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Characterizing Terrestrial Planet Formation with Young Debris Disks CHARACTERIZING TERRESTRIAL PLANET FORMATION WITH YOUNG DEBRIS DISKS by Huan Meng BY: = A Dissertation Submitted to the Faculty of the DEPARTMENT OF PLANETARY SCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2014 2 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dis- sertation prepared by Huan Meng entitled Characterizing Terrestrial Planet Formation with Young Debris Disks and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy. Date: 21 November 2014 George Rieke Date: 21 November 2014 Travis Barman Date: 21 November 2014 Joshua Eisner Date: 21 November 2014 Renu Malhotra Date: 21 November 2014 Ilaria Pascucci Final approval and acceptance of this dissertation is contingent upon the candidate's submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. Date: 21 November 2014 Dissertation Director: George Rieke 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. This work is licensed under the Creative Commons Attribution-No Derivative Works 3.0 United States Li- cense. To view a copy of this license, visit http://creativecommons.org/licenses/by- nd/3.0/us/ or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA. SIGNED: Huan Meng 4 ACKNOWLEDGEMENTS This PhD degree does not come easy. Right before coming to Arizona for my PhD study, I was at the turning point of my life. In fall 2005, after a series of personnel changes in the School of Physics, I got clear hints from the school administration and decided to drop out of Peking University, without a bachelor's degree. College admission in China was not based on applications, and retaking the National Higher Education Entrance Exam for new admission is impractical, if not impossible. The Chinese society was not as tolerant as in America when it came to personal success regarding higher education. The setbacks appeared more overwhelming in that social circumstance. Nevertheless, I was seriouly determined not to give up my dream for science. This extraordinary road was never easy, but luckily, I was not alone. I am grateful for all the people I met and dealt with during this endeavor, who understood and who did not, who stayed and who left, who encouraged me and who sneered at me { they made my life as dramatic as in a novel. In particular, I would like to thank Jin Zhu, former professor at the National Astronomical Observatories of China and current director of Beijing Planetarium, whose kind and rigorous mentoring changed my life; David Jewitt, whose generous support almost led me to Hawaii but finally helped me land in Arizona; Michael Drake, former department head of Planetary Sciences, who seriously took my unusual case and pushed it forward; Roger Yelle, whose efforts gave me the opportunity that I turned to this dissertation today; and Jay Melosh, who chaired the Graduate Academic Advising Committee and believed that they \did the right thing" to offer me a position in this PhD program. Research has been the theme throughout my PhD years. I am extremely grateful for George Rieke, whose responsible and tireless mentoring thoughout the years kept me inspired and humble on my way to being a real scientist; and Peter Plavchan, who made my fellowship experience at Caltech eye-opening and enjoyable. I would also like to thank my other mentors and collaborators, especially Kate Su, Wiphu Rujopakarn, Carey Lisse, and David Stevenson. This dissertation is made possible by their brilliant ideas and insightful discussions. The six plus years in Arizona mean a lot to me. I am especially thankful for my parents, whose love have accompanied me wherever I go; Jing Han, whose belief and encouragement made me who I am today; Jun Li, who has been through a lot with me; and Xiaodong Huang, for all the precious love and touching support. I also wish to thank Fuyan Bian, Fan Guo, Jie Min, and all my other friends for the wonderful and irreplaceable Arizona experience. 5 DEDICATION To whom I love and what I work for. To space, time, and extraterrestrial life. 6 TABLE OF CONTENTS LIST OF FIGURES................................9 LIST OF TABLES................................. 10 ABSTRACT.................................... 11 CHAPTER 1 ABC (Attribution, Background, and Context)......... 13 1.1 Birth Environment of Terrestrial Planets................ 13 1.2 Background Physics and Techniques................... 15 1.2.1 Dating Young Stars........................ 