Turner, Oliver David (2017) Discovery and characterisation of transiting extra-solar planets with the Wide Angle Search for Planets (WASP) survey. Doctoral thesis, Keele University.

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In July of 2012 the WASP-South instrument was modified to allow it to collect data on brighter stars. This change was motivated by the dearth of planets known to orbit bright hosts in the southern hemisphere and the depth of study possible for HD209458 b and HD189733 b. These two planets orbit very bright stars in the northern hemisphere and have lead to a wealth of discoveries thanks to the relative ease with which they can be studied.
My initial work with the Wide Angle Search for Planets (WASP) project was to contribute to updating the existing automated data reduction pipeline. I investigated the effects of, and helped to implement, various changes made to the pipeline in order to optimise its performance for brighter stars. During these investigations I also contributed fixes for several pipeline bugs. As a result of these changes the pipeline provides a level of precision with the new data as the previous version did with data from the unmodified instrument.
The modified instrument was initially intended to collect data for 3 years. I performed an investigation in order to see if there was value to be gained in extending this period. I injected simplified transit signals into data gathered with the modified instrument that showed no known or candidate signals. These transit signals had a variety of different periods and depths, ranging from those we would expect to detect to those we would expect to be below our detection limits. My results showed that we can expect to recover between 42% and 72% of hot-Jupiters with transit depths between 0.5% and 2% and periods shorter than 10 days. This is comparable to a similar study of WASP-South before the modifications.
I have also contributed to the follow-up of several newly discovered and previously known planets. I have presented the tools used by WASP to discover and characterise exoplanetary systems and have applied them to the investigation of these systems. With new data, I update and refine parameters for 7 previously known WASP planets. I
resolve discrepancies in previous studies of WASP-31, show that WASP-42 may be an important probe of planet migration theory and show that seemingly “typical” systems may warrant re-observing. I present three newly discovered systems: WASP-120 b, a system with a star showing variable activity and a possibly eccentric planet orbit, WASP-122 b, which offers a good opportunity for atmospheric study, and WASP 123 b, which orbits an old star, ∼ 7 Gyr.

Item Type: Thesis (Doctoral)
Subjects: Q Science > QC Physics
Divisions: Faculty of Natural Sciences > School of Chemical and Physical Sciences
Contributors: Maxted, PFL (Thesis advisor)
Hellier, C (Thesis advisor)
Depositing User: Lisa Bailey
Date Deposited: 07 Jun 2017 11:50
Last Modified: 02 Dec 2020 12:50
URI: https://eprints.keele.ac.uk/id/eprint/3563

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