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Information to Users INFORMATION TO USERS This manuscript has been reproduced 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. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. ProQuest Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 UMI' U n i v e r s it y o f O k l a h o m a G r a d u a t e C o l l e g e A R a d io X - r a y S e a r c h F o r I ntermediate -A g e S u p e r n o v a e : T u n in g In t o t h e O l d ie s A Dissertation Submitted to the Graduate Faculty In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Christopher J. Stockdale Norman, Oklahoma 2001 UMI Number: 3014513 UMI UMI Microform 3014513 Copyright 2001 by Bell & Howell Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. Bell & Howell Information and Learning Company 300 North Zeeb Road P.O. 00X1346 Ann Arbor, Ml 48106-1346 A R a d io & X - r a y S e a r c h F o r I ntermediate -A g e S u p e r n o v a e : T u n in g I n t o t h e O l d ie s A Dissertation A p p r o v e d f o r t h e D e p a r t m e n t o f P h y s ic s a n d A s t r o n o m y BY J. J. Cowan (Chair) E. Baron l ü fighly O I S. Postawko W. R. Romanshin M. Santos Copyright c 2001, by Christopher J . S t o c k d a l e Ail rights reserved. Acknowledgments Being a student for as long as I have, there are so many people who I should thank for their friendship and assistance. I know that many of those individuals may go unmentioned here, but that in no way diminishes my gratitude to them. My former teachers, especially Michael Priedlander, Loretta “Ole Lady" Har- groder, George Hummer, Rose Laçasse, and Jack Looper: You made learning exciting. Michael P. Rupen, Steven Jones, You-Hua Chu, W. Miller Goss, R. A. Sramek, Christina Lacey, Andrea Prestwich, and my other collaborators: Thank you for assistance and contributions to this work. Ed Baron, Karen Leighly, Susan Postawko, Bill Romanishin, and Mike San­ tos: Your support and guidance as members of my doctoral committee has been outstanding and is deeply appreciated. Kim Milton, David Branch, Dick Henry, Tibor Herczeg, Ron Kantowsld, Jack Cohn, Bruce Mason, Sheena Murphy, Matt Johnson, Kieran Mullen, Stu Ryan, Ryan Doezema, Andy Feldt, Danette Loyd, and the entire Physics & Astronomy faculty and staff: Having been at OU long enough to acquire “tenure”, I thank you for support and encouragement. John J. Cowan: I can’t imagine a better mentor and friend. Without youi- tutelage, I seriously doubt that I would be where I am today. I hope that I will iv be able to do as much, for my students in the future as you have done for me. My sisters, Angelia and Josephine; You are my oldest and dearest friends. May I be able to be of as much help to you as you have been to me. My parents and grandparents: You have made me the person who I am today. I love you all and am grateful for all that you have done. My fellow graduate students along the way, especially Jackie Milingo, Chris Eck, Heidi Morris, Larry Maddox, Pam Jenkins, Scott McCartney, Steve Richichi, Joe Howard, Debra Burris, Giti Khodaparast, Sharon Kennedy, Dean Richardson, Ted Mansell, Terry Caldwell, Lauren Cohen, Whitley Cooke, Doug Canfield, Russ Goodman, Kory Goldammer, Francesca Boffi, Brett McKinney, and Blake Laing: Thanks for your friendship. My dear friends, especially Drew Berke, Jim Mummert, John Dindot, Christy Wells, George & Carla Kober, John, Jeff, & Jason Ottenad, Michael Bell, Adrian & Lucianna Simmons, Stephen Sandifer, Cochanna Rush, Sandra Mah, and Jenn Churchill: Thanks for being there when I needed you. And a special thanks to my friend and “copy editor”, Grettie Bondy. Contents Abstract XI Introduction 1 1.1 Types of Supernovae .................................................................................... 2 1.2 Radio Properties of Supernovae ............................................................... 4 1.2.1 Theory of Radio E m is s io n ............................................................ 6 1.2.2 Theory of X-ray E m is s io n ............................................................ 10 1.2.3 Measurable Results .......................................................................... 14 The Fading Radio Emission From SN 1961V: Evidence for a Type II Peculiar Supernova? 22 2.1 Introduction .................................................................................................... 22 2.2 VLA Observations and Results ................................................................ 25 2.3 VLBI Observations and R esults ................................................................ 27 2.4 Discussion ....................................................................................................... 29 2.5 Conclusions .................................................................................................... 35 The Evolution of Intermediate-aged Radio Supernovae 43 3.1 Introduction................................................................................................... 43 3.2 Observations .................................................................................................... 47 3.2.1 SN 1970G in M ID I ........................................................................... 47 3.2.2 SNe 1923A, 1950B, and 1957D in M 8 3 .................................... 49 3.3 Results.............................................................................................................. 51 3.3.1 SN 19700 ............................................................................................ 51 3.3.2 SN 1957D ............................................................................................ 52 3.3.3 SNe 1923A and 1 9 5 0 B .................................................................... 53 VI 3.3.4 SNe 1945B, 1968L and 1983N ..................................................... 54 3.4 D isc u ssio n ......................................................................................................... 55 X-ray Search For Supernovae 1959D &: 1961V 68 4.1 No X-rays from the Supernovae ............................................................... 68 4.1.1 Observations, Data Reduction, and Results ............................ 69 4.2 A Nuclear X-ray Source in NGC 7331: Evidence for a Massive Black hole ............................................................ 71 4.2.1 Observations and Data Reduction .............................................. 73 4.2.2 Results and Discussion ................................................................... 75 Conclusions 90 5.1 Summary of Results .................................................................................... 90 5.2 Future Plans .................................................................................................... 96 Bibliography 103 A Radio Astronomy With the VLA 114 A.l What is the Very Large A rray? ............................................................... 114 A.2 Calibrating and Flagging VLA Data S ets .............................................. 118 A.3 Imaging VLA d a ta ........................................................................................ 122 B Radio Images 126 v i i List of Tables 2.1 Radio Observations of the Region Near SN 1961V ................................ 36 2.2 Comparison of SN 1961V with Other Radio Supernovae .................... 37 3.1 Observations of Intermediate-Age Radio Supernovae ........................... 59 3.2 Radio Properties of Intermediate-Age Radio Supernovae ................... 60 4.1 Soft X-Ray Supernovae Luminosities Upper L im its ...................... 80 4.2 X-Ray Sources in the Field of NGC 7331 ............................................... 81 4.3 Comparisons of NGC 7331 & Similar X-ray Sources .......................... 82 4.4 Nuclear Positions for NGC 7331 ................................................................. 83 4.5 Core Radio Flux Comparisons of NGC 7331 Sz Similar Sources . 84 4.6 Soft X-ray & 6 cm Radio Flux Ratios for Selected LINERs .... 85 Vlll List of Figures 1.1 Schematic of Radio Emission. Processes in. Supernovae ...................... 11 2.1 VLA radio contour maps at 20 cm (1.5 GHz) and 18 cm (1.7 GHz) of SN 1961V and a neighboring SNR ........................................................ 38 2.2 VLA radio contour maps at 6 cm (4.9 GHz) of SN 1961V and a neighboring SNR ............................................................................................
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