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Title of Thesis
STUDY OF HIGH β RELAXED STATE OF PLASMA |
Author(s)
MUHAMMAD IQBAL |
Institute/University/Department Details
Department of Physics/ Quaid-i-Azam University, Islamabad |
Session
2001 |
Subject
Physics |
Number of Pages
97 |
Keywords (Extracted from title, table of contents and abstract of thesis)
high β relaxed state, plasma, beltrami fields, mhd plasma, eruptive events, solar corona, helicities |
Abstract Beltrami fields, eigen functions of the curl operator, represent the static force-free relaxed state of a single-fluid MHD plasma and correspond to the alignment of magnetic field and current density. The double Beltrami fields which are the superposition of two different Beltrami fields, express a more general relaxed state of a two-fluid MHD plasma. The new relaxed states, despite its simple mathematical structure, encompass a wide class of steady states in mathematical Physics and explain interesting phenomena. Plasma configurations are investigated employing the double Beltrami fields. Our numerical results reveal that relaxed states of plasma exhibiting ultrahigh β associated with minimum values of field-aligned current and flow can be created which are suitable for the advanced fusion concept. Furthermore, a set of algebraic equations is derived which relates the parameters of double Beltrami field (amplitudes and eigenvalues) and the ideal invariants (energy and helicities) of the system. These equations can be used to study the existence of solutions and catastrophic change of structures in relaxed equilibria in different plasma configurations. For a given set of energy and helicities, the catastrophic loss of equilibrium is observed when flux loops are compressed by varying the control parameter. This study could be very helpful to understand the eruptive events in solar corona.
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Chapter |
Title of the Chapters |
Page |
Size (KB) |
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| 1 |
0 |
Contents |
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 119.95 KB |
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| 2 |
1 |
Introduction |
3 |
 95.99 KB |
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1.1 |
Motivation |
3 |
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1.2 |
Layout of thesis |
9 |
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| 3 |
2 |
Beltrami Fields |
10 |
 183.67 KB |
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2.1 |
Self-organization in MHD System . |
10 |
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2.2 |
Woltjer's Theorem |
14 |
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2.3 |
Beltrami Fields |
19 |
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2.4 |
Solar Coronal Loops |
22 |
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| 4 |
3 |
Double Beltrami Fields |
25 |
 232.24 KB |
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3.1 |
Steinhauer -Ishida Model |
26 |
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3.2 |
Local and Global Invariance of Helicities |
30 |
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3.3 |
Relaxed State |
32 |
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3.4 |
Mahajan - Yoshida Model |
34 |
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3.5 |
Invariance of Helicities of Double Curl Beltrami System |
40 |
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3.6 |
Vaxiational Principle for Double Curl Beltrami System |
43 |
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3.7 |
Double Curl Beltrami and Self-helicities |
45 |
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| 5 |
4 |
Analytical Solutions in Cylindrical Geometry |
47 |
 288.33 KB |
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4.1 |
Cylindrical Plasma System |
48 |
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4.2 |
Radial Profiles |
52 |
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4.3 |
Internal Conductor Plasma System |
59 |
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| 6 |
5 |
Catastrophic Change of Relaxed Equilibria |
73 |
 123.85 KB |
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5.1 |
Double Beltrami Fields |
74 |
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5.2 |
Conservation Laws for Double Beltrami Fields |
76 |
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5.3 |
Analysis of Relaxed Equilibria |
83 |
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5.4 |
Application to Solar Corona |
86 |
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| 7 |
6 |
Summary and Conclusions |
88 |
 52.04 KB |
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