Surveying Transient Host Galaxies with ASAS-SN 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 Scott Brown Jr. Graduate Program in Astronomy The Ohio State University 2018 Dissertation Committee: Professor Krzysztof Z. Stanek, Advisor Professor Christopher S. Kochanek Professor Paul Martini Copyright by Jonathan Scott Brown Jr. 2018 Abstract The technological advances of the recent years have allowed for the proliferation of relatively inexpensive charge-coupled devices (CCDs) and other imaging hardware that has revolutionized modern astronomy. The burgeoning field of transient astronomy is perhaps the largest benefactor of these advances, and as a result, high cadence, all-sky surveys are becoming a reality. New transient phenomena are discovered and studied in depth on a regular basis, and the datasets of “normal” transients are becoming richer by the day. However, transient phenomena are intimately connected to their environment, and understanding this connection can provide insight that the study of transient phenomenology alone cannot. In this dissertation, I leverage the statistical power of modern all-sky surveys to investigate the nature of transients, the properties of their host galaxies, as well as the techniques and tools we use to study both. ii Dedication To motorcycle maintenance. iii Acknowledgments I am indebted to the OSU Department of Astronomy for encouraging such a lively and collegial environment in which to learn and grow as a scientist, as well as the OSU Graduate School for providing support to conduct my research. I’d especially like to thank the members of my committee. I am immensely grateful for Professor Krzysztof Z. Stanek’s mentorship and his ability to identify what is important, and how to explain it in a way that people can connect to. I am also grateful for his witty title suggestions. I am thankful to Professor Christopher S. Kochanek for his truly rapid and informative feedback on any questions I’ve had. I must also thank him for the many trips to the LBT, and for being a counterweight to Professor Stanek’s wit. I am grateful to Professor Paul Martini for his role early on in my graduate student career, especially for his guidance on writing and editing. I thank Professor Richard W. Pogge and Kevin Croxall for introducing me to spectroscopy with MODS, which ultimately paved the way for the rest of my time here at OSU. I owe David Will many thanks for a near seamless computing experience for the 5 years I’ve spent here. I thank Office 4k members both past and present, including honorary member Greg Simmonian for his frequent banter and occasional admonishment. In particular, I’d like to thank Tom Holoien for being a iv great friend (but don’t think for a second I’ve forgotten about Sevastopol), colleague, and brewery enthusiast. Always remember, as far as the official fantasy football record is concerned, we are equals. Job Office, thank you all for making this past year much less stressful than it otherwise would have been. I am also immensely grateful to the members of the department that came before me, especially Ben Shappee and Brett Andrews, whose own efforts made much of my research possible. Finally, I owe many thanks to my friends from that school up north; you’ve each been an inspiration in one form or another, so thanks n’at. v Vita December 11, 1990 ............. Born – Burlington, VT, USA B.S., Astronomy & Astrophysics 2013 – 2015..................... University of Michigan Graduate Teaching Associate 2013 – 2016..................... The Ohio State University M.S., Astronomy 2016............................ The Ohio State University Graduate Research Associate 2016 – 2017..................... The Ohio State University Presidential Fellow 2017 – 2018..................... The Ohio State University Allan Markowitz Award in Observational Astronomy 2018............................ The Ohio State University Publications Research Publications 1. J. S. Brown, C. S. Kochanek, T. W.-S. Holoien, K. Z. Stanek, K. Auchettl, B. J. Shappee, J. L. Prieto, N. Morrell, E. Falco, J. Strader, L. Chomiuk, R. Post, S. Villanueva Jr., S. Mathur, S. Dong, P. Chen, and S. Bose, “The ultraviolet spectroscopic evolution of the low-luminosity tidal disruption event iPTF16fnl”, Monthly Notices of the Royal Astronomical Society, 473, 1130, (2018) vi 2. T. W.