M. J. Ward
Gemini 8m Telescopes Project, 950 N. Cherry Ave., Tucson AZ 85719
Dept. de Physique, Univ. de Montreal, CP 6128, Succ. Centre-ville, Montreal (QC), H3C 3J7, Canada
Dept. of Astrophysics, Univ. of Oxford, Keble Road, Oxford, OX1 3RH, UK
M. J. Ward
Long slit H- and K-band near-infrared spectra have been acquired through the bright nuclear starburst region in the nearby galaxy M83. The spatial distribution of the stellar CO 2-0 absorption band broadly resembles that of the 2µm continuum emission and has a maximum depth consistent with a pure starburst population. The band strength deceases monotonically away from this location to a value consistent with that seen in the giant-dominated populations in ellipticals and the bulges of spiral galaxies. There is no significant variation in the ratio of H (CO 6-3) and K (CO 2-0) band equivalent widths which argues against any significant dilution of the bands by hot dust. The CO depth and Br emission line equivalent width are anti-correlated. Comparison with starburst evolutionary models indicates an age gradient across this central region.
Submitted to the Astrophysical Journal.
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