August 11-15, 2014


The search for Transits around White Dwarfs

Ian Braker (University of Leicester)

Ian Braker1, Matt Burleigh1, Katherine Lawrie1, Francesca Faedi2, Mike Goad1, Richard West2
1Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK
2University of Warwick, Department of Physics, Gibbet Hill Road, Coventry CV4 7AL, UK

To date no exoplanets have been observed transiting White Dwarfs. However there is growing evidence that disrupted planetary systems exist around White Dwarfs as both metal rich gas discs and dust discs have been detected in close circumstellar orbits; additionally significant numbers of White Dwarfs show evidence of metal contamination in their photosphere that cannot be explained through radiative pressure or accretion of material from the interstellar medium (ISM) alone. A previous survey using SuperWASP, which monitored a few hundred White Dwarfs, has yet to detect any transiting objects. We review the constraints on the frequency of planets in close in orbits to White Dwarfs from this survey. Additionally we discuss two new surveys, the Next Generation Transit Survey (NGTS) and the Kepler 2 mission and their potential to further constrain the presence of planets around White Dwarfs. Due to the greater precision of these surveys they should be able to detect Earth sized or larger companions within the habitable zone. Finally we discuss the opportunities to monitor brighter White Dwarfs using small, less than 1m, sized telescopes to detect short period (2 - 3 minutes) deep transits of White Dwarfs.

Mode of presentation: poster