2010ApJ...715..671W

We report on a multiwavelength study of a partially embedded region of star formation centered on the Herbig Be star LkHα 101. Using two 40 ks Chandra observations, we detect 213 X-ray sources in the17' x17' ACIS-I field. We combine the X-ray data with Two Micron All Sky Survey near-IR observations and Spitzer IRAC and MIPS 24 µm observations to obtain a complete picture of the cluster. A total of 158 of the X-ray sources have infrared counterparts. Of these, we find nine protostars, 48 Class II objects, five transition objects, and 72 Class III objects. From the Spitzer data we identify an additional 10 protostars, 53 Class II objects, and four transition disk candidates which are not detected by Chandra. We obtained optical spectra of a sample of both X-ray-detected and non-X-ray-detected objects. Combining the X-ray, Spitzer, and spectral data, we obtain independent estimates of cluster distance and the total cluster size–excluding protostars. We obtain consistent distance estimates of 510⁺¹⁰⁰_–40 pc and a total cluster size of 255⁺⁵⁰_–25stars. We find the Class II:III ratio is about 5:7 with some evidence that the Class III sources are spatially more dispersed. The cluster appears very young with three sites of active star formation and a median age of about 1 Myr.