We present the initial results of a new Evryscope white dwarf (WD) survey; we utilize longer baseline observations and a unique periodicity detection algorithm to analyze more targets at dimmer magnitudes than previously achieved by the first Evryscope WD survey. The Evryscopes are all-sky high-cadence telescope arrays operating in the Northern and Southern hemispheres, at Mount Laguna, California and Cerro Tololo, Chile. The Evryscope database contains two-minute cadence observations for 30 million stars, with each light curve containing tens of thousands of epochs. The initial Evryscope WD survey illuminated the challenges of recovering a transiting event around a WD (which would last on the order of minutes due to its compact size) even provided high cadence observations. The original survey analyzed bright targets (mag < 15 in sloan-g') and found zero transiting events. Recovery modeling suggests that the solution to this problem is to go deeper, searching more targets for variability. To achieve this we develop a new periodicity detection algorithm, phased binned coadding. We test this new technique on new Evryscope light curves, which contain an additional year of high cadence observations compared to the previous survey, and present the preliminary results here.
American Astronomical Society Meeting Abstracts #236
- Pub Date:
- June 2020