.
基金National Basic Research Program of China(973 Program)(2013CB834405,2015CB856904)National Natural Science Foundation of China(11625521,11275125,11135011)+2 种基金Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher LearningKey Laboratory for Particle Physics,Astrophysics and Cosmology,Ministry of Education,ChinaProgram of Science and Technology Commission of Shanghai Municipality(11DZ2260700)~~