Thesis (M. Phil.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves [168]-173).

Thesis (M. Phil.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf [74]-81).

Thesis (Ph.D.)--Old Dominion University, 2004.

Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics. / Includes bibliographical references. Also available on the Internet.

No description available.

A new method for generating initial data for simulations of neutron stars in binary systems. The construction of physically relevant initial data is crucial to accurate assessment of gravitational wave signals relative to theoretical predictions. This method builds upon the Bowen-York curvature for puncture black holes. This data is evolved and compared against simulations in the literature with respect to orbital eccentricity, merger and collapse times, and emitted energy and angular momentum. The data exhibits some defects, including large central density oscillations in stars and center of mass drift in unequal-mass systems. Some approaches for improvements in potential future work are discussed.

published_or_final_version / Physics / Doctoral / Doctor of Philosophy

We present the results of fully three dimensional, post-Newtonian hydrodynamical simulations of the dynamical evolution of mergers between compact stellar remnants (neutron stars and black holes). Although the code is essentially Newtonian, we simulate gravitational wave emission and the corresponding effect on the fluid flow via a post-Newtonian correction. Also, we use a modified Newtonian potential which reproduces certain aspects of the Schwarzschild and Kerr solutions to improve the physics in the vicinity of the black hole. Changes to the energy by neutrino/antineutrino emission are accounted for by an extensive neutrino leakage scheme. The hydrodynamical equations are integrated using the piecewise parabolic method (PPM) and the neutron star matter is described by a tabulated equation of state (EoS). Since the physics of matter at the extreme densities found in neutron stars is not yet certain, we compare results computed using two such tables to ascertain whether this uncertainty in the micro-physics extends to an uncertainty in the energy available to power a short-period gamma-ray burst. With an aim to including magnetic field physics to these simulations, we present a survey of approximate Riemann solvers which may be more easily extended to the system of equations of magnetohydrodynamics (MHD) than the exact or iterative Riemann solver used in the PPM scheme. Tests are performed using the linearised solver of Roe and the approximate Harten, Lax, van Leer and Einfeldt Riemann solvers (HLLE and HLLEM) with the PPM reconstruction scheme. Finally, we discuss the effectiveness of these approximate Riemann solvers in the simulation of mergers between compact stellar remnants.

Yeung Yuk Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 82-85). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivations --- p.1 / Chapter 1.2 --- Historical background --- p.2 / Chapter 1.3 --- Outline of this thesis --- p.3 / Chapter 2 --- Mode classifications --- p.5 / Chapter 2.1 --- Fluid modes --- p.6 / Chapter 2.1.1 --- f mode (fundamental mode) --- p.6 / Chapter 2.1.2 --- p mode (pressure mode) --- p.7 / Chapter 2.1.3 --- g mode (gravity mode) --- p.7 / Chapter 2.2 --- w mode (spacetime mode) --- p.8 / Chapter 3 --- Oscillations of neutron stars --- p.10 / Chapter 3.1 --- The equilibrium configurations of neutron star models --- p.10 / Chapter 3.1.1 --- Newtonian stars --- p.10 / Chapter 3.1.2 --- Relativistic stars --- p.11 / Chapter 3.2 --- Perturbation of the star's equilibrium --- p.14 / Chapter 3.2.1 --- Axial perturbation equation --- p.15 / Chapter 3.2.2 --- Boundary conditions --- p.16 / Chapter 3.2.3 --- Numerical techniques --- p.16 / Chapter 3.2.4 --- The Quasinormal modes of stars --- p.18 / Chapter 4 --- Excitation and detection of QNMs --- p.20 / Chapter 4.1 --- Studies of excitation of stellar QNMs --- p.20 / Chapter 4.2 --- Detection of QNM ringing --- p.21 / Chapter 4.3 --- Parameter estimation --- p.23 / Chapter 5 --- Oscillations of realistic neutron stars --- p.28 / Chapter 5.1 --- Motivations of study --- p.28 / Chapter 5.2 --- Realistic equations of state --- p.29 / Chapter 5.3 --- Axial QNM --- p.36 / Chapter 6 --- Logarithmic perturbation method --- p.38 / Chapter 6.1 --- Introduction --- p.38 / Chapter 6.2 --- Logarithmic perturbation theory --- p.39 / Chapter 6.3 --- Evaluation of perturbation formulae --- p.42 / Chapter 6.3.1 --- The first-order perturbation --- p.42 / Chapter 6.3.2 --- The second-order perturbation --- p.47 / Chapter 6.4 --- Comparison of LPT calculations with exact results --- p.47 / Chapter 6.5 --- Discussion --- p.51 / Chapter 7 --- Scaled coordinate logarithmic perturbation method --- p.53 / Chapter 7.1 --- Rescaling of the axial perturbation equations --- p.54 / Chapter 7.1.1 --- The original axial perturbation equations --- p.55 / Chapter 7.1.2 --- The rescaled axial perturbation equations --- p.56 / Chapter 7.2 --- The formalism of SCLPT --- p.57 / Chapter 7.2.1 --- Logarithmic perturbation theory --- p.59 / Chapter 7.2.2 --- First-order perturbation --- p.63 / Chapter 7.2.3 --- Second-order perturbation --- p.65 / Chapter 7.3 --- Comparison of the perturbation calculation with the exact result --- p.67 / Chapter 7.4 --- Discussion --- p.70 / Chapter 8 --- Conclusion --- p.73 / Chapter 8.1 --- Summary --- p.73 / Chapter 8.2 --- Outlook --- p.74 / Chapter A --- Units conventions --- p.76 / Chapter B --- Numerical technique in Leaver's series --- p.77 / Chapter C --- Method of numerical derivatives --- p.80 / Bibliography --- p.82

Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics, August 2000. / Includes bibliographical references. Also available on the Internet.