High-Arctic prototypes

The AWCams (Arctic Wide-field Cameras) are two small telescopes designed to search for exoplanet transits around bright stars (V=5-10). The telescopes, with large CCDs behind camera lenses, are essentially identical to individual Evryscope cameras.  In early 2012 we (in collaboration with the Ray Carlberg @ University of Toronto and Canada’s NRC; see Law et al. 2012, 2013) deployed the telescopes to the PEARL atmospheric science laboratory at 80 degrees N in the Canadian High Arctic, where continuous darkness in winter gives a greatly improved transit detection efficiency.

Like the Evryscope telescopes, the AWCams (Arctic Wide-field Cameras) are based on DSLR (85mm and 50mm focal length) and low-cost front-illuminated CCDs (the 16MPix Kodak KAF16803). The two cameras stare at 500-1000 square degrees around the North Celestial Pole, taking short 10-second exposures to avoid the need to track. The PEARL laboratory is currently unoccupied during the winter months and the AWCams must operate in -40C temperatures and survive Arctic winter storms, which can produce several feet of snow and 100+ mph winds.

We have now operated the AWCams for three winters, including a test run in February 2012 and full-winter operations in the 2012/13 and 2013/14 winters. The robustness of our hardware and enclosure design has been validated by perfect operation throughout the entire deployment period, including a total of 10 months of completely unattended robotic operation. Throughout the winter the cameras kept themselves (and crucially their windows) clear of snow and ice, took over 40TB of images, and consistently maintained few-millimagnitude photometric precisions. The AWCams photometric performance demonstrates that we can routinely achieve precision photometry with the Evryscope telescopes. The AWCam pipeline achieves scintillation-limited photometric precision in each exposure, and binning brings the photometric precision to the 3-millimagnitude level in 10 minutes.