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We present a study of elemental abundances in a sample of thirteen Blue Compact Dwarf (BCD) galaxies, using the $sim$10--37$mu$m high resolution spectra obtained with Spitzer/IRS. We derive the abundances of neon and sulfur for our sample using the infrared fine-structure lines probing regions which may be obscured by dust in the optical and compare our results with similar infrared studies of starburst galaxies from ISO. We find a good correlation between the neon and sulfur abundances, though sulfur is under-abundant relative to neon with respect to the solar value. A comparison of the elemental abundances (neon, sulfur) measured from the infrared data with those derived from the optical (neon, sulfur, oxygen) studies reveals a good overall agreement for sulfur, while the infrared derived neon abundances are slightly higher than the optical values. This indicates that either the metallicities of dust enshrouded regions in BCDs are similar to the optically accessible regions, or that if they are different they do not contribute substantially to the total infrared emission of the host galaxy.
We present an analysis of the mid-infrared emission lines for a sample of 12 low metallicity Blue Compact Dwarf (BCD) galaxies based on high resolution observations obtained with Infrared Spectrograph on board the {rm Spitzer} Space Telescope. We com
We present 5-38um mid-infrared spectra at a spectral resolution of R~65-130 of a large sample of 22 starburst nuclei taken with the Infrared Spectrograph IRS on board the Spitzer Space Telescope. The spectra show a vast range in starburst SEDs. The s
Based on the ISO spectral catalogue of compact HII regions by Peeters et al. (2001), we present a first analysis of the hydrogen recombination and atomic fine-structure lines originated in the ionized gas. The sample consists of 34 HII regions locate
We performed an analysis of the mid-infared properties of the 12micron Seyfert sample, a complete unbiased 12micron flux limited sample of local Seyfert galaxies selected from the IRAS Faint Source Catalog, based on low resolution spectra obtained wi
IR excesses of white dwarfs (WDs) can be used to diagnose the presence of low-mass companions, planets, and circumstellar dust. Using different combinations of wavelengths and WD temperatures, circumstellar dust at different radial distances can be s