TESTING THE EVOLUTIONARY SEQUENCE OF HIGH-MASS PROTOSTARS WITH CARMA

We present 1 '' resolution Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of the 3 mm continuum and 95 GHz CH(3)OH masers toward 14 candidate high-mass protostellar objects (HMPOs). Dust continuum emission is detected toward seven HMPOs, and CH(3)OH masers toward five sources. The 3 mm continuum sources have diameters <2 x 10(4) AU, masses between 21 and 1200 M(circle dot), and volume densities >10(8) cm(-3). Most of the 3 mm continuum sources are spatially coincident with compact H II regions and/or water masers, and are presumed to be formation sites of massive stars. A strong correlation exists between the presence of 3 mm continuum emission, 22 GHz H(2)O masers, and 95 GHz CH(3)OH masers. However, no 3 mm continuum emission is detected toward ultracompact H II regions lacking maser emission. These results are consistent with the hypothesis that 22 GHz H(2)O masers and CH(3)OH masers are signposts of an early phase in the evolution of an HMPO before an expanding H II region destroys the accretion disk.