FURTHER-STUDIES ON THE CHAMPAGNE PHASE OF GM-24 (IRAS-17136-3617)

We observed with the VLA the H II region associated with the cometary nebula GM 24 at the 3.6 and 6 cm continuum, the H92alpha recombination line, and the water maser line. These observations suggest the presen ce of a ''champagne'' flow of ionized gas. We detected two extended ra dio continuum sources emitting optically thin free-free radiation. The stronger one [S(nu)(total) congruent-to 4 Jy] is associated with GM 2 4, while the weaker one [S(nu)(total) congruent-to 0.1 Jy], located ap proximately 1'5 south of GM 24, is related to an optical nebula in the region. The maximum of radio continuum emission coincides with the so urce IRAS 17136-3617, which is the core of an infrared star cluster. T he spectral line data show two velocity components toward GM 24 separa ted by approximately 10 km s-1. The velocity of the stronger and more compact component is close to the molecular cloud velocity, while its peak of line intensity coincides with the core of the star cluster. Th e largest H92alpha line widths (DELTAV congruent-to 46 km s-1) are als o observed toward this position. The second velocity component (the we aker and extended one) is redshifted by approximately 10 km s-1 with r espect to the velocity of the ambient molecular cloud. We suggest as a possible scenario that this velocity component constitutes emission f rom the ionized gas which is breaking out of the cloud and expanding a way from us. A water maser source, with four velocity compoments, is l ocated approximately 15'' southwest of the peak of the radio continuum emission.