Very large array detection of the ionized stellar winds arising from massive stars in the Galactic center arches cluster

The Galactic center Arches stellar cluster, detected and studied until now only in the near-infrared, is comprised of at least 100 massive (M-star greater than or equal to 20 M.) stars. Here we report the detection at centimeter wavelengths of radio continuum emission from eight radio sources associated with the cluster. Seven of these radio sources have rising spectral indices between 4.9 and 8.5 GHz and coincide spatially with the brightest stars in the cluster, as determined from JHK photometry and Br alpha and Br gamma spectroscopy. Our results confirm the presence of powerful ionized winds in these stars. The eighth radio source has a nonthermal spectrum, and its nature is yet unclear, but it could be associated with a lower mass young star in the cluster.