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The Formation and Evolution of Disk Galaxies

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The Formation and Evolution of Disk Galaxies The Formation and Evolution of Disk Galaxies Dissertation Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Jonathan C. Bird, M.S., B.S. Graduate Program in Astronomy The Ohio State University 2012 Dissertation Committee: Professor David H. Weinberg, Advisor Professor Jennifer A. Johnson Professor Marc H. Pinsonneault Copyright by Jonathan C. Bird 2012 ABSTRACT Current and next generation surveys of the Milky Way promise to revolutionize our observational perspective of the Galaxy. My dissertation uses a suite of N-body and SPH simulations of disk galaxies to make testable predictions of the assembly history of the Milky Way and identify observational probes that take advantage of the forthcoming data. APOGEE, an infrared survey of the Galaxy and a component of the SDSS-III, will measure the distance, radial velocity, and multi-element chemistry of ∼ 105 stars located throughout the Galaxy, making it particularly well suited for comparison with simulations. We first use a fuel-consumption argument to constrain the integrated luminosity of the TP-AGB phase; the energy release in this phase is a major uncertainty in stellar population synthesis models. Our initial numerical investigation explores how the minor mergers expected in ΛCDM and inherent properties of stellar disks affect the dynamics of stellar radial migration- an essential ingredient in understanding the evolution of the Milky Way and disk galaxies in general. We discover that the resonances and mechanisms responsible for migration are different in isolated and satellite-bombarded galaxies, resulting in distinct migration patterns and potential observational signatures of accretion ii events. Continuing our development of tools to describe the chemo-dynamics of the disk, we construct statistics to measure overdensities and characterize outliers in the distance, radial velocity projection of phase space. I discuss mock APOGEE observations of our numerical simulations and demonstrate that our statistics can begin to discriminate between significant galaxy formation mechanisms given the data available in the near term. Finally, we use a state of the art cosmological simulation to describe the evolution of mono-age stellar populations and their eventual assembly into a galaxy resembling the Milky Way. Galaxy formation theory faces the exciting challenge of an unprecedented level of statistical scrutiny: imminent and ongoing surveys such as SEGUE, RAVE, APOGEE, LAMOST, and HERMES offer an extraordinary opportunity to unravel the formation history of the Milky Way. iii To my number one fan, always. iv ACKNOWLEDGMENTS I would never consider a work representing the culmination of a significant fraction of my life as an independent endeavor. None of this would have been possible if not for my advisor, David Weinberg. His thoughtfulness and vision have led me down an exciting path of scientific investigation; I am sure I will continue to learn from our interactions long after I leave Ohio State. I owe a special thanks to Stelios Kazantzidis; I have enjoyed our deep collaboration. The Ohio State Astronomy faculty have had a strong, positive influence on my growth as a scientific researcher and as a person. In particular, I thank Professors Paul Martini, Kris Stanek, Marc Pinsonneault, Jennifer Johnson, Scott Gaudi, and Todd Thompson. I have not made it to this point without a great deal of help. A huge thank you to my Mother: I really appreciate that whole “giving birth to me” thing, the countless sacrifices you made to raise me, and your unwavering support of my passion. To my sister, Katrina, thank you for always telling me to “kick some astro-butt”; I am so thankful for deep connection and for how much I have learned through our relationship. Thank you for rooting me on Natasha, my sister, and Narayan, her husband; and thank you for your help in obtaining this opportunity. A v bittersweet, deep thank you to my now departed Father; thank you for showing me what a man could become. Thank you family, I love you all. I am incredibly lucky to have so many wonderful friends who are constant sources of inspiration, joy, and support. To the other members of the five- Kevin, Frankie, Ray, and Pat: thank you for what is turning into a lifetime of friendship; our brotherhood has carried me more than you know. Tony, thanks for the caped adventures; Kamilee, thank you for understanding the 20 year-old me. To the amazing set of friends I have accumulated throughout graduate school, especially Jason, Rob, Linda, Kelly, Kate, and Roberto: you all rock and you have made this time so special. To the incomparable Katie “Tizzle B”: I think “I wanna dance with somebody” sums it up