Search Publications
ISM properties in low-metallicity environments
Madden, S. C.; Galliano, F.; Sauvage, M. +1 more
We present new ISOCAM mid-infrared spectra of three starbursting nearby dwarf galaxies, NGC 1569, NGC 1140 and II Zw 40 and the 30 Dor region of the LMC and explore the properties of the ISM in low-metallicity environments, also using additional sources from the literature. We analyse the various components of the ISM probed by the mid-infrared ob…
[Si II], [Fe II], [C II], and H2 Emission from Massive Star-forming Regions
Kaufman, Michael J.; Wolfire, Mark. G.; Hollenbach, David J.
We calculate the [Si II] 34.8 µm, [Fe II] 26.0 µm, and [C II] 158 µm infrared fine-structure emission that may arise from ionized gas (H II regions) and/or associated neutral gas (photodissociation regions [PDRs]) in massive star-forming regions. Assuming thermal pressure balance between an H II region and a PDR, the relative amo…
Pixie Dust: The Silicate Features in the Diffuse Interstellar Medium
Tielens, A. G. G. M.; Chiar, J. E.
We have analyzed the 9.7 and ``18'' µm interstellar silicate absorption features along the line of sight toward four heavily extincted galactic WC-type Wolf-Rayet (WR) stars. We construct two interstellar extinction curves from 1.25 to 25 µm using near-IR extinction measurements from the literature, along with the silicate profiles of …
Nearby Debris Disk Systems with High Fractional Luminosity Reconsidered
Apai, D.; Derekas, A.; Ábrahám, P. +5 more
By searching the IRAS and ISO databases, we compiled a list of 60 debris disks that exhibit the highest fractional luminosity values (fd>10-4) in the vicinity of the Sun (d<120 pc). Eleven out of these 60 systems are new discoveries. Special care was taken to exclude bogus disks from the sample. We computed the fraction…
Mid-Infrared Spectral Diagnostics of Nuclear and Extranuclear Regions in Nearby Galaxies
Helou, G.; Moustakas, J.; Roussel, H. +19 more
Mid-infrared diagnostics are presented for a large portion of the Spitzer Infrared Nearby Galaxies Survey (SINGS) sample plus archival data from ISO and Spitzer. The SINGS data set includes low- and high-resolution spectral maps and broadband imaging in the infrared for over 160 nuclear and extranuclear regions within 75 nearby galaxies spanning a…
Spitzer 70 and 160 µm Observations of the Extragalactic First Look Survey
Im, M.; Frayer, D. T.; Surace, J. A. +33 more
We present 70 and 160 µm observations from the Spitzer extragalactic First Look Survey (xFLS). The data reduction techniques and the methods for producing co-added mosaics and source catalogs are discussed. Currently, 26% of the 70 µm sample and 49% of the 160 µm-selected sources have redshifts. The majority of sources with redsh…
Detection of the 205 µm [N II] Line from the Carina Nebula
Stark, A. A.; Stacey, G. J.; Oberst, T. E. +7 more
We report the first detection of the 205 µm 3P1-->3P0 [N II] line from a ground-based observatory using a direct detection spectrometer. The line was detected from the Carina star formation region using the South Pole Imaging Fabry-Perot Interferometer (SPIFI) on the Antarctic Submillimeter Telescope and R…
Spatial mapping of ices in the Ophiuchus-F core. A direct measurement of CO depletion and the formation of CO_2
Pontoppidan, K. M.
Aims.Ices in dense star-forming cores contain the bulk of volatile molecules apart from H2 and thus represent a large fraction of dark cloud chemistry budget. Mm observations of gas provide indirect evidence for significant freeze-out of CO in the densest cores. To directly constrain the freeze-out profile of CO, the formation route of CO2 and the…
Spitzer/IRAC and ISOCAM/CVF insights on the origin of the near to mid-IR Galactic diffuse emission
Boulanger, F.; Reach, W. T.; Flagey, N. +3 more
Spitzer/IRAC images of extended emission provide a new insight on the nature of small dust particles in the Galactic diffuse interstellar medium. We measure IRAC colors of extended emission in several fields covering a range of Galactic latitudes and longitudes outside of star forming regions. We determine the nature of the Galactic diffuse emissi…
Infrared photometry and evolution of mass-losing AGB stars. I. Carbon stars revisited
Ciprini, S.; Guandalini, R.; Busso, M. +2 more
As part of a reanalysis of galactic Asymptotic Giant Branch (AGB) stars at infrared (IR) wavelengths, we discuss a sample (357) of carbon stars for which mass loss rates, near-IR photometry and distance estimates exist. For 252 sources we collected mid-IR fluxes from the MSX (6C) and the ISO-SWS catalogues. Most stars have spectral energy distribu…