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by Lin Lap-Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves [105]-109). / Text in English; abstracts in English and Chinese. / by Lin Lap-Ming. / Abstract --- p.i / Acknowledgement --- p.ii / Contents --- p.iii / List of Figures --- p.vi / List of Tables --- p.ix / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Physical Motivation --- p.1 / Chapter 1.2 --- Quasi-Normal Modes --- p.3 / Chapter 1.3 --- Superfluidity in Neutron Stars --- p.7 / Chapter 1.4 --- Outline of this Thesis --- p.9 / Chapter Chapter 2. --- The Ordinary Perfect Fluid Neutron Stars --- p.11 / Chapter 2.1 --- The Equilibrium Neutron Star Models --- p.11 / Chapter 2.2 --- Non-Radial Oscillations of Neutron Stars --- p.14 / Chapter 2.3 --- The Quasi-Normal Modes of Stars --- p.17 / Chapter 2.3.1 --- The Fluid Modes --- p.17 / Chapter 2.3.2 --- The Spacetime Modes --- p.18 / Chapter Chapter 3. --- The General Relativistic Superfluid Formalism --- p.22 / Chapter 3.1 --- The Carter Formalism --- p.22 / Chapter 3.2 --- The Master Function --- p.25 / Chapter Chapter 4. --- The Equilibrium Superfluid Neutron Stars --- p.27 / Chapter 4.1 --- The Equilibrium Configurations --- p.27 / Chapter 4.2 --- Initial and Boundary Conditions --- p.34 / Chapter 4.3 --- Polytropic Models --- p.36 / Chapter Chapter 5. --- Non-Radial Oscillations of Superfluid Neutron Stars --- p.40 / Chapter 5.1 --- The Linearized Field Equations Inside the Star --- p.40 / Chapter 5.1.1 --- Equations for Even-Parity Perturbations --- p.45 / Chapter 5.1.2 --- Equations for Odd-Parity Perturbations --- p.48 / Chapter 5.2 --- Initial and Boundary Conditions --- p.49 / Chapter 5.2.1 --- Radial Integration Initial Conditions --- p.49 / Chapter 5.2.2 --- Boundary conditions at the Surface --- p.55 / Chapter 5.3 --- The Linearized Field Equations Outside the Star --- p.57 / Chapter 5.4 --- Numerical Technique --- p.60 / Chapter Chapter 6. --- Quasi-Normal Modes Extraction --- p.62 / Chapter 6.1 --- Numerical Techniques for Quasi-Normal Modes Extraction --- p.62 / Chapter 6.2 --- The Leaver Series --- p.64 / Chapter 6.3 --- The Graphical Method --- p.67 / Chapter Chapter 7. --- The Quasi-Normal Modes of Superfluid Neutron Stars --- p.69 / Chapter 7.1 --- Polytropic Models --- p.69 / Chapter 7.1.1 --- The w-modes --- p.70 / Chapter 7.1.2 --- The f- and p-modes --- p.74 / Chapter 7.2 --- Ideal Neutron-Proton-Electron Gas --- p.82 / Chapter 7.3 --- Convergence Tests and Accuracy --- p.92 / Chapter Chapter 8. --- Conclusion --- p.95 / Appendix A. Speeds of Sound --- p.97 / Appendix B. Equations for Radial Oscillations --- p.99 / Appendix C. Numerical Technique for Solving Leaver's Series --- p.101 / Appendix D. Scaling in Numerical Calculations --- p.103 / Bibliography --- p.105

Wong, Ka Sin Jamie = 超流性對中子星振盪的影響 / 黃家倩. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (p. 212-215). / Abstract also in Chinese. / Wong, Ka Sin Jamie = Chao liu xing dui zhong zi xing zhen dang de ying xiang / Huang Jiaqian. