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We present the results of a survey of 45 young (<250 Myr), close (<50 pc)stars with the Simultaneous Differential Imager (SDI) implemented at the VLTand the MMT for the direct detection of extrasolar planets. As part of thesurvey, we observed 54 objects total, of which 45 were close, young stars, 2were somewhat more distant (<150 pc), very young (<10 Myr) stars, 3 were starswith known radial velocity planets, and 4 were older, very nearby (<20 pc)solar analogues. Our SDI devices use a double Wollaston prism and a quad filterto take images simultaneously at 3 wavelengths surrounding the 1.62 um methaneabsorption bandhead found in the spectrum of cool brown dwarfs and gas giantplanets. In our VLT data, we achieved H band contrasts > 10 mag (5 sigma) at aseparation of 0.5" from the primary star on 45% of our targets and H bandcontrasts of > 9 mag at a separation of 0.5'' on 80% of our targets. With thisdegree of attenuation, we should be able to image (5sigma detection) a 5M_{Jup} planet 15 AU from a 70 Myr K1 star at 15 pc or a 5 M_{Jup} planet at 2AU from a 12 Myr M star at 10 pc. We believe that our SDI images are thehighest contrast astronomical images ever made from ground or space for methanerich companions <1'' from their star. For the best 20 of our survey stars, weattained 50% 5 sigma completeness for 6-10 M_Jup planets at semi-major axes of20-40 AU. Thus, our completeness levels are sufficient to significantly testtheoretical planet distributions. From our survey null result, we can rule out(at the 98% confidence/2.0sigma level) a model planet population using a planetdistribution where N(a) $\propto$ constant out to a distance of 45 AU (furthermodel assumptions discussed within).

An Imaging Survey for Extrasolar Planets around 45 Close, Young Stars with SDI at the VLT and MMT