-S. Holoien, J. S. Brown, K. Z. Stanek, C. S. Kochanek, B. J. Shappee, J. L. Prieto, S. Dong, J. Brimacombe, D. W. Bishop, S. Bose, J. F. Beacom, D. Bersier, P. Chen, L. Chomiuk, E. Falco, D. Godoy-Rivera, N. Morrell, G. Pojmanski, J. V. Shields, J. Strader, M. D. Stritzinger, T. A. Thompson, P. R. Wo´zniak, G. Bock, P. Cacella, E. Conseil, I. Cruz, J. M. Fernandez, S. Kiyota, R. A. Koff, G. Krannich, P. Marples, G. Masi, L. A. G. Monard, B. Nicholls, J. Nicolas, R. S. Post, G. Stone, and W. S. Wiethoff, “The ASAS-SN bright supernova catalogue - III. 2016”, Monthly Notices of the Royal Astronomical Society, 471, 4966, (2017) 3. C. S. Kochanek, M. Fraser, S. M. Adams, T. Sukhbold, J. L. Prieto, T. M¨uller, G. Bock, J. S. Brown, S. Dong, T. W.-S. Holoien, R. Khan, B. J. Shappee, and K. Z. Stanek, “Supernova progenitors, their variability and the Type IIP Supernova ASASSN-16fq in M66”, Monthly Notices of the Royal Astronomical Society, 467, 3347, (2017) 4. T. W.-S. Holoien, J. S. Brown, K. Z. Stanek, C. S. Kochanek, B. J. Shappee, J. L. Prieto, S. Dong, J. Brimacombe, D. W. Bishop, U. Basu, J. F. Beacom, D. Bersier, P. Chen, A. B. Danilet, E. Falco, D. Godoy-Rivera, N. Goss, G. Pojmanski, G. V. Simonian, D. M. Skowron, T. A. Thompson, P. R. Wo´zniak, C. G. Avila,´ G. Bock, J.-L. G. Carballo, E. Conseil, C. Contreras, I. Cruz, J. M. F. And´ujar, Z. Guo, E. Y. Hsiao, S. Kiyota, R. A. Koff, G. Krannich, B. F. Madore, P. Marples, G. Masi, N. Morrell, L. A. G. Monard, J. C. Munoz-Mateos, B. Nicholls, J. Nicolas, R. M. Wagner, and W. S. Wiethoff, “The ASAS-SN bright supernova catalogue - II. 2015”, Monthly Notices of the Royal Astronomical Society, 467, 1098, (2017) 5. M. M. Fausnaugh, C. J. Grier, M. C. Bentz, K. D. Denney, G. De Rosa, B. M. Peterson, C. S. Kochanek, R. W. Pogge, S. M. Adams, A. J. Barth, T. G. Beatty, A. Bhattacharjee, G. A. Borman, T. A. Boroson, M. C. Bottorff, J. E. Brown, J. S. Brown, M. S. Brotherton, C. T. Coker, S. M. Crawford, K. V. Croxall, S. Eftekharzadeh, M. Eracleous, M. D. Joner, C. B. Henderson, T. W.-S. Holoien, K. Horne, T. Hutchison, S. Kaspi, S. Kim, A. L. King, M. Li, C. Lochhaas, Z. Ma, F. MacInnis, E. R. Manne-Nicholas, M. Mason, C. Montuori, A. Mosquera, D. Mudd, R. Musso, S. V. Nazarov, M. L. Nguyen, D. N. Okhmat, C. A. Onken, B. Ou-Yang, A. Pancoast, L. Pei, M. T. Penny, R. Poleski, S. Rafter, E. Romero-Colmenero, J. Runnoe, D. J. Sand, J. S. Schimoia, S. G. Sergeev, B. J. Shappee, G. V. Simonian, G. Somers, M. Spencer, D. A. Starkey, D. J. Stevens, J. Tayar, T. Treu, S. Valenti, J. Van Saders, S. Villanueva Jr., C. Villforth, Y. Weiss, H. Winkler, and W. Zhu, “Reverberation Mapping of Optical Emission Lines in Five Active Galaxies”, The Astrophysical Journal, 840, 97, (2017) 6. J. S. Brown, T. W.-S. Holoien, K. Auchettl, K. Z. Stanek, C. S. Kochanek, B. J. vii Shappee, J. L. Prieto, and D. Grupe, “The Long Term Evolution of ASASSN-14li”, Monthly Notices of the Royal Astronomical Society, 466, 4904, (2017) 7. L. Pei, M. M. Fausnaugh, A. J. Barth, B. M. Peterson, M. C. Bentz, G. De Rosa, K. D. Denney, M. R. Goad, C. S. Kochanek, K. T. Korista, G. A. Kriss, R. W. Pogge, V. N. Bennert, M. Brotherton, K. I. Clubb, E. Dalla Bont`a, A. V. Filippenko, J. E. Greene, C. J. Grier, M. Vestergaard, W. Zheng, S. M. Adams, T. G. Beatty, A. Bigley, J. E. Brown, J. S. Brown, G. Canalizo, J. M. Comerford, C. T. Coker, E. M. Corsini, S. Croft, K. V. Croxall, A. J. Deason, M. Eracleous, O. D. Fox, E. L. Gates, C. B. Henderson, E. Holmbeck, T. W.-S. Holoien, J. J. Jensen, C. A. Johnson, P. L. Kelly, S. Kim, A. King, M. W. Lau, M. Li, C. Lochhaas, Z. Ma, E. R. Manne-Nicholas, J. C. Mauerhan, M. A. Malkan, R. McGurk, L. Morelli, A. Mosquera, D. Mudd, F. Muller Sanchez, M. L. Nguyen, P. Ochner, B. Ou-Yang, A. Pancoast, M. T. Penny, A. Pizzella, R. Poleski, J. Runnoe, B. Scott, J. S. Schimoia, B. J. Shappee, I. Shivvers, G. V. Simonian, A. Siviero, G. Somers, D. J. Stevens, M. A. Strauss, J. Tayar, N. Tejos, T. Treu, J. Van Saders, L. Vican, S. Villanueva Jr., H. Yuk, N. L. Zakamska, W. Zhu, M. D. Anderson, P. Ar´evalo, C. Bazhaw, S. Bisogni, G. A. Borman, M. C. Bottorff, W. N. Brandt, A. A. Breeveld, E. M. Cackett, M. T. Carini, D. M. Crenshaw, A. De Lorenzo-C´aceres, M. Dietrich, R. Edelson, N. V. Efimova, J. Ely, P. A. Evans, G. J. Ferland, K. Flatland, N. Gehrels, S. Geier, J. M. Gelbord, D. Grupe, A. Gupta, P. B. Hall, S. Hicks, D. Horenstein, K. Horne, T. Hutchison, M. Im, M. D. Joner, J. Jones, J. Kaastra, S. Kaspi, B. C. Kelly, J. A. Kennea, M. Kim, S. C. Kim, S. A. Klimanov, J. C. Lee, D. C. Leonard, P. Lira, F. MacInnis, S. Mathur, I. M. McHardy, C. Montouri, R.