15 1.2.2 Fate of Small Dust Particles................... 18 1.2.3 Spectral Analysis of Dust Mineralogy.............. 20 1.3 Current Progress and Organization of This Dissertation........ 22 CHAPTER 2 Persistence of Debris Disks During Terrestrial Planet Formation 24 2.1 Introduction................................ 24 2.2 Cluster and Association Membership.................. 25 2.2.1 Comparison of Membership Lists................ 29 2.3 Data Processing.............................. 30 2.3.1 Source Matching and Photometry................ 30 2.3.2 Determination of Relative Excesses at 24 µm.......... 33 2.4 Time Evolution of 24 µm Excess..................... 36 2.4.1 \Disk" Definition......................... 36 2.4.2 Evolution of Disk Frequency................... 38 2.4.3 Persistence of Massive Debris Disks to 20-25 Myr....... 42 2.5 Conclusions................................ 43 CHAPTER 3 Variability of the Infrared Excess of Extreme Debris Disks.. 46 3.1 Introduction................................ 46 3.2 Data.................................... 47 3.3 Discussion................................. 52 3.4 Conclusion................................. 57 CHAPTER 4 Case Study of ID8: Large Impacts around a Solar Analog Star in the Era of Terrestrial Planet Formation.................. 59 4.1 Observations and Data Reduction.................... 59 7 TABLE OF CONTENTS { Continued 4.1.1 Optical Observations and Photometry............. 59 4.1.2 Spitzer Observations and Data Analysis............. 60 4.2 Analysis of the Debris Disk Light Curve................ 65 4.2.1 Long-Term Decay......................... 65 4.2.2 Periodicity............................. 68 4.3 Physical and Dynamical Interpretation................. 72 4.3.1 Observational Constraints.................... 72 4.3.2 Numerical Simulations...................... 73 4.4 Scale of the Impact............................ 77 4.5 Remarks.................................. 79 CHAPTER 5 Planetary Collisions outside the Solar System: Time Domain Characterization of Extreme Debris Disks.................. 81 5.1 Observations and Data Analysis..................... 81 5.1.1 Targets.............................. 81 5.1.2 Spitzer Observations and Data Reduction............ 84 5.1.3 Analysis Methods......................... 86 5.2 Discussion of Individual Stars...................... 89 5.2.1 P1121............................... 89 5.2.2 HD 15407A............................ 94 5.2.3 HD 23514AB........................... 97 5.2.4 HD 145263............................ 99 5.2.5 BD+20 307AB.......................... 102 5.3 Comparisons and Implications...................... 105 5.3.1 Incidence of terrestrial planets around solar-like stars..... 105 5.3.2 Are disk composition and evolution correlated?........ 106 5.3.3 What causes the rapid decay after an impact?......... 110 5.4 Conclusions................................ 111 CHAPTER 6 Summary and Future Studies.................. 112 6.1 Summay and Conclusions........................ 112 6.2 Future Studies............................... 113 6.2.1 Protoplanetary Disk Dissipation at 24 µm........... 113 6.2.2 Observing Extreme Debris Disks in Real-time......... 114 6.2.3 Modeling Extrasolar Planetary Impacts............. 116 APPENDIX A Membership Identification for NGC 2244 and NGC 1333... 117 A.0.4 NGC 2244............................. 117 A.0.5 NGC 1333............................. 118 8 TABLE OF CONTENTS { Continued APPENDIX B Filtering out Bad Photometry on Complicated Sky Backgrounds122 APPENDIX C Error Distribution of Relative Excess.............. 127 APPENDIX D Optical Monitoring of the Host Stars of Extreme Debris Disks 130 D.0.6 Observations and Data Reduction................ 130 D.0.7 P1121............................... 131 D.0.8 HD 15407A............................ 133 D.0.9 HD 23514AB........................... 133 D.0.10 BD+20 307AB.......................... 135 REFERENCES................................... 136 9 LIST OF FIGURES 2.1 24 µm disk frequencies as a function of stellar age........... 39 2.2 24 µm disk frequencies as a function of stellar age for stars ≥1.2 M . 41 2.3 Frequency of debris disks......................... 44 3.1 SED of ID8................................ 48 3.2 SED of HD 23514............................. 49 4.1 Optical light curve of ID8........................ 61 4.2 Color-magnitude diagram of ID8..................... 64 4.3 Infrared light curve of ID8.......................
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