S255-2: The Formation of a Stellar Cluster

摘要

As part of an ongoing study of high-mass star formation regions, we have imaged the S255-2 triple H II region in near-infrared broadband wavelength bands J (1.23 μm), H (1.65 μm), K (2.23 μm), and at 3.3 μm. We have also obtained images in the Brγ and Brα hydrogen recombination lines, in the H_2, v = 1 →0 S(1) line, and in the 3.29 μm dust feature emission band. The region consists of a circular core of stars and young stellar objects, as well as nebulosity, and a more diffuse stellar cluster. The Brackett-line emission from the region is at least a factor of 10 greater than the value estimated from the radio continuum flux density, assuming case B recombination.