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Article
Studying the Temperature and Ionization State of the Warm Ionized Medium
217th American Astronomical Society Meeting (2011)
  • Melissa Halford, Cornell University
  • E. J. Mierkiewicz, University of Wisconsin - Madison
  • R. J. Reynolds, University of Wisconsin - Madison
  • G. J. Madsen, University of Sydney, Australia
  • L. M. Haffner, University of Wisconsin - Madison
  • K. A. Barger, University of Wisconsin - Madison
  • F. L. Roesler, University of Wisconsin - Madison
Abstract
Using data from the Wisconsin Hydrogen Alpha Mapper (WHAM) and Pine Bluff Observatory's Spatial Heterodyne Spectrometer (SHS), we studied the warm ionized component of the Galaxy's interstellar medium (WIM). Line ratios of H-alpha, [N II], [O II] and [S II] emission were used to study the WIM gas in both the local spiral arm and more distant areas of the Galaxy. The strength of the [S II] line was used to measure the ionization state in a set of nine look directions and ratios of [N II]/H-alpha and [O II]/H-alpha provide a measure of temperature. Our study expands upon and confirms the results of previous [O II] studies of the WIM, which limited themselves to line ratios including only the local component of the [O II] emission. The work presented here includes a detailed component analysis of WIM emission from non-local gas in the kinematically distinct Perseus spiral arm and uses [S II] data that was not available in the previous [O II] study.
Keywords
  • Interstellar medium,
  • Milky Way
Publication Date
January, 2011
Publisher Statement
Abstract #id.251.09. Also publishing in the Bulletin of the American Astronomical Society, vol. 43, 2011.
Citation Information
Melissa Halford, E. J. Mierkiewicz, R. J. Reynolds, G. J. Madsen, et al.. "Studying the Temperature and Ionization State of the Warm Ionized Medium" 217th American Astronomical Society Meeting (2011)
Available at: http://works.bepress.com/l-m-haffner/12/