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Motivations --- p.1 / Chapter 1.2 --- Outline of Thesis --- p.3 / Chapter 1.3 --- Notation and Conventions --- p.4 / Chapter 2 --- The Relativistic Superfluid Star --- p.7 / Chapter 2.1 --- The Carter Formalism --- p.7 / Chapter 2.2 --- The Equilibrium Superfluid Star Models --- p.9 / Chapter 2.3 --- Non-Radial Oscillations of Superfluid Neutron Star --- p.13 / Chapter 2.3.1 --- Equations for Even-Parity Perturbations --- p.16 / Chapter 2.3.2 --- Equations for Odd-Parity Perturbations --- p.18 / Chapter 2.3.3 --- Linearised Equations Outside the Star --- p.19 / Chapter 2.3.4 --- Boundary Conditions for Quasinormal Modes --- p.21 / Chapter 2.3.5 --- Quasinormal Mode Spectrum of Superfluid Stars --- p.22 / Chapter 3 --- Universality in Superfluidf-mode --- p.25 / Chapter 3.1 --- What is an f-mode? --- p.25 / Chapter 3.2 --- Uncoupled Polytropic Master Function for Superfluid Stars --- p.27 / Chapter 3.3 --- Reparametrising the Uncoupled Polytropic Master Function --- p.29 / Chapter 3.4 --- f-mode Frequency of Uncoupled Polytropic Superfluid Stars --- p.30 / Chapter 3.5 --- "Derivation of Superfluid Mode Frequency for a Newtonian Sphere of Two Homogeneous, Incompressible, Uncoupled Fluids" --- p.40 / Chapter 4 --- Effects of Entrainment on Superfluid Mode Frequencies --- p.45 / Chapter 4.1 --- What is entrainment? --- p.45 / Chapter 4.2 --- Numerical Results --- p.48 / Chapter 4.3 --- Newtonian Variational Formalism --- p.51 / Chapter 4.4 --- Deriving the Approximate First Order Shift --- p.54 / Chapter 5 --- Variational Principle for Polar Modes --- p.60 / Chapter 5.1 --- Alternative Set of Perturbed Equations for Superfluid Neutron Star --- p.60 / Chapter 5.2 --- Boundary Conditions for Polar Quasinormal Modes --- p.64 / Chapter 5.3 --- Deriving the Variational Principle --- p.65 / Chapter 5.4 --- Recasting the Principle in Abstract Notation --- p.67 / Chapter 5.5 --- Doing Away with the Constraint Equations --- p.70 / Chapter 5.6 --- Regarding the Purely Real Nature of the First Order Term --- p.71 / Chapter 5.7 --- First Order Shift in Mode Frequency due to Entrainment --- p.74 / Chapter 6 --- Excitation of Quasinormal Modes --- p.77 / Chapter 6.1 --- Perturbed Equations Inside the Star --- p.77 / Chapter 6.2 --- Perturbed Equations Outside the Star --- p.78 / Chapter 6.3 --- Circular Orbits in Schwarzschild Spacetime --- p.80 / Chapter 6.4 --- Calculation of Source Term --- p.82 / Chapter 6.5 --- Determination of Amplitude --- p.85 / Chapter 6.6 --- Numerical Procedures --- p.86 / Chapter 6.7 --- Numerical Results --- p.89 / Chapter 7 --- Stability of Non-rotating Newtonian Superfluid Stars to Non-radial Oscillations --- p.91 / Chapter 7.1 --- Introduction --- p.91 / Chapter 7.2 --- Two-fluid Systems --- p.93 / Chapter 7.3 --- A Review of Basic Thermodynamics --- p.96 / Chapter 7.4 --- Perturbed System of Equations --- p.100 / Chapter 7.5 --- Schwarzschild Discriminant --- p.102 / Chapter 7.6 --- Variational Principle for Mode Frequency --- p.105 / Chapter 7.7 --- Stability of Polar Oscillations --- p.108 / Chapter 7.7.1 --- A Sufficient Condition for Stability --- p.109 / Chapter 7.7.2 --- A Necessary and Sufficient Condition for the Occurrence of Zero-frequency Modes --- p.112 / Chapter 7.7.3 --- Conditions for Instability --- p.119 / Chapter 7.8 --- A Little Application to Zero-temperature Superfluid Star --- p.121 / Chapter 7.9 --- Inclusion of Non-dissipative Magnus-typed Force --- p.122 / Chapter 7.10 --- Conclusion --- p.123 / Chapter 8 --- A Single Scalar