Program: GN-2010B-Q-1

We propose to use NGS AO Altair/NIRI imaging at Gemini-North to carry out second epoch observations of a carefully selected sample of 25 nearby spectroscopic binaries to confirm if the faint companions discovered in 09B are physical companions. Recent star formation simulations and observations have demonstrated that main sequence spectroscopic binaries have an enhanced wide ($>$30 AU) companion rate compared to single stars. This rate has been found to be from 60\% to nearly 100\% depending on the period of the spectroscopic binary. We will take advantage of this high tertiary companion rate to look for ultracool companions with separations from a few AU ($>$0.1") to a few hundred AU ($<$20"). This is a continuation of a 2009A/B and 2010A program that has been extremely successful. To date, we have high-quality, reduced, first epoch data all of our 91 targets, along with 32 of our 53 2010A second epoch targets. There are six candidates from our second epoch observations that display CPM and warrant further observations. Our sample represents the largest AO survey of spectroscopic binaries. In order to make any use of the remaining first epoch data, we require the second epoch imaging of 25 of these stars observable in 10B and requested in this proposal. This project has proven to be an excellent "poor" sky condition project for Gemini to execute in non-photometric conditions, that will inform our models of star formation and likely detect new nearby ultra-cool faint companions.