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Dark Matter Halo Mergers and Quasars

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Dark Matter Halo Mergers and Quasars University of Pennsylvania ScholarlyCommons Publicly Accessible Penn Dissertations Spring 2010 Dark Matter Halo Mergers and Quasars Jorge Moreno University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/edissertations Part of the Cosmology, Relativity, and Gravity Commons, and the External Galaxies Commons Recommended Citation Moreno, Jorge, "Dark Matter Halo Mergers and Quasars" (2010). Publicly Accessible Penn Dissertations. 177. https://repository.upenn.edu/edissertations/177 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/edissertations/177 For more information, please contact [email protected]. Dark Matter Halo Mergers and Quasars Abstract The formation and evolution of galaxies and the supermassive black holes they harbor at their nuclei depends strongly on the merger history of their surrounding dark matter haloes. First we developed a semi-analytic algorithm that describes the merger history tree of a halo. The following tests were performed: the conditional mass function, the time and mass distributions at formation, and the time distribution of the last major merger. We provide a model for the creation rate of dark matter haloes, informed by both coagulation theory and the modified excursion set approach with moving barriers. A comparison with N-body simulations shows that our square-root barrier merger rate is significantly better than the standard extended Press-Schechter rate used in the literature. The last chapter is dedicated to a simple model of quasar activation by major mergers of dark matter haloes. The model consists of two main ingredients: the halo merger rate describing triggering, and a quasar light curve, which tracks the evolution of individual quasars. In this model, the mass of the seed black hole at triggering is assumed to be a fixed fraction of its mass at the peak luminosity. The light curve has two components: an exponential ascending phase and a power-law descending phase that depends on mass of the host. We postulate a self-regulation condition between the peak luminosity of the active galactic nucleus (AGN) and the mass of the host halo at triggering. This type of model for quasar evolution is at the heart of the latest semianalytic models (SAMs) of galaxy formation and it is therefore definitely worth studying in some detail. By carefully revisiting some of the main issues linked to this approach, we were able to derive several interesting and physically meaningful constraints regarding black hole evolution. We expect simple, yet observationally-constrained models like ours to play a central role in future models of galaxy formation. Degree Type Dissertation Degree Name Doctor of Philosophy (PhD) Graduate Group Physics & Astronomy First Advisor Ravi K. Sheth Keywords galaxies, black holes, quasars, haloes Subject Categories Cosmology, Relativity, and Gravity | External Galaxies This dissertation is available at ScholarlyCommons: https://repository.upenn.edu/edissertations/177 DARK MATTER HALO MERGERS AND QUASARS Jorge Moreno A DISSERTATION in Physics and Astronomy Presented to the Faculties of the University of Pennsylvania in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy 2010 Supervisor of Dissertation Ravi K. Sheth, Professor of Physics and Astronomy Graduate Group Chairman Ravi K. Sheth, Professor of Physics and Astronomy Dissertation Committee Gary Bernstein, Professor of Physics and Astronomy Adam Lidz, Assistant Professor of Physics and Astronomy Andrea J. Liu, Professor of Physics and Astronomy Gordon T. Richards, Assistant Professor of Physics Dedication This thesis is dedicated to my wife Viridiana, and our children Camila and Mateo. You are the best thing a person can have. Thank you for your love, patience and encouragement during these difficult years and for giving meaning to my life. ii Acknowledgments To break the tradition, I wish to thank the most important people in my life first: my wonderful wife Viridiana Moreno and our children Camila and Mateo, to whom this thesis is dedicated. I would also like to thank my parents Martha Soto and Juan Moreno for doing everything in their power so I had the opportunities they could not have. Also to my brothers Hector and Juan Ernesto, for always having my back. Likewise, I would like to thank Rafael Moreno, Irene Gomez, Vianney Moreno, Demian Cortes, Jacqueline Ibarrola, Sandra Arvezu, little Paulo – and of course, the rest of the family (too many to mention individually). It is my pleasure to thank my thesis advisor, Ravi Sheth. My father always says that the two most important decisions in a person’s life is choosing who they are going to marry, and choosing their career. I would replace