David Hollenbach

Mid-Infrared IRS Spectroscopy of NGC 7331: A First Look at the SINGS Legacy

Published in The Astrophysical Journal Supplement Series

The nearby spiral galaxy NGC 7331 was spectrally mapped from 5 to 38 μm using all modules of Spitzer's Infrared Spectrograph (IRS). A strong new dust emission feature, presumed due to polycyclic aromatic hydrocarbons, was discovered at 17.1 μm. The feature's intensity is nearly half that of the ubiquitous 11.3 μm band. The 7-14 μm spectral maps rev...

Velocity-resolved far-infrared spectra of forbidden Fe II - Evidence for mixing and clumping in SN 1987A

The forbidden F II profiles at 18 and 26 micron from SN 1987A have been measured with a resolution of about 400 km/s. The central portion of each profile is well-fitted by a Gaussian with a FWHM of 2900 and 2500 km/s, respectively. The centroid velocity is redshifted relative to the LSR by 450 + or - 200 km/s at 18 microns and by 680 + or - 200 km/...