Search Publications
Extragalactic optical-infrared background radiation, its time evolution and the cosmic photon-photon opacity
Rodighiero, G.; Franceschini, A.; Vaccari, M.
Context: The background radiation in the optical and the infrared cause energy loss in the propagation of high energy particles through space. In particular, TeV observations with Cherenkov telescopes of extragalactic sources are influenced by the opacity effects due to the interaction of the very high-energy source photons with the background lig…
The c2d Spitzer Spectroscopic Survey of Ices around Low-Mass Young Stellar Objects. I. H2O and the 5-8 µm Bands
Augereau, J. -C.; Stapelfeldt, K. R.; van Dishoeck, E. F. +23 more
To study the physical and chemical evolution of ices in solar-mass systems, a spectral survey is conducted of a sample of 41 low-luminosity YSOs (L ~ 0.1-10 L⊙) using 3-38 µm Spitzer and ground-based spectra. The sample is complemented with previously published Spitzer spectra of background stars and with ISO spectra of well-studi…
Variations of the Mid-IR Aromatic Features inside and among Galaxies
Madden, Suzanne C.; Jones, Anthony P.; Galliano, Frédéric +2 more
We present the results of a systematic study of mid-IR spectra of Galactic regions, Magellanic H II regions, and galaxies of various types (dwarf, spiral, starburst), observed by the satellites ISO and Spitzer. We study the relative variations of the 6.2, 7.7, 8.6, and 11.3 µm features inside spatially resolved objects (such as M82, M51, 30 …
A Compendium of Far-Infrared Line and Continuum Emission for 227 Galaxies Observed by the Infrared Space Observatory
Dale, Daniel A.; Helou, George; Brauher, James R.
Far-infrared line and continuum fluxes are presented for a sample of 227 galaxies observed with the Long Wavelength Spectrometer on the Infrared Space Observatory. The galaxy sample includes normal star-forming systems, starbursts, and active galactic nuclei covering a wide range of colors and morphologies. The data set spans some 1300 line fluxes…
Centimetre-wave continuum radiation from the ρ Ophiuchi molecular cloud
Paladini, Roberta; Lim, Tanya; Casassus, Simon +8 more
The ρ Oph molecular cloud is undergoing intermediate-mass star formation. Ultraviolet radiation from its hottest young stars heats and dissociates exposed layers, but does not ionize hydrogen. Only faint radiation from the Rayleigh-Jeans tail of ~10-100 K dust is expected at wavelengths longwards of ~3 mm. Yet cosmic background imager (CBI) observ…
Circumstellar water vapour in M-type AGB stars: radiative transfer models, abundances, and predictions for HIFI
Olofsson, H.; Schöier, F. L.; Bergman, P. +2 more
Context: Surprisingly high amounts of H2O have recently been reported in the circumstellar envelope around the M-type asymptotic giant branch star W Hya. This has lead to the speculation that evaporation of icy cometary or planetary bodies might be an effective ongoing mechanism in such systems. However, substantial uncertainties remain, as the re…
High-Ionization Mid-Infrared Lines as Black Hole Mass and Bolometric Luminosity Indicators in Active Galactic Nuclei
Lutz, D.; Sturm, E.; Helou, G. +6 more
We present relations of the black hole mass and the optical luminosity with the velocity dispersion and the luminosity of the [Ne V] and the [O IV] high-ionization lines in the mid-infrared (MIR) for 28 reverberation-mapped active galactic nuclei. We used high-resolution Spitzer Infrared Spectrograph and Infrared Space Observatory Short Wavelength…
Spatially resolved dusty torus toward the red supergiant WOH G64 in the Large Magellanic Cloud
Weigelt, G.; Hofmann, K. -H.; Driebe, T. +2 more
Aims: We present N-band spectro-interferometric observations of the red supergiant
Dust processing in photodissociation regions. Mid-IR emission modelling
Abergel, A.; Habart, E.; Compiègne, M. +1 more
Context: Mid-infrared spectroscopy of dense illuminated ridges (or photodissociation regions, PDRs) suggests dust evolution. Such evolution must be reflected in the gas physical properties through processes like photo-electric heating or H2 formation.
Aims: With Spitzer Infrared Spectrograph (IRS) and ISOCAM data, we study the mid-IR emission …
SWAS Observations of Water in Molecular Outflows
Bergin, Edwin A.; Neufeld, David A.; Kaufman, Michael J. +4 more
We present detections of the ground-state 110→ 101 transition of ortho-H2O at 557 GHz in 18 molecular outflows based on data from the Submillimeter Wave Astronomy Satellite (SWAS). These results are combined with ground-based observations of the J = 1-0 transitions of 12CO and 13CO obtained at…