Mid-Infrared Emission Features in Normal, Star-Forming Galaxies

Session 75 - Dust & PAHs in Galaxies.
Display session, Friday, January 09
Exhibit Hall,

[75.06] Mid-Infrared Emission Features in Normal, Star-Forming Galaxies

N. Y. Lu, G. Helou, C. Beichman (IPAC/Caltech), H. L. Dinerstein (U. Texas), D. J. Hollenbach (NASA/Ames), D. A. Hunter (Lowell Obs.), K. Y. Lo (U. Illinois), S. Lord, S. Malhotra (IPAC/Caltech), R. H. Rubin (NASA/Ames), N. Silbermann (IPAC/Caltech), G. Stacey (Cornell U.), H. A. Thronson Jr. (NASA HQ/U. Wyoming), M. W. Werner (JPL/Caltech)

We have been using the PHT-S spectrometer on board the Infrared Space Observatory (ISO) to obtain spectra from 2.5 to 5\,\mum and from 6 to 12\,\mum on a broad sample of about 50 star-forming galaxies. The majority of the spectra we have obtained so far are dominated by broad emission features centered, respectively, around 6.2, 7.7, 8.6 and 11.3\,\mum. It is widely believed that these features are associated with the so-called Polycyclic Aromatic Hydrocarbon (PAH) molecules. We will characterize spectral properties of these emission features; analyze feature-to-feature and features-to-dust continuum emission correlations; and discuss, within the framework of PAHs, some observational implications on the global physical conditions of the carriers of these emission features in normal, star-forming galaxies.

ISO is an ESA mission with participation by NASA and ESA. The PHT (ISO Photometer) was built by Lemke et al. (1996, Aamp;A, 315, L64)

The author(s) of this abstract have provided an email address for comments about the abstract: lu@ipac.caltech.edu

Program listing for Friday