NASA ExoPAG Study Analysis Group 11: Preparing for the WFIRST   Microlensing Survey
  NASA's proposed WFIRST-AFTA mission will discover thousands of exoplanets with separations from the habitable zone out to unbound planets, using the technique of gravitational microlensing. The Study Analysis Group 11 of the NASA Exoplanet Program Analysis Group was convened to explore scientific programs that can be undertaken now, and in the years leading up to WFIRST's launch, in order to maximize the mission's scientific return and to reduce technical and scientific risk. This report presents those findings, which include suggested precursor Hubble Space Telescope observations, a ground-based, NIR microlensing survey, and other programs to develop and deepen community scientific expertise prior to the mission. 
Jennifer C. Yee, Michael Albrow, Richard K. Barry, David Bennett,   Geoff Bryden, Sun-Ju Chung, B. Scott Gaudi, Neil Gehrels...
astro-ph.EP