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Twisted Magnetic Fluxtubes in the Sun (Record no. 19512)

MARC details
000 -LEADER
fixed length control field 03552nam a2200253Ia 4500
003 - CONTROL NUMBER IDENTIFIER
control field IN-BaIIA
005 - DATE AND TIME OF LATEST TRANSACTION
control field 20211110160116.0
008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION
fixed length control field 211028s9999 xx 000 0 eng d
040 ## - CATALOGING SOURCE
Transcribing agency IIA Library
100 ## - MAIN ENTRY--PERSONAL NAME
Personal name Sen, Samrat
9 (RLIN) 37310
Relator term Author
245 #0 - TITLE STATEMENT
Title Twisted Magnetic Fluxtubes in the Sun
Remainder of title a thesis submitted for the degree of philosophy in the department of physics, Pondicherry University, Puduecheery
Statement of responsibility, etc. Samrat Sen
Medium [Ph.D Thesis]
260 ## - PUBLICATION, DISTRIBUTION, ETC.
Place of publication, distribution, etc. Bangalore
Name of publisher, distributor, etc. Indian Institute of Astrophysics
Date of publication, distribution, etc. 2020
300 ## - PHYSICAL DESCRIPTION
Extent xx, 208p.
500 ## - GENERAL NOTE
General note Ph.D. Thesis, Pondicherry University, Puducherry
502 ## - DISSERTATION NOTE
Degree type Doctor of Philosophy
Name of granting institution Pondicherry University, Puducherry
Year degree granted 2020
520 ## - SUMMARY, ETC.
Summary, etc. The study of magnetic fluxtubes is a very important aspect as it plays an important<br/>role in several astrophysical phenomena in the solar atmosphere. Thus, it is very<br/>important to understand the properties and structures of the magnetic configuration<br/>and thermodynamic quantities of the fluxtubes. In this Thesis, we construct two<br/><br/>different classes of fluxtube models with twisted magnetic fields by solving the Grad-<br/>Shafranov equation (GSE) semi-analytically. We also calculate the energy distribution<br/><br/>of a braided system of magnetic field lines using the Self-Organized Criticality (SOC)<br/>model.<br/><br/>The fluxtube models we build are in magnetohydrostatic (MHS) equilibria for an ax-<br/>isymmetric geometry, spanning from the photosphere to the lower part of the transition<br/><br/>region within a realistic stratified solar atmosphere subject to solar gravity. We as-<br/>sume a general quadratic expression of the magnetic flux function for the gas pressure<br/><br/>and poloidal current and solve the GSE analytically. One solution is a combination<br/>of a homogeneous and a particular part where the former is separable by a Coulomb<br/><br/>function in r and exponential in z, while the particular part is an open configura-<br/>tion that has no z dependence. The other fluxtube model can be branched out into<br/><br/>open and closed field solutions by using a self-similar formulation with different profile<br/>functions and incorporating stratified solar gravity to maintain the magnetohydrostatic<br/>equilibria, which is a modification of earlier self-similar models by a twist. We study<br/><br/>the admitted parameter space that is consistent with the conditions in the solar at-<br/>mosphere and derive magnetic and the thermodynamic structures inside the fluxtubes<br/><br/>that are reasonably consistent with the photospheric magnetic bright points (MBPs)<br/>for both open and closed field Coulomb function and self-similar models as estimated<br/>from observations and simulations. The obtained open fluxtube solutions can be used<br/>as the background conditions for the numerical simulations for the study of the wave propagation through the fluxtubes. The closed field solutions can be used to construct<br/>realistic magnetic canopies in the solar atmosphere.<br/><br/>We estimate winding number distributions of braided topologies. We also calculate the<br/>power-law index of the energy distribution for the solar radio flare events on 14 February<br/>2011, and 11 March 2011, captured by Gauribidanur Radio Telescope, and compare<br/>the theoretical prediction of the power-law index with the observational estimate.
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical term or geographic name entry element Fluxtube models
9 (RLIN) 37311
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical term or geographic name entry element Magnetic fields
9 (RLIN) 530
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical term or geographic name entry element Solor Atmosphere
9 (RLIN) 37312
650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM
Topical term or geographic name entry element Sun
9 (RLIN) 1200
700 ## - ADDED ENTRY--PERSONAL NAME
Personal name Arun Mangalam
Relator term Supervisor
9 (RLIN) 37029
856 ## - ELECTRONIC LOCATION AND ACCESS
Uniform Resource Identifier <a href="http://prints.iiap.res.in/handle/2248/7523">http://prints.iiap.res.in/handle/2248/7523</a>
Link text Click Here to Access eThesis
942 ## - ADDED ENTRY ELEMENTS (KOHA)
Koha item type Thesis & Dissertations
Source of classification or shelving scheme Universal Decimal Classification
Holdings
Withdrawn status Lost status Source of classification or shelving scheme Damaged status Not for loan Home library Current library Shelving location Date acquired Barcode Date last seen Price effective from Koha item type
    Universal Decimal Classification     IIA Library-Bangalore IIA Library-Bangalore General Stacks 04/11/2020 20434 05/11/2021 04/11/2020 Thesis & Dissertations

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