MEDI: An instrument for direct detection of massive extrasolar planets

We have developed an instrument, MEDI (Massive Exoplanet Differential Imager), that takes advantage of a novel method of starlight rejection, simultaneous differential imaging, in order to image massive planets around nearby stars. Using this technique we expect to achieve suppression of starlight to the photon-noise limit, which means that increased exposure time will translate into higher sensitivities. This is in contrast to past sequential and two-color simultaneous studies that reach a sensitivity floor due to speckle-noise limitations. Based on lab results, we expect to be able to detect objects 10(6) times fainter than their primaries in the H band at 0.5" separations in 2 hours. This suggests that we will be sensitive to objects with masses as small as similar to 5M(Jupiter) at separations of greater than similar to 5 AU for G2 V stars that are similar to 300 Myr old and within about 10 pc.