PI: Brent Buckalew, Caltech, email@example.com
Address: IPAC, 770 S. Wilson Ave. \\ MS 100-22, Pasadena, CA 91125, USA
Title: Optical Spectroscopy of the SINGS Low Metallicity Extranuclear Target NGC 6822 Hubble I
Abstract: We request two nights on the KPNO 2.1m telescope to undertake CCD spectroscopy of Hubble I, a low-metallicity H \sc ii region in NGC 6822. We request these new spectra to cover the beam resolution of the \it Spitzer Infrared Spectrograph (IRS). Optical spectra are vital to determine the stellar and nebular properties of this H \sc ii region and to interpret the nebular emission lines in our mid-infrared \it Spitzer spectra. Note that these proposed spectra are a part of an optical survey of 22 SINGS extranuclear targets. This larger survey is trying to understand the interplay between young stars, dust, and gas as a function of metallicity and/or age of the star cluster. The importance of understanding the influence of massive stars on their interstellar medium is important to both local and galactic (intergalactic) evolution. The following are a few (though not all) specific scientific studies that are made possible with these optical spectra. We will determine correlations between the extinctions derived in the optical (e.g., H(alpha)/H(beta)) with the dust/PAH properties derived in the mid-infrared spectra. We will compare the ionization ratios based on extincted optical ratios (e.g., [O \sc ii]/[O \sc iii]) to those from the mid-infrared (e.g., [Ne \sc ii]/[Ne \sc iii]) to determine if embedded star formation is present.
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