the latter with “choosing the right Ph.D advisor”. I personally could not have chosen a better mentor. There are not enough pages, or years, to show my gratitude to Ravi. I also want to thank Francesco Shankar and Carlo Giocoli for all their support, encouragement, and the wonderful opportunity of writing papers together. Also I wish to thank iii my other collaborators: Bepi Tormen, David Weinberg, Raul Angulo, Cheng Li, Martin Crocce, and Federico Marulli. I thank Beth Willman for her encouragement, guidance, and friendship during these last few difficult months. I wish to thank Gary Bernstein, Adam Lidz, Andrea Liu, Gordon Richards, and of course, Ravi Sheth, for agreeing to serve as committee members, and for tak- ing the time and dedication to read this rather long thesis. Also to my professors for imparting their knowledge and advice, including Gary Bernstein, Mariangela Bernardi, Bhuvnesh Jain, Mark Devlin, Masao Sato, Vijay Balasubramanian, Burt Ovrut, Mirjam Cvetic, Mark Gulian, Randy Kamien, Joe Kroll, Phil Nelson, Paul Langacker, and Fay Ajzenberg-Selove. To CONACyT-Mexico, and Grant 2002352 from the US-Israel BSF for funding. Also to colleagues at Haverford College for their constant support, especially Walter Smith, Steve Boughn, and Bruce Partridge for their mentoring; and Beth Willman, Stephon Alexander, Peter Love, Anna Sajina, Chema Diego, Adi Zolotov, and Aurelia Gomez Unamuno for their friendship. To folks at Cinvestav for making my move to Penn possible, including my former advi- sor Hugo Compean, and my professors Arnulfo Zepeda, Juan Jose Godina, Denjoe O’Connor, Tonatiuh Matos, Eloy Ayon, Mauricio Carvajal, Gerardo Herrera, Piotr Kielanowski, Masiej Pzranowski, Gabriel Lopez, Jorge Hirsch, Jose Mendez, and Miguel Angel Perez. But mostly to Guillermo Moreno, Jerzy Plebanski and Au- gusto Garcia, may they rest in peace. Also, my friends Ramon Casta˜neda, Armando Perez, Jose Manuel Lara Bauche, Argelia Bernal, Carlos Chavez, Jorge Mercado, iv Juan Barranco, Idrish Huet, Eduard de la Cruz Burelo, Ildefonso Leon, Americo Rodriguez and Pedro Podesta. To my friends at Penn, including Joey Hyde, Mike Fischbein, Andres Plazas, Zhaoming Ma, Jacek Guzik, Matt Martino, Graziano Rossi, Dan Swetz, Ed Chapin, Amitai Bin-Nun, Tsz Yan Lam, Laura Marian, Reiko Nakajima, Federica Bianco, Greg Dobler, Josko Kirigin, Alex Borisov, Hite and Willis Geffert, Dutch Ratliff, and many others for the great years together and their friendship. I wish to thank all my teachers for encouraging me, especially Mrs. and Mr. Blackwood, Mr. Erdman, Ms. Faridian, Mr. Guember, Ms. Kahn, Mr. Lange, Ms. Hooper, Ms. Komatsu, Ms. Martin, Ms. O’Connell, Ms. Scharf, Mr. Silverman, Mr. Taylor, Ms. Votto, and maestras Eva, Edith and Maria Luisa. And a few good friends that have supported me during the years: Noah Bray-Ali, Adam Ferrell, Alex Prieto and Rosa Elia Victorio. Parts of these work were done with the direct help, suggestions, and inputs of Silvia Bonoli, Marcella Brusa, Anca Constantin, Onsi Fakhouri, Joey Hyde, Avi Loeb, Eyal Neistein, Robert Smith and Yue Shen. Many others, listed below, contributed indirectly in many ways. I wish to thank the following people for the insightful conversations, comments, questions, encouragement and hospitality during my ‘talk tour’ where presenta- tions of this work were delivered. Although it is a rather long list, the input from every single one of you has contributed to make me a better scientist. At Cin- vestav: Eduard de la Cruz Burelo, Miguel Garcia, Isaac Hernandez, Miguel Angel v Perez, Tonatiuh Matos, Arnulfo Zepeda, At UNAM: Vladimir Avila-Reese, Anto- nio Peimbert, Octavio Valenzuela. At INAOE: Vahram Chavushyan, David Hughes, Hector Ibarra, Omar Lopez Cruz, Divakara Mayya, Alfredo Monta˜na. At Colgate: Thomas Balonek, Jeff Bary. At Williams: Marek Demianski, Karen Kwitter, Steve Souza. At Texas: Guillermo Blanc, Amy Forestell, Martin Gaskell, Karl Gebhardt, Donghui Jeoung, Jarrett Johnson, Jun Koda, Eiichiro Komatsu, Randi Ludwig, Yi Mao, Irina Marinova, Milos Milosavljevic, Paul Shapiro, Matashoshi Shoji, Chalence Timer, Berverly Wills. At Harvard: Federica Bianco, Laura Blecha, Anca Con- stantin, Claude-Andre Faucher-Guiguere, Ryan Hickox, Avi Loeb, Ryan O’Leary, Adam Lidz, Matt Mcquinn, Ramesh Narajan, Jonathan Pritchard, Jaiyul Yoo, Matthias Zaldarriaga. At UC Santa Barbara: Nicola Bennert, Peng Oh, Tommaso Treu. At Stanford: Marcelo Alvarez, Michael Busha, Brian Gerke, Nelima Sehgal, Louie Strigari, Risa Wechsler, Chen Zheng. At UC Berkeley: Kevin Bundy, Jor- dan Carlson, Joanne Cohn, Marina Cortes, Roland De Putter, Marc Davis, Shirley Ho, Phil Hopkins, Alexie Leauthaud, Eric Linder, Chung-Pei Ma, Reiko Nakajima, Jonathan Pober, Linda Strubbe, Tristan Smith, George Smoot, Andrew Wetzel,
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