The Collinder 69 cluster in the context of the Lambda Orionis SFR
  The Lambda Orionis Star Forming Region is a complex structure which includes the Col 69 (Lambda Orionis) cluster and the B30 & B35 dark clouds. We have collected deep optical photometry and spectroscopy in the central cluster of the SFR (Col 69), and combined with 2MASS IR data, in order to derive the Initial Mass Function of the cluster, in the range 50-0.02 M(sun). In addition, we have studied the H(alpha) and lithium equivalent widths, and the optical-infrared photometry, to derive an age (5+-2 Myr) for Col 69, and to compare these properties to those of B30 & B35 members. 
David Barrado y Navascues (1), J.R. Stauffer (2), J. Bouvier (3), R.   Jayawardhana (4) ((1) Laboratorio de Astrofisica Espa...