Search Publications
The relation between AGN hard X-ray emission and mid-infrared continuum from ISO spectra: Scatter and unification aspects
Lutz, D.; Maiolino, R.; Moorwood, A. F. M. +1 more
We use mid-infrared spectral decomposition to separate the 6 µm mid-infrared AGN continuum from the host emission in the ISO low resolution spectra of 71 active galaxies and compare the results to observed and intrinsic 2-10 keV hard X-ray fluxes from the literature. We find a correlation between mid-infrared luminosity and absorption correc…
ISO spectroscopy of disks around Herbig Ae/Be stars
van den Ancker, M. E.; Acke, B.
We have investigated the infrared spectra of all 46 Herbig Ae/Be stars for which spectroscopic data are available in the ISO data archive. Our quantitative analysis of these spectra focuses on the emission bands at 3.3, 6.2, ``7.7'', 8.6 and 11.2 micron, linked to polycyclic aromatic hydrocarbons (PAHs), the nanodiamond-related features at 3.4 and…
Some empirical estimates of the H2 formation rate in photon-dominated regions
Boulanger, F.; Walmsley, C. M.; Habart, E. +2 more
We combine recent ISO observations of the vibrational ground state lines of H2 towards Photon-Dominated Regions (PDRs) with observations of vibrationally excited states made with ground-based telescopes in order to constrain the formation rate of H2 on grain surfaces under the physiconditions in the layers responsible for H
Mapping ices in protostellar environments on 1000 AU scales. Methanol-rich ice in the envelope of Serpens SMM 4
van Dishoeck, E. F.; Pontoppidan, K. M.; Dartois, E.
We present VLT-ISAAC L-band spectroscopy toward 10 stars in SVS 4, a 30 arcsec×45 arcsec dense cluster of pre-main sequence stars deeply embedded in the Serpens star forming cloud. The ISAAC spectra are combined with archival imaging from UKIRT and ISOCAM to derive accurate extinctions toward the SVS 4 stars. The data are then used to construct a …
Mid-infrared emission of galactic nuclei. TIMMI2 versus ISO observations and models
Siebenmorgen, R.; Krügel, E.; Spoon, H. W. W.
We investigate the mid-infrared radiation of galaxies that are powered by a starburst or by an AGN. For this end, we compare the spectra obtained at different spatial scales in a sample of infrared bright galaxies. ISO observations which include emission of the nucleus as well as most of the host galaxy are compared with TIMMI2 spectra of the nucl…
Warm dust and aromatic bands as quantitative probes of star-formation activity
Förster Schreiber, N. M.; Roussel, H.; Sauvage, M. +1 more
We combine samples of spiral galaxies and starburst systems observed with ISOCAM on board ISO to investigate the reliability of mid-infrared dust emission as a quantitative tracer of star formation activity. The total sample covers very diverse galactic environments and probes a much wider dynamic range in star formation rate density than previous…
Tentative identification of urea and formamide in ISO-SWS infrared spectra of interstellar ices
Duvernay, F.; Chiavassa, T.; Dartois, E. +4 more
Laboratory experiments involving vacuum ultraviolet (VUV) irradiation of solid isocyanic acid (HNCO) at 10 K, followed by infrared spectroscopy (FTIR), are used to interpret the complex spectra associated with Interstellar Medium (ISM) dust grains, particularly the spectra associated with the icy phase observed toward dense molecular clouds. The c…
Dust emission in early-type galaxies: The mid-infrared view
Madden, S. C.; Galliano, F.; Sauvage, M. +2 more
We present mid-infrared (MIR) maps for a sample of 18 early-type galaxies observed at 4.5, 6.7 and 15 µ m with the ISOCAM instrument on board the ISO satellite with a 6'' spatial resolution. We model the Spectral Energy Distribution (SED) of these galaxies using the stellar evolutionary synthesis model PÉGASE and we derive the MIR excess ove…
The young stellar population in the Serpens Cloud Core: An ISOCAM survey
Prusti, T.; Perault, M.; Olofsson, G. +18 more
We present results from an ISOCAM survey in the two broad band filters LW2 (5-8.5 µm) and LW3 (12-18 µm) of a 0.13 square degree coverage of the Serpens Main Cloud Core. A total of 392 sources were detected in the 6.7 µm band and 139 in the 14.3 µm band to a limiting sensitivity of ∼2 mJy. We identified 53 Young Stellar Obj…
ISO observations of the Galactic center interstellar medium. Neutral gas and dust
Rodríguez-Fernández, N. J.; Martín-Pintado, J.; Fuente, A. +1 more
The 500 central pc of the Galaxy (hereafter GC) exhibit a widespread gas component with a kinetic temperature of 100-200 K. The bulk of this gas is not associated to the well-known thermal radio continuum or far infrared sources like Sgr A or Sgr B. How this gas is heated has been a longstanding problem. With the aim of studying the thermal balanc…