Thesis

Effect of strong magnetic fields on transport coefficients

• Call:

  IDPASC Portugal - PHD Programme 2017

• Academic Year:

  2017 / 2018

• Domains:

  Theoretical Particle Physics | Astrophysics

• Supervisor:

  Constança Providência

• Co-Supervisor:

  Pedro Costa

• Institution:

  Universidade de Coimbra

• Host Institution:

  CFisUC

• Abstract:

  The heat, charge and momentum transport coefficients are essential to model the star evolution, the rotational dynamics or the electromagnetic and gravitational wave emission, but also to model heavy ion collisions. When very strong magnetic fields are considered, transport properties become anisotropic. The calculation of transport coefficients on the neutron star crust has been previously undertaken by many authors [Chamel08] for non-magnetized stars, using solid state physics methods [Ziman60]. The main carriers of charge in the crust are the electrons and the contributions from the scattering of electrons on electrons, protons and ions is expected to contribute to the conductivity. In magnetized stars, the electrical conductivity is an input in the dissipative magneto-hydrodynamics simulations. In heavy ion collisions transport codes need as inputs shear and bulk viscosities of quark and hadronic matter. Besides they can also indicate the location of a phase transition in the phase diagram. There have been several works on electron conduction along quantizing magnetic fields in neutron star envelopes and outer crusts [Potekhin99]. Recently, these works were generalised to warm matter with 10^9 We will consider the case of strongly degenerate particles and we will assume quantizing magnetic fields. The collision term, which we will treat in the relaxation time approximation, will be added to the Vlasov equation, in order to calculate the transport properties ([Laundau81], [Heiselberg93]). A variational formulation of transport theory is needed to treat the electromagnetic interaction due to ist singularity [Heiselberg93]. A small temperature or charge chemical potential variation will give rise to a perturbation of the distribution function. The moment relaxation time will be determined, followed by the calculation of the transverse and longitudinal electric and thermal conductivities as well as the viscosity. We will provide accurate fits of the calculated transport coefficients. Chamel08 - Nicolas Chamel and Pawel Haensel, Living Rev. Relativ. 11, 10 (2008). Harutyunyan16 - Arus Harutyunyan and Armen Sedrakian, Phys. Rev. C 94, 025805 (2016). Potekhin99 - A. Y. Potekhin, Astron. and Astrophys. 351, 787 (1999). Ziman60 - J. M. Ziman, Electrons and phonons, Oxford University Press Landau81 - L.P. Pitaevskii; E.M. Lifshitz (1981). Physical Kinetics. Vol. 10 (1st ed.). Pergamon Press. Heiselberg93 - H. Heiselberg and C J Pethick, Phys. Rev. D 48, 2916 (1993)