Abstract
With the explosion of multi-messenger astronomy, being able to theoretically model neutron stars is crucial to make sense of new and improved data. We present an extensible neutron star code which can be used to study a neutron star for different structure equations, equation of states and rotational perturbations. The code is unit tested where applicable, ensuring that the code will produce correct results. We perform an initial application of the code, by modelling a rotating neutron star using the Hartle-Thornes slow rotation approximation and study the neutron stars thermal evolution through an in-house cooling model developed by Jakob Borg. The cooling scenario chosen investigates only the direct Urca (DURCA) process, modified Urca (MURCA) process and thermal radiation. Furthermore, we test the requirement for general relativistic correction by comparing the Newtonian and Tolman-Oppenheimer-Volkoff (TOV) equations and study the different parametrisations BSk19, BSk20 and BSk21 of the Brussels-Montreal unified crust-core equation of state. We find that the BSk21 is the only sufficient parametrisation for the Brussels-Montreal model for the TOV equation. In addition, we find rotation is an important aspect to consider in thermal evolution of fast rotators (⪆1000 rad/s=159 Hz) and that thermal evolution is dependent on the latitudinal position.
Supervisors:
Professor Øystein Elgarøy, Institute of Theoretical Astrophysics, UiO
Associate Professor Hans Arnold Winther, Institute of Theoretical Astrophysics, UiO
Intern. assessor: Professor Per Barth Lilje, Institute of Theoretical Astrophysics, UiO
Extern. assessor: Professor José Beltrán Jiménez, University of Salamanca