Spelling suggestions: "subject:"compact objects (astronomy)"" "subject:"compact objects (gastronomy)""
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Compact stars in Eddington-inspired Born-Infeld gravity and general relativity / 愛丁頓-玻恩-英費爾德重力理論和廣義相對論下的致密星 / CUHK electronic theses & dissertations collection / Compact stars in Eddington-inspired Born-Infeld gravity and general relativity / Aidingdun-Boen-Yingfeierde zhong li li lun he guang yi xiang dui lun xia de zhi mi xingJanuary 2015 (has links)
Sham, Yu Hin = 愛丁頓-玻恩-英費爾德重力理論和廣義相對論下的致密星 / 岑宇軒. / Thesis Ph.D. Chinese University of Hong Kong 2015. / Includes bibliographical references (leaves 137-143). / Abstracts also in Chinese. / Title from PDF title page (viewed on 15, September, 2016). / Sham, Yu Hin = Aidingdun-Boen-Yingfeierde zhong li li lun he guang yi xiang dui lun xia de zhi mi xing / Cen Yuxuan.
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Topics in compact stars. / 致密星的研究 / Topics in compact stars. / Zhi mi xing de yan jiuJanuary 2007 (has links)
Tso Ka Yee = 致密星的研究 / 曹家怡. / Thesis submitted in: September 2006. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 86-88). / Abstracts in English and Chinese. / Tso Ka Yee = Zhi mi xing de yan jiu / Cao Jiayi. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Brief History of Neutron Stars --- p.1 / Chapter 1.2 --- The Proposal of Strange Quark Stars --- p.3 / Chapter 1.3 --- "Observation of Stellar Masses, Radii and Moment of Inertia" --- p.4 / Chapter 1.3.1 --- Radius Measurement --- p.5 / Chapter 1.3.2 --- Mass Measurement --- p.6 / Chapter 1.3.3 --- Moment of Inertia Measurement --- p.8 / Chapter 1.4 --- PSR B1828-11 --- p.8 / Chapter 1.5 --- Effect of rotation on a star's precession --- p.12 / Chapter 1.5.1 --- Reference Frames of the Star --- p.12 / Chapter 1.5.2 --- Dynamics of Free Precession --- p.14 / Chapter 1.6 --- Motivation --- p.17 / Chapter 2 --- Static structure of a compact star --- p.18 / Chapter 2.1 --- Equation of State that We Used --- p.18 / Chapter 2.1.1 --- Thomas-Fermi Model (TF96) --- p.18 / Chapter 2.1.2 --- MIT Bag Model --- p.19 / Chapter 2.1.3 --- Perturbative QCD Model --- p.21 / Chapter 2.2 --- Non-relativistic compact stars --- p.23 / Chapter 2.2.1 --- Lane-Emden Equation --- p.23 / Chapter 2.3 --- General Relativistic Approach --- p.24 / Chapter 2.3.1 --- The Oppenheimer-Volkoff Equations --- p.24 / Chapter 2.3.2 --- Properties of Compact Stars --- p.26 / Chapter 3 --- Non-relativistic rotating star --- p.29 / Chapter 3.1 --- Rotating Lane-Emden Equations --- p.29 / Chapter 3.2 --- The Moment of Inertia Tensor --- p.34 / Chapter 3.3 --- Models --- p.35 / Chapter 3.4 --- Results --- p.38 / Chapter 3.5 --- Summary --- p.46 / Chapter 4 --- Relativistic rotating star --- p.47 / Chapter 4.1 --- Rotating metric --- p.48 / Chapter 4.2 --- Frame Dragging Effect --- p.49 / Chapter 4.3 --- Hartle-Thorne Perturbative Solution --- p.52 / Chapter 4.4 --- Results --- p.56 / Chapter 4.5 --- Summary --- p.65 / Chapter 5 --- Effects of extra dimensions on non-rotating stars --- p.66 / Chapter 5.1 --- Background of Extra dimensional theories --- p.66 / Chapter 5.2 --- Results --- p.69 / Chapter 5.3 --- Summary --- p.82 / Chapter 6 --- Conclusion --- p.84 / Bibliography --- p.86
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alytic approach to pulsations of compact stars. / 星體震動的分析方法 / An alytic approach to pulsations of compact stars. / Xing ti zhen dong de fen xi fang faJanuary 2011 (has links)
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
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Transients from the Birth and Death of Compact ObjectsMargalit, Ben January 2018 (has links)
Astrophysical compact objects --- white dwarfs (WDs), neutron stars (NSs), and stellar mass black holes (BHs) --- mark the endpoints of normal stellar evolution. Their birth is often associated with dramatic explosions known as core-collapse supernovae (SNe). Such SNe are archetypal ``transients'' --- astronomical events which produce detectable emission for only a limited period of time (measurable over human timescales). This dissertation investigates the astrophysical implications of the formation and destruction of compact objects with particular focus on the transient phenomena that may be produced in such events.
