The Stellar Content of Nearby Star-forming Galaxies (III)
Publication date: 20 Jul 2005
Authors: Chandar, R., et al.
Copyright: 2005. The American Astronomical SocietyWe investigate the nature of the diffuse intracluster ultraviolet light seen in 12 local starburst galaxies, using longslit ultraviolet spectroscopy obtained with the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope (HST ). We take this faint intracluster light to be the field in each galaxy and compare its spectroscopic signature with Starburst99 evolutionary synthesis models and with neighboring star clusters. Our main result is that the diffuse ultraviolet light in 11 of the 12 starbursts lacks the strong O star wind features that are clearly visible in spectra of luminous clusters in the same galaxies. The difference in stellar features dominating cluster and field spectra indicates that the field light comes primarily from a different stellar population and not from scattering of UV photons originating in the massive clusters.