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C. G. De Pree (Agnes Scott College), D. J. Wilner (CfA), W. M. Goss (NRAO), W.J. Welch (UC Berkeley)
Spectral line observations of the W49A North massive star forming region made with the Very Large Array (VLA) have detected H52\alpha (7 mm) radio recombination line (RRL) emission from 15 ultracompact HII regions on 50 milliarcsecond (600 AU) scales. Seven of the sources were unresolved in previous spectroscopic observations of the region. These spectra have been combined with high-resolution continuum imaging of the region at 3.6 cm, 1.3 cm and 7 mm with the VLA and at 3 mm with the Berkeley Illinois Maryland Association (BIMA) array. Four of the newly resolved sources (B2, B3, G2a and G2b) have both broad RRLs (\DeltaV>50 km/s) and rising spectra, with indices (\alpha) ranging from 0.8 to 1.1. We propose, based on line and continuum observations that reveal bipolar and elongated source morphologies, that in a number of sources we may be observing ionized winds that arise from circumstellar disks.