Part I is devoted to the ``death'' of compact objects by their coalescence with a binary companion. Such compact object binaries are driven towards merger by the extraction of orbital energy in the form of gravitational-waves (GW), and are thus prime targets for current and future GW detectors. In the first two chapters of Part I we consider the merger of a WD with a NS companion, beginning with Chapter 2, in which we explore the nuclearly-reactive accretion flow produced in the aftermath of such mergers and the possible `SN-like' transient it may give rise to. We continue in Chapter 3 by proposing that the late-time evolution of this post-merger accretion disk may result in terrestrial planet formation, broadly consistent with the mysterious ``pulsar planets'' observed orbiting PSR B1257+12. We shift our attention in the next couple chapters of this first part of the dissertation to binary NS mergers. In Chapter 4 we address the question of disk formation in the aftermath of the collapse of a rigidly-rotating supramassive NS, which is directly applicable to various models of gamma-ray bursts (GRBs). In Chapter 5 we utilize both GW and electromagnetic signatures of the first observed NS merger GW170817 to place new constraints on the NS equation of state.
Finally, in Part II of this dissertation, we explore the connection between transient phenomena ranging from long- and ultra-long- GRBs, to energetic super-luminous SNe (SLSNe) and fast radio bursts (FRB), and relate these to the ``birth'' of a rapidly rotating highly-magnetized NS, a millisecond ``magnetar''. In Chapter 6 we show that both jetted and thermal transients (namely a GRB and a SLSN) can be powered simultaneously by such magnetars, and explore the various observational implications of this connection. We end with Chapter 7 in which we study the photo-ionization of the medium surrounding a newly born magnetar, discussing the observational signatures related to the escape of this ionizing radiation. We additionally address the propagation of radio waves and the dispersion measure induced by such photo-ionization and apply these to show that FRBs are broadly consistent with having young magnetars as their progenitors.
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Gravitational waves and dynamical processes in hot newborn compact stars.January 2010 (has links)
Lau, Hoi Kwan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 208-212). / Abstracts in English and Chinese. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Gravitational wave astronomy --- p.1 / Chapter 1.2 --- Stellar pulsation and gravitational radiation --- p.3 / Chapter 1.3 --- Outline --- p.5 / Chapter 2 --- Hydrostatic stellar structure --- p.8 / Chapter 2.1 --- Structural equation --- p.9 / Chapter 3 --- Finite temperature equations of state of nuclear matter --- p.13 / Chapter 3.1 --- Finite temperature ordinary nuclear matter --- p.13 / Chapter 3.2 --- Strange Quark Matter --- p.15 / Chapter 3.3 --- Equilibrium and Dynamic EOS --- p.16 / Chapter 4 --- Stellar pulsation and gravitational radiation --- p.19 / Chapter 4.1 --- Linearized theory of general relativity --- p.19 / Chapter 4.2 --- Stellar oscillation --- p.25 / Chapter 4.3 --- Quasi-normal Mode --- p.28 / Chapter 4.3.1 --- f mode --- p.29 / Chapter 4.3.2 --- p mode --- p.29 / Chapter 4.3.3 --- g mode --- p.30 / Chapter 4.3.4 --- w mode --- p.31 / Chapter 5 --- Gravitational wave spectrum of hot compact stars --- p.32 / Chapter 5.1 --- Numerical results --- p.32 / Chapter 5.1.1 --- Temperature effect on QNM --- p.32 / Chapter 5.1.2 --- Temperature effect and QS model --- p.38 / Chapter 5.1.3 --- QNM shift due to phase transition --- p.41 / Chapter 5.2 --- Summary and prospective --- p.48 / Chapter 6 --- Universality of fundamental mode and spacetime mode --- p.50 / Chapter 6.1 --- Review --- p.50 / Chapter 6.2 --- Generic proposal of universalities --- p.53 / Chapter 6.2.1 --- Moment of Inertia --- p.54 / Chapter 6.2.2 --- Gravitational wave spectrum --- p.57 / Chapter 6.3 --- Universality on moment of inertia --- p.63 / Chapter 6.4 --- Origin of universality --- p.70 / Chapter 6.4.1 --- Tolman VII model --- p.71 / Chapter 6.4.2 --- Polytropic Model --- p.76 / Chapter 6.5 --- Application of universality --- p.82 / Chapter 6.6 --- Summary --- p.89 / Chapter 7 --- Quark star properties and gravity mode oscillation --- p.92 / Chapter 7.1 --- Introduction --- p.92 / Chapter 7.2 --- g mode frequencies of quark stars --- p.94 / Chapter 7.2.1 --- Temperature profile and p mode frequency --- p.96 / Chapter 7.2.2 --- Strange quark mass and Yp mode frequency --- p.104 / Chapter 7.3 --- Summary --- p.108 / Chapter 8 --- Gravitational radiation excitation by infalling shell --- p.111 / Chapter 8.1 --- Introduction --- p.111 / Chapter 8.2 --- Formalism --- p.116 / Chapter 8.2.1 --- Connection between star and vacuum --- p.117 / Chapter 8.2.2 --- Matter source --- p.121 / Chapter 8.2.3 --- Geodesic --- p.124 / Chapter 8.2.4 --- Source of infalling dust shell --- p.126 / Chapter 8.2.5 --- Green's function --- p.127 / Chapter 8.3 --- Gravitational Wave excitation by collapsing shell --- p.130 / Chapter 8.4 --- Features of radiation --- p.138 / Chapter 8.4.1 --- Power spectrum --- p.138 / Chapter 8.4.2 --- Wave function --- p.144 / Chapter 8.4.3 --- Energy of excitation --- p.147 / Chapter 8.5 --- Non-adiabatic oscillation --- p.153 / Chapter 8.5.1 --- Mathematical Background --- p.154 / Chapter 8.5.2 --- Numerical results --- p.158 / Chapter 8.6 --- General relativistic simulation --- p.163 / Chapter 8.6.1 --- Technical briefing --- p.163 / Chapter 8.6.2 --- Numerical results --- p.166 / Chapter 8.7 --- Summary --- p.174 / Chapter 9 --- Conclusion and remarks --- p.178 / Chapter A --- Unit conversions --- p.183 / Chapter B --- Series expansion of quark star EOS --- p.185 / Chapter C --- Accuracy of simplified mode extraction scheme --- p.188 / Chapter D --- Computation of moment of inertia --- p.193 / Chapter E --- Comment of exactness of inference scheme --- p.195 / Chapter E.1 --- Precision of the mass inferred --- p.195 / Chapter E.2 --- Accuracy of universality combinations --- p.199 / Chapter F --- Calculation of sound speed --- p.202 / Chapter G --- Mode extraction of non-adiabatic oscillation --- p.204 / Bibliography --- p.208
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Source modelling of extreme and intermediate mass ratio inspiralsHuerta Escudero, Eliu Antonio January 2011 (has links)
No description available.
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A study on non-radial fluid oscillation modes in compact stars / 有關在緻密星中流體振盪的研究 / CUHK electronic theses & dissertations collection / study on non-radial fluid oscillation modes in compact stars / You guan zai zhi mi xing zhong liu ti zhen dang de yan jiuJanuary 2013 (has links)
The objective of this thesis is to study the fluid oscillation modes in compact stars, understand their properties and infer stellar structures from their frequencies. The first part of the thesis focuses on the Newtonian theory of stellar pulsation and the Cowling approximation (CA), which neglects the change in gravitational potential. We modify the conventional CA, devise a more accurate version of the CA and calculate the first-order correction to the conventional CA. In the second part, we apply the variational approximation method proposed by Chandrasekhar [Astrophys. J. 139,664 (1963)] and δ-perturbation expansion proposed by Bender et. al. [J. Maths. Phys. 30, 1447 (1989)] to explain the universality in the relationships between the fundamental mode frequency and the moment of inertia of neutron stars, which was discovered by Lau et. al. [Astrophys. J. 714, 1234 (2010)]. We reveal that stiff equations of state are the conditions for the observed universality. In the third part, we consider the relativistic pulsation formulation and relativistic CAs for compact stars. We unify several known CAs with a single second-order differential equation. We also extend the modified CA derived from the formalism established by Allen et. al. [Phys. Rev. D 58, 124012 (1998)] to include the effect of buoyancy. Finally, we find the first-order and the second-order post-Newtonian expansions for the nonradial pulsations in quark stars. We derive an analytic formula expressing the fundamental mode frequency in terms of the compactness of quark stars. As a result, we are able to verify the universality mentioned above for quark stars. / 這論文是對在牛頓力學以及相對論框架下緻密星流體振盪的研究結果。論文第一部分集中討論牛頓力學下流體振盪以及近似方法。這近似方法忽略重力勢的擾動,令系統由四階微分方程減少為二階微分方程。我們修正了已往的近似方法和提出一個更精準的近似方法。第二部分包括變分近似方法。我們利用該方法和δ微擾理論解釋基本模式頻率的普通性。第三部分包括相對論框架下緻密星流體振盪和近似方法。我們以一條二階微分方程總結之前出現的近似方法並且在近似方法中加入浮力。最後,我們執行一階和二階的後牛頓展開,以分析夸克星的基本模式。我們驗證了展開的準確度和發現了基本模式頻率的方程。 / Chan, Tsang Keung = 有關在緻密星中流體振盪的研究 / 陳增強. / Thesis M.Phil. Chinese University of Hong Kong 2013. / Abstracts also in Chinese. / Title from PDF title page (viewed on 07, October, 2016). / Chan, Tsang Keung = You guan zai zhi mi xing zhong liu ti zhen dang de yan jiu / Chen Zengqiang. / Detailed summary in vernacular field only.
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