Large Scale Structure and Kinematics of the Orion Ridge

Abstract

Clumps and filamentary structures have previously been observed in the extended molecular ridge of OMC-1 (see below). The region is affected by multiple outflow components, shock emission that extends 0.5 pc from the BN/KL core, and a foreground HII region expanding into the cloud. The region also displays a complex kinematical character, with a large scale shift in radial velocity along the ridge, multiple cloud velocity components (Womack et al. 1993), and fast gradients across constituent cores (Harris et al. 1983, Wiseman and Ho 1993).To clarify the structure and kinematics of the region, we have used the VLA to observe with high (0.3 km s−1) velocity resolution and high (8”) angular resolution the NH3 (1,1) and (2,2) rotation-inversion lines over 20 adjacent fields covering a 3’ by 8’ region encompassing the KL region.