best. Finally, to the love of my life, Emily: Thank you for shining so brightly that I could find my way even during the darkest days that I have ever known. vi VITA April 30, 1981 . Born – Santa Monica, Califonia, United States 2003 ........................... B.S. Physics, California Institute of Technology 2006 – 2007 . Distinguished University Fellow, The Ohio State University 2007 – 2011 .................... Graduate Teaching and Research Associate, The Ohio State University 2011 – 2012 . Distinguished University Fellow, The Ohio State University PUBLICATIONS Research Publications 1. Nidever, David L., Zasowski, Gail, Majewski, Steven R., Bird, Jonathan C., and 32 coauthors, “The Apache Point Observatory Galactic Evolution Exper- iment: First Detection of High-velocity Milky Way Bar Stars”, ApJ, 755L, 25N, (2012). 2. J. C. Bird, S. Kazantzidis,D. H. Weinberg,“Radial Mixing in Galactic Disks: The Effects of Disk Structure and Satellite Bombardment, MNRAS, 420, 913B, (2012). 3. C.J. Grier and 38 coauthors including Jonathan C. Bird, “A Reverbera- tion Lag for the High-Ionization Component of the Broad Line Region in the Narrow-Line Seyfert 1 Mrk 335”, ApJ, 744L, 4G2011, (2012). 4. Jonathan C. Bird and Marc H. Pinsonneault, “A Bound on the Light Emitted During the TP-AGB Phase”, ApJ, 733, 81B, (2011). 5. Y.S. Lee, T.C. Beers, D. An, Z. Ivezic, A. Just, C. M. Rockosi, H. L. Morrison, J. A. Johnson, R. Schonrich, J. Bird, B. Yanny, P. Harding, H. J. vii Rocha-Pinto, “Formation and Evolution of the Disk System of the Milky Way: [alpha/Fe] Ratios and Kinematics of the SEGUE G-Dwarf Sample”, ApJ, 738, 187L, (2011). 6. K. D. Denney and 42 coauthors including J. C. Bird, “Reverberation Mapping Measurements of Black Hole Masses in Six Local Seyfert Galaxies”, ApJ, 721, 715D, (2010). 7. C. Villforth and 50 coauthors including J. C. Bird, “Variability and sta- bility in blazar jets on time-scales of years: optical polarization monitoring of OJ 287 in 2005-2009”, MNRAS, 402, 2087, (2010). 8. Kelly D. Denney and 42 coauthors including Jonathan C. Bird, “Diverse Kinematic Signatures From Reverberation Mapping of the Broad-Line Regions in Active Galactic Nuclei”, ApJL, 704, L80, (2009). 9. J. C. Yee, A. Udalski, T. Sumi, S. Dong, S. KozÃlowski, J. C. Bird, and 80 coauthors, “Extreme Magnification Microlensing Event OGLE-2008-BLG-279: Strong Limits on Planetary Companions to the Lens Star”, ApJ, 703, 2082, (2009). 10. K. D. Denney and 32 coauthors including J. C. Bird, “A Revised Broad- Line Region Radius and Black Hole Mass for the Narrow-Line Seyfert 1 NGC 4051”, ApJ, 702, 1353, (2009). 11. M. J. Valtonen and 43 coauthors including J. C. Bird, “Tidally Induced Outbursts in OJ 287 during 2005-2008”, ApJ, 698, 781, (2009). 12. J. C. Bird, K. Z. Stanek, and J. L. Prieto, “Using Ultra Long Period Cepheids to Extend the Cosmic Distance Ladder to 100 Mpc and Beyond”, ApJ, 695, 874, (2009). 13. C. J. Grier and 16 coauthors including J. Bird, “The Mass of the Black Hole in the Quasar PG 2130+099”, ApJ, 688, 837, (2008). 14. J. C. Bird, P. Martini, and C. Kaiser, “The Lifetime of FR II Sources in Groups and Clusters: Implications for Radio-Mode Feedback”, ApJ, 676, 147, (2008). FIELDS OF STUDY Major Field: Astronomy viii Table of Contents Abstract..................................... ii Dedication.................................... iv Acknowledgments................................ v Vita ....................................... vii ListofTables .................................. xii ListofFigures.................................. xiii Chapter 1 Introduction ............................ 1 1.1 ContextandScope ............................ 4 Chapter 2 A Bound on the Light Emitted During the TP-AGB Phase 7 2.1 SampleandMethods ........................... 9 2.1.1 White Dwarf Samples and Final Masses . 9 2.1.2 ClusterParameters . 11 2.1.3 InitialMasses ........................... 12 2.1.4 ClusterAverages ......................... 16 2.1.5 Fraction of Core Growth in the TP-AGB Phase . 17 2.1.6 Fuel Consumption: Mass-Light Coupling . 17 2.2 Results................................... 19 2.2.1 Initial Final Mass Relation . 19 ix 2.2.2 CoreGrowthintheTP-AGBPhase. 20 2.2.3 Fuel from Stellar Core Growth . 22 2.2.4 Fuel from Stellar Yields . 23 2.3 SummaryandDiscussion......................... 24 Chapter 3 Radial Mixing in Galactic Disks: The Effects of Disk Structure and Satellite Bombardment ................. 35 3.1 Methods.................................. 39 3.1.1 IsolatedDiskModels ....................... 39 3.1.2 PerturbedDiskModels. 41 3.1.3 NumericalParameters . 42 3.2 Results................................... 44 3.2.1 RadialMigration ......................... 45 3.2.2 OrbitalCharacteristics . 48 3.2.3 SolarAnnulus........................... 54 3.3 SummaryandDiscussion........................
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