Photometric techniques for Exoplanet detection: The construction and deployment of the KELT-South telescope Town Rudolf Bruwer Kuhn October 2014 Cape of A project submittedUniversity in partial fulfilment of the requirements for the degree PhD. in the Department of Astronomy UNIVERSITY OF CAPE TOWN Supervisors: Prof. P. A. Whitelock and Dr. J. W. Menzies In Collaboration with Dr. J. A. Pepper at Lehigh University and Prof. K. G. Stassun at Vanderbilt University The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgementTown of the source. The thesis is to be used for private study or non- commercial research purposes only. Cape Published by the University ofof Cape Town (UCT) in terms of the non-exclusive license granted to UCT by the author. University Town Cape of University Abstract In this thesis I present the work I performed during the initial construction and deployment of the second telescope in the KELT project and I report the results of the search for tran- siting exoplanets and variable stars using one of the first commissioning datasets obtained with the telescope. The KELT-South telescope is located in Sutherland, South Africa and construction started in 2008. The telescope has been operating at full capacity since 2010, after two commissioning seasons from late 2008 to early 2010. I developed all the code that allows it to be fully automatic and robotic and over the last 5 years I have been responsible for the observing operations and general maintenance of the telescope.Town I also developed many other software tools that help with the identification of the exoplanet candidates. The Kilodegree Extremely Little Telescope (KELT) project at present consists of two robotic, wide field, small aperture telescopes that are designed primarily to find transiting exoplanets around bright stars in the magnitude range 8 < V < 11. Transiting planets orbiting bright stars can be studied with intense follow-upCape programs with relative ease on larger telescopes, making them favourable targetsof to determine the atmospheric composition of the planet as well as a host of other properties that cannot be obtained from planets orbiting fainter stars. Of the known 1811 (August 2014) exoplanets only 60 are transiting stars with V < 11 and only 16 of those have been found from the southern hemisphere. The discovery of more of these exoplanets will help constrain the theories of formation and evolution of short period, gas giant exoplanets. Data reduction on one of the commissioning datasets was completed in 2012. The dataset spans 46 days and lightcurves for 78297 objects were obtained. I performed a search for periodicities in theUniversity lightcurves and found that 1411 stars showed clear signs of variability and these objects were compiled into a catalogue of possible variable stars. 1018 of the catalogue members were not previously known to be variable. I searched for planetary transits and eight possible exoplanet candidates were identified. Photometric follow-up observations of two targets eliminated them as exoplanet candidates, each being a blended eclipsing binary system. The remaining six candidates are awaiting follow-up observations at present. Although the commissioning dataset served primarily to refine the data reduction pipeline and the procedures I used to find variable stars, I have demonstrated that the KELT-South telescope is capable of detecting the kinds of signals required for exoplanet discovery. Town Cape of University Acknowledgements I would like to thank the many individuals who assisted me in all aspects of this thesis and those that helped me through the rough times without being directly involved with the work. Firstly, and most importantly, I would like to thank my parents for the love and support throughout my entire life. A special thanks to my Dad who taught me the names of the planets in our Solar System before I could read, which is probably the initial seed that sparked my lifelong fascination with astronomy. To my Mom, thanks for listening to my endless questions, always trying to understand what I was strugglingTown with and encouraging me to find the answers myself when no one else was able to provide them. This thesis is dedicated to both of you. I would like to express my appreciation for all the love and support I received from Stephanie, my soon to be wife. You might not have beenCape part of this thesis from the start, but you were instrumental in its completion. Your words and deeds of encouragement made the last few months much easier and I cannot imagineof how I would have been able to finish this task without you. I am truly blessed to have someone as \ama{zing" as you in my life. I was fortunate to have supervisors that allowed me the freedom to explore my own interests and offered support and guidance whenever I needed it. Patricia and John, you have made the last couple of years much easier by letting me do my own thing, but getting me back on the right path when I strayed too far. A huge thank you has to go to my unofficial supervisor on this project, Josh. Without you the KELT-SouthUniversity project would never have happened and I would never have had the opportunity to work on an amazing project like this. I appreciate all the time and guidance you provided even though I wasn't officially your student to mentor. I would really like to thank Keivan for giving me the opportunity to visit the USA on three occasions and providing all the financial support that enabled those trips. I learned so much about being the best possible scientist from all the people at Vanderbilt and I thank you for all the insightful discussions. To my sister (and your four amazing kids) I would like to extend a special thank you. You've been there from the start and you always believed in your \big brother", you've been a true inspiration to me over these last few years. To all my school friends, although we've not had much time to chat in the last few years, you've been supportive every time we did have a change to meet and I really appreciate the encouragement. A very special mention to all my office mates at SAAO over the last couple of years, thanks for all the encouragement, guidance, sharing of ideas and many unforgettable trips to Sutherland. Cold nights fixing telescopes were much easier knowing that a nice hot coffee (and a laugh) was always available when I needed it. I would never have made it through to the end without you. Thanks to my colleagues (that became life long friends) Marissa, Enrico and Paul, you have been vital in the completion of this thesis and I cannot thank you enough for all the support. To all my friends and colleagues at Vanderbilt University, thanks for making me feel at home the minute I arrived in Nashville for the very first time. Y'all made the second and third trips so much easier knowing that I had friends I could call on. To Joey, thanks for taking over the telescope operations and maintenance duties over the last few months while I concentrated all efforts on typing up this thesis. KELT-South is in good hands and I look forward to working with you in future on all aspects related to KELT-South. Everybody at SAAO should also get a mention, especially Piet, Willie, Gareth, Simon, Nimrod, Chantal, Hamish and Amanda. All of you were willing to help in all aspects of the KELT-South project and provided enormous amounts of advice on telescope hardware, electrical systems, computers, code and so much more. I wouldTown also like to thank the amazing ladies at the Sutherland observing hostel that provided awesome meals three times a day (and sometimes so extras) during my eight month stay in Sutherland during the construction of KELT-South. Thanks to John, Jaci, Hennie, Michael, and all other members of the support staff in Sutherland that were always availableCape with extra hands when one pair just wasn't enough to get things done. With a project such as KELT-South,of there are far more people that I need to thank than there is space in this thesis∗. I appreciate all the help I received and will never forget your contributions that allowed KELT-South to evolve from a pile of bricks to a fully automated machine capable of finding other worlds. ∗This researchUniversity made use of data products from: • The Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Centre/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. • The VizieR catalogue access tool and the SIMBAD database, operated at CDS, Strasbourg, France. • The International Variable Star Index (VSX) database, operated at AAVSO, Cambridge, Mas- sachusetts, USA. • The NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. • The Exoplanet Orbit Database and the Exoplanet Data Explorer at http://www.exoplanets.org. • The Exoplanet Encyclopaedia at http://www.exoplanets.eu. • The Transiting Exoplanet Catalogue at http://www.astro.keele.ac.uk/jkt/tepcat/tepcat.html. Plagiarism Declaration I, Rudolf B. Kuhn, know that plagiarism is wrong. Plagiarism is the use of another person's ideas or published work and to pretend that it is one's own. This therefore amounts to theft. Each significant contribution to, and quotation in this work that I have obtained from other people's published works or unpublished sources has been attributed, and has been cited and fully referenced.