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Ring Current -Atmosphere Interactions Model with Stormtime Magnetic Field University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Fall 2007 Ring current -atmosphere interactions model with stormtime magnetic field Alexander Emilov Vapirev University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation Vapirev, Alexander Emilov, "Ring current -atmosphere interactions model with stormtime magnetic field" (2007). Doctoral Dissertations. 406. https://scholars.unh.edu/dissertation/406 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. R i n g C u r r e n t - A t m o s p h e r e I nteractions M o d e l W i t h S t o r m t i m e M a g n e t i c F i e l d b y ALEXANDER EMILOV VAPIREV M.S., Sofia University, Sofia, Bulgaria, 1999 DISSERTATION Submitted to the University of New Hampshire in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Physics September 2007 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 3277150 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. ® UMI UMI Microform 3277150 Copyright 2007 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. This dissertation has been examined and approved. \ J . ) . Dissertation Director, Vania K. Jordanova, Adjunct Re­ search Associate Professor of Physics Professo of PhysicsRoy Torbe: Professo of PhysicsRoy Joachim Reeder, Associate Professor of Physics Lynn Kistler, Associate Professor of Physics Jochen Heisenberg, Professor of Physics Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. D e d ic a t io n To my parents ”An expert is a man who has made all the mistakes which can be made in a very narrow field. ” - Niels Bohr iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. A cknowledgments I thank my academic adviser Prof. Vania Jordanova for giving me the opportunity to work with her. I thank her for her guidance throughout my research and studies. It has been a privilege to work with her. I thank the members of my dissertation committee for their time and patience and their useful suggestions and helpful comments. I want to thank all my teachers and colleagues from the Bulgarian Academy of Sciences and the University of Sofia and especially those at the department of Nuclear Energy and Nuclear Technologies and the department of Quantum Electronics and Laser Technologies. I want to thank the academic program coordinators Katie Makem and Kathy Giberson for their help on so many occasions. I want to thank all my colleagues at UNH and especially Douglas Larson, Burgin Donmez and Georgi Nenchev for all the help and conversations. I also want to thank Sorin Zaharia (LANL) and Yoshizumi Miyoshi (Nagoya University) for the useful discussions and support on numerous occasions. I want to express my sincere gratitude to Nikolay Tsyganenko (GSFC) and Reiner Friedel (LANL) for their help. I thank my parents, my brother, my sister and all my friends for their love and support through all these years. iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. C o n t e n t s D e d ic a t io n .............................................. iii A cknowledgments ..................................................................................................................................... iv L is t o f T a b l e s ............................................................................................................................................. v iii L is t o f F ig u r e s ......................................................................................................................................... ix A b s t r a c t ......................................................................................................................................................... x v ii 1 I ntroduction 1 2 O r ig in a n d D e v e l o p m e n t o f th e T e r r e s t r ia l R in g C u r r e n t 9 2.1 General Structure of the Ring C urrent ................................................................... 9 2.2 Measurements .............................................................................................................. 12 2.3 Sources of Ring Current Pa rtic le s ........................................................................... 16 2.3.1 The Solar W ind ........................................................................................... 18 2.3.2 The Ionosphere .............................................................................................. 19 2.3.3 Compositional C h a n g e s .............................................................................. 21 2.4 Ionospheric o u tflo w .................................................................................................... 23 2.5 Charge Exchange Losses........................................................................................... 26 2.5.1 Charge Exchange Processes....................................................................... 26 2.5.2 Energetic Neutral Atoms .......................................................................... 28 2.6 Coulomb C o llisio n s .................................................................................................... 29 2.7 Wave — Particle Interactions ................................................................................ 31 v Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 3 T heoretical A pproach 44 3.1 Kinetic E q u a tio n ............................................................................................................. 44 3.2 Drifts of Ring Current Particles.................................................................................. 46 3.2.1 Radial and Azimuthal Drifts ........................................................................ 47 3.2.2 /ro — Drift............................................................................................................. 49 3.2.3 Energy Drift ....................................................................................................... 50 3.3 Charge Exchange Losses ................................................................................................ 50 3.4 Atmospheric Losses.......................................................................................................... 52 3.5 Ring Current Characteristics and Aeronomical E ffects ...................................... 53 3.6 Tsyganenko Magnetospheric Field Model .............................................................. 54 4 T he N umerical M odel 58 4.1 The Numerical Scheme of RAM .................................................................................. 58 4.1.1 Time splitting ................................................................................................... 58 4.1.2 High — Resolution Schemes............................................................................ 59 4.2 Bounce — Averaging along a Field L in e ................................................................. 60 4.3 Numerical Accuracy Tests of the Bounce — Averaging Technique .................. 62 4.4 Accuracy Tests for R A M ................................................................................................ 63 4.4.1 Equatorial Particle F lu x ..................... 64 4.4.2 Total Energy and Total Number of Particles.............................................. 65 5 M odel R esults 77 5.1 Observations .................................................................................................................... 77 5.1.1 Interplanetary D a ta ......................................................................................... 77 5.1.2 Magnetospheric Data ...................................................................................... 78 5.1.3 Input data for T04s m od el ............................................................................... 79 vi Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 5.2 Bounce — Averaged Exospheric Hydrogen Density and Magnetic Gradient — Curvature Drift Velocity ........................................................................................... 79 5.3 Time Evolution of the Trapped Equatorial Flu x .................................................
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