Search Publications
Warm water vapour in the sooty outflow from a luminous carbon star
Ivison, R. J.; Blommaert, J. A. D. L.; Olofsson, G. +34 more
The detection of circumstellar water vapour around the ageing carbon star IRC +10216 challenged the current understanding of chemistry in old stars, because water was predicted to be almost absent in carbon-rich stars. Several explanations for the water were postulated, including the vaporization of icy bodies (comets or dwarf planets) in orbit ar…
Supraglacial and proglacial valleys on Amazonian Mars
Head, James W.; Fassett, Caleb I.; Levy, Joseph S. +2 more
Abundant evidence exists for glaciation being an important geomorphic process in the mid-latitude regions of both hemispheres of Mars, as well as in specific environments at near-equatorial latitudes, such as along the western flanks of the major Tharsis volcanoes. Detailed analyses of glacial landforms (lobate-debris aprons, lineated valley fill,…
Determining dust temperatures and masses in the Herschel era: The importance of observations longward of 200 micron
Bernard, J. -P.; Reach, W. T.; Okumura, K. +21 more
Context. The properties of the dust grains (e.g., temperature and mass) can be derived from fitting far-IR SEDs (≥100 µm). Only with SPIRE on Herschel has it been possible to get high spatial resolution at 200 to 500 µm that is beyond the peak (~160 µm) of dust emission in most galaxies.
Aims: We investigate the differences …
The Importance of Nebular Continuum and Line Emission in Observations of Young Massive Star Clusters
Nidever, David L.; Johnson, Kelsey E.; Reines, Amy E. +1 more
In this spectroscopic study of infant massive star clusters, we find that continuum emission from ionized gas rivals the stellar luminosity at optical wavelengths. In addition, we find that nebular line emission is significant in many commonly used broadband Hubble Space Telescope (HST) filters including the F814W I-band, the F555W V-band, and the…
Quasi-Periodic Pulsations in the Gamma-Ray Emission of a Solar Flare
Foullon, C.; Nakariakov, V. M.; Myagkova, I. N. +1 more
Quasi-periodic pulsations (QPPs) of gamma-ray emission with a period of about 40 s are found in a single loop X-class solar flare on 2005 January 1 at photon energies up to 2-6 MeV with the SOlar Neutrons and Gamma-rays (SONG) experiment aboard the CORONAS-F mission. The oscillations are also found to be present in the microwave emission detected …
A Reconnecting Current Sheet Imaged in a Solar Flare
Liu, Chang; Wang, Haimin; Stenborg, Guillermo +3 more
Magnetic reconnection changes the magnetic field topology and powers explosive events in astrophysical, space, and laboratory plasmas. For flares and coronal mass ejections (CMEs) in the solar atmosphere, the standard model predicts the presence of a reconnecting current sheet, which has been the subject of considerable theoretical and numerical m…
Influence of spacecraft outgassing on the exploration of tenuous atmospheres with in situ mass spectrometry
Wurz, P.; Altwegg, K.; Balsiger, H. +10 more
In situ mass spectrometry has been a powerful tool in many space missions to investigate atmospheres and exospheres of different bodies in the solar system. Applying new technologies, the mass spectrometers have become increasingly more sensitive. In this study, we show that spacecraft outgassing, which can never be completely prevented, will be t…
Velocity vectors of a quiescent prominence observed by Hinode/SOT and the MSDP (Meudon)
Schmieder, B.; Chandra, R.; Berlicki, A. +1 more
Context. The dynamics of prominence fine structures present a challenge to our understanding of the formation of cool plasma prominence embedded in the hot corona.
Aims: Observations performed by the high resolution Hinode/SOT telescope allow us to compute velocities perpendicular to the line-of-sight or transverse velocities. Combining simul…
A transiting giant planet with a temperature between 250K and 430K
Mazeh, T.; Aigrain, S.; Alonso, R. +58 more
Of the over 400 known exoplanets, there are about 70 planets that transit their central star, a situation that permits the derivation of their basic parameters and facilitates investigations of their atmospheres. Some short-period planets, including the first terrestrial exoplanet (CoRoT-7b), have been discovered using a space mission designed to …
Hydrides in young stellar objects: Radiation tracers in a protostar-disk-outflow system
de Graauw, Th.; Liseau, R.; Braine, J. +66 more
Context. Hydrides of the most abundant heavier elements are fundamental molecules in cosmic chemistry. Some of them trace gas irradiated by UV or X-rays.
Aims: We explore the abundances of major hydrides in W3 IRS5, a prototypical region of high-mass star formation.
Methods: W3 IRS5 was observed by HIFI on the Herschel Space Observatory …