A NEAR-INFRARED STUDY OF THE K3-50 REGION OF HIGH-MASS STAR FORMATION

摘要

In an ongoing study of high-mass star formation regions in the near infrared (1-5 μm), we present J (1.2 μm), H (1.65 μm), K (2.23 μm), and L″ (3.81 μm) broadband images as well as Brγ (n = 7 → 4, 2.166 μm) and Brα (n = 5 → 4, 4.052 μm) hydrogen recombination line images, and 3.29 μm unidentified feature emission images of the K3-50 H Ⅱ regions K3-50A and K3-50B, at a plate scale of ～0.33″ per pixel. The Brackett line images are combined with radio data to map the line-of-sight dust extinction to the compact H Ⅱ region on small spatial scales. The 3.29 μm emission is found to overlap and extend beyond the Brα and Brγ emission into the photodissociation region. We find clumps of dust extinction that may indicate a cluster of stars is in the process of forming. The overall structure of region K3-50A appears to be that of a rotating torus of dense gas with a bipolar ionized gas outflow breaking through to the north and south.