Governing Stability of Newtonian Superfluid Neutron Stars to Non-radial Oscillations --- p.125 / Chapter 8.1 --- Introduction --- p.125 / Chapter 8.2 --- Summary of Results of the Last Chapter --- p.126 / Chapter 8.3 --- Motivation --- p.129 / Chapter 8.4 --- Occurrence of Neutral Modes --- p.131 / Chapter 8.5 --- S> 0 Implies Stability to Non-radial Oscillations --- p.133 / Chapter 8.6 --- S < 0 On a Finite Interval of r Implies Instability --- p.135 / Chapter 8.7 --- Conclusion --- p.137 / Chapter 9 --- Lagrangian Perturbation Theory for Rotating Non-relativistic Superfluid Stars --- p.138 / Chapter 9.1 --- Perturbation Operators --- p.139 / Chapter 9.2 --- Perturbing the Dynamical Equations --- p.143 / Chapter 9.3 --- Variational Principle and Symplectic Structure --- p.147 / Chapter 9.4 --- Showing Antisymmetry of B --- p.149 / Chapter 9.5 --- Showing Symmetry of C --- p.154 / Chapter 9.6 --- Canonical Displacement --- p.157 / Chapter 9.7 --- Using Canonical Energy in Stability Calculation --- p.163 / Chapter 9.8 --- Instability of r-mode for a Superfluid Star --- p.164 / Chapter 9.9 --- CFS Instability of Normal Modes --- p.169 / Chapter 10 --- Conclusion --- p.172 / Chapter A --- Some Useful Relations --- p.174 / Chapter B --- Derivation of Equations Given in Section 5.1 --- p.176 / Chapter C --- Order Analysis of Quantities at Stellar Radius --- p.179 / Chapter D --- Condition for the Occurrence of Non-radiating Modes --- p.182 / Chapter E --- Perturbed Equations for Polar Oscillations and Boundary Conditions --- p.186 / Chapter F --- Deriving the Variational Principle --- p.191 / Chapter G --- Discerning Similarity with Ordinary-fluid Variational Expression --- p.195 / Chapter G.l --- T'=0 --- p.195 / Chapter G.2 --- T'=0 --- p.199 / Chapter H --- A Condition for Instability of a Dynamical System --- p.202 / Chapter I --- Derivation of Zeroth-order r-mode Frequency --- p.205 / Chapter J --- Spin-s Spherical Harmonics --- p.207 / Chapter J.1 --- Spin-s Quantities --- p.207 / Chapter J.2 --- Motivation of Spin-s Spherical Harmonics --- p.208 / Chapter J.3 --- Proof of a Relation --- p.210 / Bibliography --- p.212

Chan, Pak On = 星體震動的分析方法 / 陳柏安. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (p. 117-119). / Abstracts in English and Chinese. / Chan, Pak On = Xing ti zhen dong de fen xi fang fa / Chen Boan. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Outline of the Content --- p.3 / Chapter 2 --- Preliminaries --- p.5 / Chapter 2.1 --- Einstein Equation --- p.5 / Chapter 2.1.1 --- Hydrostatic Equilibrium --- p.6 / Chapter 2.1.2 --- Linearized Stellar Pulsation --- p.7 / Chapter 2.1.3 --- Gravitational Radiation --- p.11 / Chapter 2.2 --- Classification of Modes --- p.13 / Chapter 2.2.1 --- Fundamental Mode --- p.14 / Chapter 2.2.2 --- Pressure Modes --- p.14 / Chapter 2.2.3 --- Gravity Modes --- p.14 / Chapter 2.3 --- Relativistic Cowling Approximation --- p.15 / Chapter 3 --- Stellar Structure of Quark Stars --- p.19 / Chapter 3.1 --- Ordinary Quark Stars --- p.19 / Chapter 3.1.1 --- Stellar Profile --- p.20 / Chapter 3.1.2 --- Radius and Mass --- p.27 / Chapter 3.1.3 --- Moment of Inertia --- p.30 / Chapter 3.2 --- Effects of Finite Strange Quark Mass and Finite Temperature --- p.32 / Chapter 3.2.1 --- Sommerfeld's Expansions --- p.33 / Chapter 3.2.2 --- Static EOS for Quark Matter --- p.35 / Chapter 3.2.3 --- Corrections to Ordinary Quark Stars --- p.37 / Chapter 3.2.4 --- Induced Buoyancy under Adiabaticity --- p.40 / Chapter 3.2.5 --- Induced Buoyancy under Fixed Composition --- p.45 / Chapter 3.3 --- Addition of Nuclear Crust --- p.47 / Chapter 4 --- Pressure Modes --- p.52 / Chapter 4.1 --- Sturm-Liouville Equation for p-modes --- p.52 / Chapter 4.2 --- Asymptotic Expansion --- p.54 / Chapter 4.3 --- "P""modes for Quark Stars" --- p.57 / Chapter 4.4 --- p-modes for Neutron Stars --- p.62 / Chapter 4.5 --- p-modes for Hybrid Stars --- p.65 / Chapter 5 --- Gravity Modes --- p.74 / Chapter 5.1 --- Sturm-Liouville Equation for modes --- p.74 / Chapter 5.2 --- Asymptotic Expansion --- p.76 / Chapter 5.3 --- g-modes for Quark Stars --- p.78 / Chapter 5.4 --- modes for Hybrid Stars --- p.83 / Chapter 5.5 --- Conditions on the modes --- p.88 / Chapter 6 --- Fundamental Mode --- p.93 / Chapter 6.1 --- Overview of the f-mode Universalities --- p.93 / Chapter 6.2 --- Relation between Real Part and Imaginary Part of Mwf --- p.95 / Chapter 6.3 --- New Universalities of f-mode --- p.96 / Chapter 7 --- Conclusions and Remarks --- p.104 / Chapter A --- Scattering Approximation --- p.106 / Chapter B --- Series Solution to Stellar Profile of Quark Stars --- p.108 / Chapter C --- AAKAS Formalism under Cowling Approximation --- p.113 / Chapter D --- Series Solutions to the Spectra of p-modes and g-modes --- p.114 / Bibliography --- p.117

No description available.

Optical imaging polarimetry has been performed on a small sample of objects which are associated with that stage of stellar evolution occurring between the Asymptotic Giant Branch and full Planetary Nebula. Three such systems are considered, specifically, the young planetary nebulae M 1-16 and Mz3, and the protoplanetary nebula, IRAS 09371+1212 (the 'Frosty Leo' nebula). The work is based upon CCD polarimetry obtained with the Durham Imaging Polarimeter. Planetary nebulae are believed to form as a low to intermediate mass star evolves from the main sequence, through the mass-loss stages of the Red Giant Branch and Asymptotic Giant Branch, towards its final destiny as a White Dwarf. A brief review of the relevant aspects of post-main sequence stellar evolution is given as a basis for understanding the transitionary planetary nebula phase in relation to the character of the central star and its role in the creation of a nebula. The theory of light scattering from both homogeneous and core-mantle spherical dust grains (Mie theory) is discussed. The results of a series of scattering calculations, using the theory, for dust grains composed of those materials believed to be abundant in the atmospheres of late-type stars and planetary nebulae are presented. The levels of polarization and scattered intensities predicted in the scattering analysis have been applied in the interpretation of the polarimetric data for the three planetary nebulae. Constraints upon the nature of the dust component, the size distribution of the dust and the nebula geometry are suggested for each of the nebulae. The inferred character of the dust material is in good agreement with the classification of the nebulae using the two-colour diagram for the IRAS fluxes.

