Spatially Resolving Substructures within the Massive Envelope around an Intermediate-mass Protostar: MMS 6/OMC-3

摘要: With the Submillimeter Array, brightest (sub)millimeter continuum source in OMC-2/3 region, MMS 6, has been observed 850 um emission with approximately 10 times better angular resolution than previous studies (~0.3"; ~120 AU at Orion). The deconvolved size, mass, and column density of 6-main are estimated to be 0.32"x0.29" (132 AUx120 AU), 0.29 Mo, 2.1x10^{25} cm^{-2}, respectively. extremely high mean number density, 1.5x10^{10} cm^{-3}, suggests that is likely optically thick um. We compare our observational data three theoretical core models: prestellar core, protostellar + disk-like structure, first adiabatic core. These comparisons clearly show cannot modeled as a simple gas temperature 20 K. A self-luminous necessary explain flux wavelengths. Our recent detection very compact energetic outflow CO (3-2) HCN (4-3) lines, supports presence protostar. suggest 6 one cases an intermediate mass young stage. In addition peak, we have also spatially resolved spiky structures sub-clumps, distributed over central 1000 AU. masses these sub-clumps 0.066-0.073 which on order brown dwarf masses. Higher higher sensitivity observations ALMA EVLA will reveal origin nature such whether they originated from fragmentations, spiral arms, or inhomogeneity within structures/envelope.