We present the results from arcsecond resolution observations of various line transitions at 1.3 mm toward hypercompact HII region G28.20-0.04N. With the SMA data, we have detected and mapped the transitions in the CH$_{ 3}$CN, CO, $^{ 13}$CO, SO$_{ 2}$, OCS, and CH$_{ 3}$OH molecular lines as well as the radio recombination line H30$\alpha$. The observations and analysis indicate a hot core associated with G28.20-0.04N. The outflow and possible rotation are detected in this region.
Categories: astro-ph