NGC 7538 IRS 1 - Subarcsecond resolution recombination line and (N-15)H3 maser observations

Abstract

The present imaging of the NGC 7538 IRS 1-associated (N-15)H3 (J, K) = (3, 3) maser emission with 0.2-arcsec resolution shows the strongest such masers, which may be amplifying the strong double-lobe radio continuum core of the IRS 1 H II region, to be concentrated in two regions separated by about 0.2 arcsec. Observations of several hydrogen recombination line transitions indicate that the velocity of the IRS H II region is similar to that of the ambient molecular cloud.