Search Publications
The spectrum of comet Hale-Bopp (C/1995 O1) observed with the infrared space observatory at 2.9 astronomical units from the sun.
Altieri, B.; Keller, H. U.; Lellouch, E. +5 more
Observations of the Hubble Deep Field with the Infrared Space Observatory - V. Spectral energy distributions, starburst models and star formation history
Elbaz, D.; Danese, L.; Franceschini, A. +16 more
We have modelled the spectral energy distributions of the 13 Hubble Deep Field (HDF) galaxies reliably detected by the Infrared Space Observatory (ISO). For two galaxies the emission detected by ISO is consistent with being starlight or the infrared `cirrus' in the galaxies. For the remaining 11 galaxies there is a clear mid-infrared excess, which…
Infrared Space Observatory Measurements of [C II] Line Variations in Galaxies
Helou, G.; Stacey, G.; Malhotra, S. +11 more
We report measurements of the [C II] fine-structure line at 157.714 µm in 30 normal star-forming galaxies with the Long Wavelength Spectrometer (LWS) on the Infrared Space Observatory (ISO). The ratio of the line to total far-infrared (FIR) luminosity, L[CII]/LFIR, measures the ratio of the cooling of gas to that of dus…
Infrared spectroscopy of interstellar apolar ice analogs
van Dishoeck, E. F.; Tielens, A. G. G. M.; Boogert, A. C. A. +2 more
Apolar ices have been observed in several regions in dense clouds and are likely dominated by molecules such as CO, CO_2 and the infrared inactive molecules O_2 and N_2. Interstellar solid CO has been well characterized by ground-based high resolution measurements. Recent ISO results showed the ubiquitous presence of abundant CO_2 ice and the pres…
External supply of oxygen to the atmospheres of the giant planets
Lellouch, E.; Encrenaz, T.; de Graauw, T. +3 more
The atmospheres of the giant planets are reducing, being mainly composed of hydrogen, helium and methane. But the rings and icy satellites that surround these planets, together with the flux of interplanetary dust, could act as important sources of oxygen, which would be delivered to the atmospheres mainly in the form of water ice or silicate dust…
Infrared Spectroscopy of Dust in the Diffuse Interstellar Medium toward Cygnus OB2 No. 12
de Graauw, Th.; Prusti, T.; van Dishoeck, E. F. +7 more
Observations made with the short-wavelength spectrometer of the Infrared Space Observatory are used to investigate the composition of interstellar dust in the line of sight to Cygnus OB2 No. 12, commonly taken as representative of the diffuse (low-density) interstellar medium. Results are compared with data for the Galactic center source Sgr A*. N…
Warm molecular envelope of M giants and Miras: a new molecule forming region unmasked by the ISO SWS.
Ohnaka, K.; Yamamura, I.; Tsuji, T. +1 more
Our observations with the ISO SWS revealed that H_2_O band at 2.7µm appears as absorption already in an M2 giant β Peg and strengthens towards later M giants. Further, CO_2_ 4.2µm band appears as absorption in an M7 giant SW Vir and especially strong in a Mira variable S Vir. The excitation temperatures of these molecular bands estimat…
Discovery of Interstellar Hydrogen Fluoride 1
Neufeld, David A.; Phillips, Thomas G.; Schilke, Peter +1 more
We report the first detection of interstellar hydrogen fluoride. Using the Long Wavelength Spectrometer of the Infrared Space Observatory (ISO), we have detected the 121.6973 µm J=2-1 line of HF in absorption toward the far-infrared continuum source Sagittarius B2. The detection is statistically significant at the 13 σ level. On the basis of…
First results of ISO-SWS observations of Saturn: detection of CO_2_, CH_3_C_2_H, C_4_H_2_ and tropospheric H_2_O.
Beintema, D. A.; Lellouch, E.; Encrenaz, T. +16 more
The spectrum of Saturn has been recorded between 4.5 and 16.0µm with the grating mode of the Short-Wavelength Spectrometer (SWS) of ISO. The resolving power is 1500. The main results of this observation are (1) the detection of CO_2_, CH_3_C_2_H and C_4_H_2_ in the stratosphere and (2) the detection of H_2_O in the troposphere. In the 4.5-5.…
Infrared spectral energy distributions of the interacting galaxies ARP 244, NGC 6240, and ARP 220.
Schulz, B.; Klaas, U.; Heinrichsen, I. +1 more
For the luminous galaxies Arp 244, NGC 6240 and Arp 220 detailed infrared spectral energy distributions between 3 and 200µm obtained with ISOPHOT are presented. The maximum of the infrared energy distribution can now clearly be determined. The SEDs can be well represented by cold dust emission with temperatures of 30-50K which by far dominat…