Variable stars in the SuperWASP all sky survey

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The SuperWASP all sky photometric survey (Pollacco et al. 2006) is the most successful ground based search for transiting exoplanets, having discovered more than 150 hot Jupiters. In 10 years of operation, it has also produced an archive of more than 30 million high cadence lightcurves comprising over 500 billion individual measurements of bright stars. In recent years we have exploited this photometric archive to address aspects of stellar evolution, focussing on eclipsing binaries and stellar multiplicity (Lohr et al. 2012; 2013a; 2013b; 2014a; 2014b; 2015a; 2015b) and on stellar pulsations (Norton et al. 2016; Holdsworth et al. 2014; Smalley et al. 2011; 2017). Much of this work was inspired by our initial work on identifying new periodic variable stars coincident with ROSAT X-ray sources (Norton et al. 2007). That initial cross-correlation was performed on only the first few years of SuperWASP data but yielded hundreds of matches for new variable objects.Following a 50 CPU-year run on our linux cluster, we are nearing completion of a new search for periodic variability in the entire SuperWASP archive of 30 million stellar lightcurves. Up to a million objects are detectably periodically variable on timescales from hours to years. An initial aim of this PhD project will be to carry out a similar analysis to that of Norton et al. (2007) but cross-correlating against the full SuperWASP archive and a much larger X-ray catalogue, such as the 2XMMi-DR3 catalogue of almost 300,000 X-ray point sources (Watson et al 2009), so yielding an order of magnitude increase in the resulting catalogue. Following publication of the results from this work, the PhD candidate appointed will explore further aspects of stellar variability, multiplicity, pulsation, and rotation, which may include searches for stellar mergers, pulsating stars in eclipsing binaries, and other rare systems.References:Holdsworth, D.L. et al. 2014, MNRAS, 439, 2078Lohr, M.E., Norton, A.J., Kolb, U.C., et al. 2012, A&A, 542, 124 Lohr, M.E., Norton, A.J., Kolb, U.C., et al. 2013a, A&A, 549, 86 Lohr, M.E., Norton, A.J., Kolb, U.C., Boyd, D., 2013b, A&A, 558, 71Lohr, M.E., Hodgkin, S., Norton, A.J., Kolb, U.C., 2014a, A&A, 563, 34 Lohr, M.E., Norton, A.J., Kolb, U.C., et al., 2014b, A&A, 566, 128Lohr, M.E., Norton, A.J., Kolb, U.C., et al., 2015a, A&A, 578, 103 Lohr, M.E., Norton, A.J., et al., 2015b, A&A, 578, 136Norton, A.J., et al. 2007, A&A, 467, 785Norton, A.J., Lohr, M.E., et al., 2016, A&A, 587, 54Pollacco, D. et al., 2006, PASP, 118, 1407-1418 Smalley, B., et al. 2011, A&A, 535, 3 Smalley, B., et al. 2017, MNRAS, 465, 2662Watson, M.G., et al. 2009, A&A, 493, 339