Long-slit spectra for the photometric axes of a sample of 14 elliptical galaxies, predominantly low-luminosity ellipticals, in the Virgo cluster and in nearby groups, are studied to investigate the galaxy kinematical structure and stellar evolutionary history. To determine the galaxy kinematical structure, the shape of the line-of-sight velocity distribution (hereafter LOSVD) is measured using the Fourier Correlation Quotient method of Bender (1990), adopting the parametrisation of the LOSVD due to van der Marel and Franx (1993). This parametrisation enables the asymmetrical and symmetrical deviations of the LOSVD from a Gaussian function to be measured by the amplitudes H(_3) and H(_4) of the Gauss-Hermite series respectively. Rotation, velocity dispersion (σ), H(_3) and H(_4) are determined as a function of radius for both the major and minor axes of our sample. To summarise, LOSVD asymmetries were measured for the major axes of 12 galaxies which in the majority of cases have been interpreted as evidence for central disk-like components; evidence of both radial and tangential anisotropy were found from the measurement of H(_4); central decreases in σ are measured for 3 galaxies, which is interpreted as evidence that they have undergone some form of merger or interaction. On the basis of their measurements, galaxies are classified into 3 classes: types 1, 2 and 3. "Type 1" galaxies show strong evidence for both disk and bulge components and have the greatest measured values of H(_3) for our sample. Galaxies of "type 2" show strong evidence for embedded disk components and most (3 of 4) are measured to have central decreases in a. "Type 3" galaxies have kinematically-decoupled cores. Other galaxies, not classified, are NGC 3379 and NGC 4468.Measurements of the line-strength indices Mg(_b), Mg(_2), Hβ, Fe5270, Fe5335 and <Fe> are determined as a function of radius for all spectra and established to the Lick/IDS scale. The relations Mg’(_b)-Mg(_2), Mg’(_b), - log(σ), Mg(_b)- <Fe> and Hβ-[Mg(_b) <Fe>] are then studied. The Mg’(_b),-Mg(_2) relation of Wegner et al. (1998) and the calibrations of Worthey (1994) are compared with measurements here: this is used as a check of our calibration of Mg’(b), and Mg(_2). Measurements in the Mg’(_b)-log(σ) plane are considered separately for each galaxy and compared with the central relation of Colless et al. (1998). Measurements for most galaxies are found to be in good agreement with this relation. Measurements of Mg(_b) and <Fe> are similarly considered for each galaxy and compared with the predictions of the models of Worthey (1994). For the majority of galaxies, measurements are clearly offset from the Mg(_b)-<Fe> model grid of Worthey (1994), representing an [(^Mg)-(_Fe)] overabundance. This is an important result which shows that the [(^Mg)-(_Fe)] overabundance detected previously for the giant ellipticals similarly exists for ellipticals of the low luminosities studied here. For most galaxies this overabundance is found to be a constant function of radius. For the "type 2" galaxy NGC 3605, and NGC 4468, measurements are consistent with solar abundance ratios. Finally, measurements of Hβ and [Mg(_b) <Fe>] are compared with the models of Worthey (1994) to distinguish gradients in both age and metallicity. For all galaxies, gradients in metallicity are found with metallicity decreasing as a function of radius. For 5 galaxies (NGC 4564, NGC 3377, NGC 4478, NGC 4339 and NGC 3605) age gradients are also detected, with the galaxy centre shown to be younger than the surrounding galaxy. Interpreting these results together, different formation scenarios are proposed for the different galaxy types. For galaxies of "type 1", formation by homogenous, dissipational collapse is proposed. Galaxies of "type 2" show evidence for a less homogenous evolutionary history involving dissipationless collapse. No conclusive scenario is proposed for galaxies of "type 3".