Introduction \[sec\_introduction\]
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Identifying stellar members associated with a star-forming region is important for studies of the stellar initial mass function (IMF), cluster dynamics, and star formation processes. Stars with dusty protoplanetary disks are readily found in infrared (IR) surveys where disk emission is strong, but when the disks have dissipated, the stars are most easily identified by their strong X-ray flaring. High spatial resolution X-ray observations of an active star forming region with the $Chandra$ X-ray Observatory will often reveal hundreds or thousands of pre-main sequence (PMS) stars, as well as OB stars [@Feigelson07].

An important challenge for membership studies is to distinguish young stars formed in a molecular cloud from various types of contaminant sources along the line-of-sight. In X-ray surveys of star-forming regions, stellar X-ray contaminants include main-sequence (MS) stars [e.g. @Schmitt95; @Schmitt97] and some types of giants [e.g. @Pizzolato00; @Gondoin05]. These foreground and background stellar contaminants have much less impact on surveys in X-ray images than IR images because magnetic activity in PMS stars is elevated $10^{1}-10^{4}$ above levels in older stars [e.g. @Preibisch05]. For star forming regions located in the quadrant of the Galactic plane centered on the Galactic Center, contamination by cataclysmic variables should 