Observational Properties Of Strange Star Containing Dark Matter

Along with the increasing number of Pulsars(PSR)detected by the Chinese Eye--FAST and recently observed giant mass Pulsar in the world,attention to the properties of the stars is soaring.Being known as fast rotating PSR,neutron star's high density and complex phase structure are beyond prediction.However,whether a neutron star is a traditional neutron star,a Hyperon star or a strange star,has not conclusion.There exist deconfined quark matter phase or deeply concerned dark matter in its high density core,is still an Enigma.The following studies on strange quark stars will be down in order to provide theoretical reference for high density matter physics,to give out theoretical evidence for astronomic observation and distinguish of the detected PSR,to study properties of dark matter indirect manner.In the first chapter,the history and current situations of neutron star investigation.Are briefly discussed.Short introductions on the traditional neutron star,a Hyperon star and a strange star are given,then several models for describing strange quark matter are introduced respectively.Strange star containing dark matter is studied in the second chapter.The strange quark matter is described by bag model with density-dependant bag parameter and the thermodynamically self-consistent treatment is made to strange quark matter thermodynamics.Begins with a brief introduction to the history of dark matter research,in this chapter,the equation of state(EOS)for strange quark matter containing strong and weak interaction dark matter is calculated.Using EOS as the input,the TOV equation is solved,the mass-radius relationship of the strange star,and other surface observational properties of the neutron star(for example,the gravitational red-shift,rotation period,moment of inertia)are given.Here,we take the dark matter particle mass as 0.1GeV,0.3GeV and 0.5GeV.Our results show that both weakly or strong interactions,dark matters soften the EOS.The bigger dark matter particle mass,the softer EOS,the smaller strange star mass.Results also show that strange star mass is smaller than the lower limit of the observational data when dark particle mass bigger than 0.3GeV.These indicate that the both strongly and weakly interacting dark matter its particle mass smaller than 0.3GeV maybe contained in strange stars.Comparing strong and weak interactions,one find that mass of strange stars contain weakly interacting dark matter slightly bigger than those of the strongly interacting case when dark particle mass are same.The differences become smaller with the decrease of the dark particle mass.In the third chapter,the influences of gravitation correction caused by the introduction of U Boson on the global observation properties of the strange quark star are studied.Here the strange quark matter is described by the thermodynamically self-consistent quark model.Firstly,a brief introduction to the theory of gravity correction is given.Secondly,the influences of coupling strength for U-Boson on the EOS,thus on masses and radii and the other surface observation properties of hybrid stars are investigated.Results indicate that with the increase of the U-Boson coupling constant,the EOS is stiffen,the mass of the strange stars is obviously increased.These results overcomes the difficulties for the week EOS cannot describe the neutron stars with giant mass.The results imply that the recently observed giant mass Pulsar,PSR J1614-2230 and PSR J1614-2230,can be a strange star with strong U-Boson coupling.The properties of the strange stars contain dark matter and gravitation correction are studied in the last chapter.The quark matter is described by the thermodynamically self-consistent quark model.Our results indicate that,no matter dark matter contained in the strange stars or not,gravitation correction harden the EOS and increase the mass of the stars.The results further infer that the recently observed giant mass Pulsars can be a strange star containing weakly interacting dark matters and suitable to described by corrected gravitation theory.Comparing calculation results and the observation data,one know that the weakly interacting dark matters,with particle mass smaller than 0.3 GeV,maybe mixed in the strange quark stars.