Dr. Arlin Crotts, at Columbia University, will use this award to complete the analysis of the "MEGA" gravitational microlensing survey of stars in M31. The PI's group has constructed the major hardware for the project, nearly completed observations totaling roughly 350 nights, developed software, and begun the analysis of the data. To-date, a number of likely microlensing events have been found, and the group has developed techniques to distinguish variable stars from microlensing events.
Broader impact of this work to the astronomical research community will result from the existence of data on variable stars that are the byproduct of the microlensing survey. Additionally, the PI will make the image subtraction package, used in the data analysis, available for general distribution. A potential medical application of the analysis technique in producing more sensitive CT-scan detections of small tumors has also been identified, giving this work a multidisciplinary impact.