Thermal radio sources in BOK globules

We report VLA-D 6 cm continuum observations of 10 radio sources previously detected at lambda=3.6 cm towards a sample of 7 Bok globules. All sources, with the exception of CB 34 VLA1, were detected at 6 cm. We find that the spectral indices alpha((6-3.6 cm)) of the emission from these objects cover a wide range, from greater than or equal to -3.5 to 1.4. Large negative spectral indices suggesting nonthermal emission were found for the sources CB 205 VLA1, CB 205 VLA3, and CB 230 VLA1, and we cannot conclude that these sources are embedded in the Bok globules CB 205 and CB 230. Spectral indices alpha((6-3.6 cm)) greater than or equal to -0.1 are exhibited by the sources CB 34 VLA1, CB 54 VLA1, CB 108 VLA1, CB 171 VLA1, CB 205 VLA2, CB 230 VLA2, and CB 244 VLA1. Thus, the cm radio continuum emission from these sources is consistent with a thermal origin, indicating that the sources are embedded in the globules. In particular, we propose CB 108 VLA1, CB 171 VLA1, and CB 205 VLA2 to be genuine Class 0 protostar candidates. (C) 1997 American Astronomical Society.