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Polarized Radiation from Inhomogeneous Shocks. Kinwah Wu Louisiana State University and Agricultural & Mechanical College

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Polarized Radiation from Inhomogeneous Shocks. Kinwah Wu Louisiana State University and Agricultural & Mechanical College Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1989 Polarized Radiation From Inhomogeneous Shocks. Kinwah Wu Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Wu, Kinwah, "Polarized Radiation From Inhomogeneous Shocks." (1989). LSU Historical Dissertations and Theses. 4825. https://digitalcommons.lsu.edu/gradschool_disstheses/4825 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS The most advanced technology has been used to photo­ graph and reproduce this manuscript from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. 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 bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI 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. 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University Microfilms International A Bell & Howell Information Company 3 0 0 North Z eeb Road, Ann Arbor, Ml 48106-1346 USA 313/761-4700 800/521-0600 Order Number 9017309 Polarized radiation from inhomogeneous shocks Wu, Kinwah, Ph.D. The Louisiana State University and Agricultural and Mechanical Col., 1989 UMI 300 N. Zeeb Rd. Ann Arbor, MI 48106 POLARIZED RADIATION FROM INHOMOGENEOUS SHOCKS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Physics and Astronomy by Ivinwah Wu B.Sc.(Hon.) The Chinese University of Hong Kong, 1983 M.S. Louisiana State University, 1984 August 1989 ’’The heavens declare the glory of God; the skies proclaim the work of His hands. Day after day they pour fourth speech; night after night they display knowledge.” Psalms 19:1,2 ii ACKNOWLEDGEMENTS I would like to express my appreciation and thanks to my advisor, Dr. G. Chan- mugam, for his guidance and encouragement during the course of this research. His positive criticisms and friendship made my graduate studies a memorable experi­ ence. I would like to thank Dr. J. E. Tohline for many stimulating discussions and for acting as my advisor when Dr. Chanmugam was on leave. I also enjoyed valuable discussions with Dr. D. T. Wickramasinghe (Australian National University) who always challenged my works at conferences and Mr. Y. M. Sang who shared with me his interest in pulsars. I thank Dr. P. E. Barrett (South African Observatory) for correspondence on cyclotron opacities. Thanks also to Dr. D. Koester who broadened my knowledge about white dwarfs, Dr. A. R. P. Rau who patiently explained to me about hydrogen atoms in strong magnetic fields, and Dr. R. M. Light who shared the excitement about his work with me. I thank Miss M. Lee for assistance in operating the computer and Dr. A. Landolt for generously letting me use his computer and library. I would like to thank Dr. D. S. Shih, Dr. L. H. Chan, Pastor J. Mitchel, Mr. M. W. Courtney, Mr. C. W. Fong, Mr. K, T. Wong, Dr. H. Tsuei and the Morrison family for a lot of encouragement. I am particularly thankful to Mr. K. C. Kwong for his friendship, discussions and prayers. Without these people, this work could hardly have been finished. I sincerely wish all of them the best, and may God bless them. i i i Finally, I acknowledge the support from the Department of Physics and As­ tronomy, especially the faculty of the astronomy group, and the National Science Foundation. This work was supported by NSF grants AST-8219598 and 8700742. To my parents v Table of Contents List of Figures ............................................................................................. mi L ist o f T a b le s ................................................................................................ .x A b stra c t ......................................................................................................... xi I n tr o d u c tio n .................................................................................................. ..1 Radiation from AM Her Binaries ....................................................... , 12 2.1. Emission Lines ................................................................................. 12 2.2. X-rays ........................................................................................................ 14 2.3. Polarized Optical/IR Radiation ............................................................ 17 2.4. Cyclotron L ines ....................................................................................... 22 Radiation from Magnetized Plasmas ................................................. 23 3.1. Radiative T ransfer........................................................................ ......... 23 3.2. Cyclotron Absorption Coefficients ........................................................ 26 Polarized Radiation from Accretion Columns ............................... 32 4.1. Homogeneous Cyclotron Emission Regions ........................................ 32 4.2. Early Inhomogeneous Calculations ...................................................... 34 Hydrodynamic Structures ....................................................................... 40 5.1. Hydrodynamic Flows .............................................................................. 41 5.2. Three-dimensional Structure of Bremsstrahlung-dominated Shocks 46 Polarized Radiation from 3D Accretion Shocks ........................... 62 6.1. Symmetric Accretion Rate ................................................................... 62 6.2. Implications of the Inhomogeneous Shocks ........................................ 69 6.3. Asymmetric Accretion R a te ................................................................. 71 Future Work ................................................................................................. 75 vi 7.1. Light C urves ......................................................................................................75 7.2. Cyclotron Harmonics .......................................................................................75 7.3. Quasi-Periodic-Oscillations ............................................................................. 76 8. Conclusions ....................................................................................................79 References......................................................................................................82 Appendices: Letter from the Managing Editor of The Astrophysical Journal ......................90 A. ’’Cyclotron Spectra from Inhomogeneous Accretion Columns” by K. Wu and G. Chanmugam, 1988, Ap. J., 331, 861 ..................................... 91 B. ’’Cyclotron Spectra from Inhomogeneous Accretion Columns II: Polarization” by K. Wu and G. Chanmugam, 1989, Ap. J., in press. .. .107 V ita................................................................................................................ 147 Approval Sheet ........................................................................................... 149 vii List of Figures X. (a) Cataclysmic Variable ..........................................................................................2 (b) DQ Herculis Binary .............................................................................................4 (c) AM Herculis Binary ............................................ 7 2. Photometric and Polarization Light Curves of ST LMi ........................ 19 3. Optical Spectra and Circular Polarization of ST LM i .............. 21 4. (a) T - N Diagram Delineating Bremsstrahlung and Cyclotron Dominated Domains for Plasma with Size I = 106c m ...................................................... 42 (b) Same as (a) for I = 107cm ................................... 43 (c) Same as (a) for I = 108c m .......................................... 44 5. Local Shock Heights for Different Local Accretion Rates .......................... 47 6 . Shock Surface for a Uniform Accretion Rate ........................................ 49 7. Same as
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