FIRST SCIENCE OBSERVATIONS WITH SOFIA/FORCAST: PROPERTIES OF INTERMEDIATE-LUMINOSITY PROTOSTARS AND CIRCUMSTELLAR DISKS IN OMC-2

摘要

We examine eight young stellar objects in the OMC-2 star-forming region based on observations from the SOFIA/FORCAST early science phase,the Spitzer Space Telescope,the Herschel Space Observatory,Two Micron All Sky Survey,Atacama Pathfinder Experiment,and other results in the literature.We show the spectral energy distributions (SED) of these objects from near-infrared to millimeter wavelengths,and compare the SEDs with those of sheet collapse models of protostars and circumstellar disks.Four of the objects can be modeled as protostars with infalling envelopes,two as young stars surrounded by disks,and the remaining two objects have double-peaked SEDs.We model the double-peaked sources as binaries containing a young star with a disk and a protostar.The six most luminous sources are found in a dense group within a 0.15×0.25 pc region;these sources have luminosities ranging from 300 L_⊙ to 20 L_⊙.The most embedded source (OMC-2 FIR 4) can be fit by a class 0 protostar model having a luminosity of ～50 L_⊙ and mass infall rate of ～10~(-4) M_⊙ yr~(-1) .