GravityCam - A novel high-speed and wide-field instrument for a large astronomical telescope, detecting exoplanets and dark matter.

GravityCam is a new high-speed optical instrument proposed for the 3.6 New Technology Telescope at the La Silla Observatory in Chile. The instrument will capable of delivering significantly sharper images from the ground than is normally possible without adaptive optics. Advances in optical and near infrared imaging technologies allow images to be acquired at high speed without significant noise penalty. Aligning these images before they are combined can yield a 3-5 fold improvement in image resolution. By using arrays of such detectors, survey fields may be as wide as the telescope optics allows. GravityCam will be able to greatly accelerate the rate of detection of Earth size planets by gravitational microlensing and will substantially improve the quality of weak shear studies of dark matter distribution in distant clusters of galaxies. An extensive microlensing survey will also provide a vast dataset for asteroseismology studies, and GravityCam promises to generate a unique data set on the population of the Kuiper belt and possibly the Oort cloud.

At the moment two competing night vision technologies are proposed as detectors for GravityCam; Electron Multiplying CCDs (EMCCDs) or CMOS devices. While EMCCDs has been used for high-precision astronomy for a number of years and is a well tested technology, CMOS devices are only approaching a level good enough for astronomy, and more research into their performance is therefore needed.