Thesis

Properties of the Compact Astrophysical Objects Constrained by the Nuclear Physics, Astrophysics and Gravitational Wave Physics Data

• Call:

  IDPASC Portugal - PHD Programme 2019

• Academic Year:

  2019 / 2020

• Domains:

  Theoretical Particle Physics | Astrophysics

• Supervisor:

  Violetta Sagun

• Co-Supervisor:

  Ilidio Lopes

• Institution:

  Universidade de Coimbra

• Host Institution:

  CENTRA, Instituto Superior Técnico / CFisUC, Universidade de Coimbra

• Abstract:

  The compact astrophysical objects, i.e. neutron stars (NSs), hypothetical hybrid (HS) and quark stars (QSs), are the most dense physical objects accessible by the direct observations. The 2017 Nobel Prize in Physics for detection of gravitational waves (GWs) in merger of black holes along with consequent detection of the NSs merger illustrates an importance of this hot topic. Despite the flourishing of astrophysical observations, the particle composition of the interior of compact stars is still very poorly known. Moreover, the physical processes inside hypothetical objects like HSs and QSs, for which is expected that matter goes through a phase transition from nuclear matter to a plasma of strongly interacting quarks, are also very poorly understood. Particularly, this limitation comes from the fact that QCD and its lattice formulation have very limited applicability at large baryonic densities and as such does not allow to obtain a reliable equation of state (EoS). Detection of QS or HS can become another scientific breakthrough and prove existence of quark matter, which is the main quest of largest research collaborations, such as ALICE at the Large Hadron Collider (LHC) in CERN. This thesis will pursue two goals: (i) development of a realistic quark-hadron EoS which is consistent with known properties of nuclear matter, experimental data on nuclear-nuclear collisions and observational data on compact stars and merger of binary system GW170817; (ii) application of the formulated EoS to the modelling of compact stars` evolution, while at non-vanishing temperatures it will be applied to the NSs mergers and prediction the GW waveforms. The selected candidate will establish a solid bridge between experimental and theoretical astrophysics, gravitation and nuclear physics. The thesis will be supervised by Violetta Sagun, theoretical physicist, in Coimbra and Ilídio Lopes, an expert in astrophysics and cosmology, in Lisbon.