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Measurement of Ionospheric Absorption by the Cosmic Radio Noise Method

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Measurement of Ionospheric Absorption by the Cosmic Radio Noise Method University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Fall 1968 MEASUREMENT OF IONOSPHERIC ABSORPTION BY THE COSMIC RADIO NOISE METHOD J RONALD EARHART Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation EARHART, J RONALD, "MEASUREMENT OF IONOSPHERIC ABSORPTION BY THE COSMIC RADIO NOISE METHOD" (1968). Doctoral Dissertations. 889. https://scholars.unh.edu/dissertation/889 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]. This dissertation has been microiUmed exactly as received 6 9 - 7 0 2 7 EARHART, J. Ronald, 1941- MEASUREMENT OF IONOSPHERIC ABSORPTION BY THE COSMIC RADIO NOISE METHOD. University of New Hampshire, Ph.D., 1968 Physics, general University Microfilms, Inc.. A nn Arbor, Michigan Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. MEASUREMENT OF IONOSPHERIC ABSORPTION BY THE COSMIC RADIO NOISE METHOD ty J. RONALD EARHART B.S. Lebanon Valley College, 1963 M.S. University of New Hampshire, 1966 A THESIS Submitted to the University of New Hampshire In Partial Fulfillment of The Requirements for the Degree of Doctor of Philosophy Graduate School Department of Physics September, 1968 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. This thesis has been examined and approved. PL August- 16 , ■ Date Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGMENTS The author sincerely thanks Dr. Eobert E. Houston, Jr., adviser and friend, who guided this study through its duration. Thanks are due to Dr. C. 0. Bostrom of the Johns Hopkins Applied Physics Laboratory for generously supplying proton data from the satellite 1963 38C. Appreciation is extended to Mrs. Judy Huntley and Mr. Peter Dewdney for data reduction and Mr. Archer Buck for programming assistance. Thanks are extended to Mr. Herbert Scheibel for the drawings and Mrs. Joan Wallingford for the typing. The author sincerly acknowledges the support and encouragement of his wife, Marianne Earhart, during the course of this study. This work was supported by the National Aeronautics and Space Administration under Grant NsG-6lU. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS LIST OF T A B L E S ...................................... vi LIST OF F I G U R E S ...................................... vii ABSTRACT............................................... xii I. INTRODUCTION ........................................ 1 II. THEORY OF THE IONOSPHERE.......................... 6 1. Formation ...................................... 6 a. General Properties ........................ 6 b . Electron Production ..................... 6 c. Electron L o s s e s .......................... 11 d. Chapman L a y e r ............................. l6 e. D-Region.................................... 19 f. E-Region.................................... 2k g. F-negion.................................... 27 2. Electromagnetic Wave Propagation ............ 30 a. Sen-Wyller Formulation ................... 30 b. Simplified Derivation of Ionospheric Birefringence .............. 38 III. THE EXPERIMENTAL TECHNIQUE OFMEASURING COSMIC NOISE A B S O R P T I O N ............................ kO 1. Introduction.................................... Uo 2. Riometer........................................ k2 3. The A n t e n n a .................................... U. Reduction of the Riometer Data to Absorption Values ....................... UT IV. EXPERIMENTAL RESULTS FROM SOLAR INDUCED IONOSPHERIC ABSORPTION STUDY .............. 51 1. Introduction ................................. 51 2. Solar Induced Absorption for 1966 and 1967 . 56 3. Solar Induced Ionospheric Absorption Determined by Sunrise and Sunset at 150 km Reference C u r v e s ................ 73 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. a. General Properties .......................... 73 b. R e s u l t s ................ 77 U. Comparison of the Lover Ionosphere Absorption to a cos^X P i t ..............................108 V. IONOSPHERIC ABSORPTION DURING A DISTURBED PERIOD . 112 1. General Background ............................... 112 2. Theoretical ....................................... 120 a. Calculation of Theoretical Riometer Absorption from a Proton Spectrum . 120 b. Correction of Experimental Broad-Beam Antenna to Pencil-Beam Antenna A b s o r p t i o n ..............................129 3. Experimental....................................... 133 a. Introduction................................... 133 b. Satellite Results .......................... 133 c. Riometer........................................l46 VI. CONCLUSIONS .............................................158 BIBLIOGRAPHY .......................................... l6l APPENDIX A .............................................. 167 APPENDIX B .............................................. 169 APPENDIX C .............................................. 170 APPENDIX D .............................................. 172 APPENDIX E .............................................. 173 APPENDIX F .............................................. 176 APPENDIX G .............................................. 178 APPENDIX H .............................................. 179 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF TABLES Number Page 1. Average Hourly f^Fg in MHz for May, I967 Recorded at Billerica, Massachusetts . 57 2 . Experimental and Theoretical Ionospheric Absorption at 23^2 UT and 2353 UT on September 3, I966 and 0U06 UT on September U, 1 9 6 6 .......................... 151 vi Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OP FIGURES Number Page 1. Block Diagram of a Riometer..................... U3 2. Scatter Plot of EA Values Versus Sidereal Time for a Typical Month of 22 MHz Riometer D a t a ..................... .................... U9 3 . Scatter Plot of EA Values Versus Sidereal Time for the Nighttime Hours in 1967 ......... 59 U. Average Hourly Total Solar Ionospheric Absorption for May, 1966 .............. 63 5 . Average Hourly Total Solar Ionospheric Absorption for July, 1 9 6 6 ....................6U 6. Average Hourly Total Solar Ionospheric Absorption for September, 1966 .................65 7 . Average Hourly Total Solar Ionospheric Absorption for January, 1 9 6 7 ..................66 8. Average Hourly Total Solar Ionospheric Abaerption for May, I9 6 7 ...................... 67 9 . Average Hourly Total Solar Ionospheric Absorption for July, 1 9 6 7 ................ 68 10. Average Hourly Total Solar Ionospheric Absorption for September, 1967 ............69 11. Average Hourly Total Solar Ionospheric Absorption for May, July, and September, 1 9 6 6 .......................................... 70 12. Average Hourly Total Solar Ionospheric Absorption for January, May, July, and September, 1 9 6 7 ............................ 71 1 3 . Scatter Plot of EA Values Versus Sidereal Time •for The Sunrise at 150 km Curve In 1967 . 78 lU. Average Hourly Values of Solar Ionospheric Absorption Determined from the Total Night, Sunrise at I50 km, and Sunset at I50 km Reference Curves for May 1966 79— vii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Number Page 15. Average Hourly Values of Solar Ionospheric Absorption Determined from the Total Night, Sunrise at 150 km, and Sunset at 150 km Reference Curves for July, 196 6 ............................................. 80 1 6 . Average Hourly Values of Solar Ionospheric Absorption Determined from the Total Night, Sunrise at 150 km, and Sunset at 150 km Reference Curves for September, 19 6 6 ................................ 8l 1 7 . Average Hourly Values of Solar Ionospheric Absorption Determined from the Total Night, Sunrise at 150 km, and Sunset at 150 km Reference Curves for January, 196 7 ............................................. 82 1 8 . Average Hourly Values of Solar Ionospheric Absorption Determined from the Total Night, Sunrise at 150 km, and Sunset at 150 km Reference Curves for May, I967 • 83 1 9 . Average Hourly Values of Solar Ionospheric Absorption Determined from the Total Night, Sunrise at 150 km, and Sunset at 150 km Reference Curves for July, 1 9 6 7 ............................................ 8^ 20. Average Hourly Values of Solar Ionospheric Absorption Determined from the Total Night, Sunrise at 150 km, and Sunset at 150 km Reference Curves for September, 1 9 6 7 .......................................... 85 21. Average Hourly Values of Upper and Lower Ionosphere Solar Absorption from the Sunrise Curve in Addition to the Total Solar Ionospheric Absorption for May, 1 9 6 6 .......................................... 87 22. Average Hourly Values of Upper and Lower Ionosphere Solar Absorption from the Sunrise Curve in Addition to the Total Solar Ionospheric Absorption for July, 1966 88 2 3 . Average Hourly Values of Upper and Lower Ionosphere Solar Absorption
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