Search Publications
Ion escape from Mars as a function of solar wind conditions: A statistical study
Barabash, Stas; Lundin, Rickard; Nilsson, Hans +5 more
The influence of solar EUV and solar wind conditions on ion escape at Mars is investigated using ion data from the Aspera-3 instrument on Mars Express, combined with solar wind proxy data obtained from the Mars Global Surveyor (MGS) spacecraft. A solar EUV flux proxy based on data from the Earth position, scaled and shifted in time for Mars, is us…
SPIRE spectroscopy of the prototypical Orion Bar photodissociation region
Miville-Deschênes, M. -A.; Boulanger, F.; Abergel, A. +42 more
Aims: We present observations of the Orion Bar photodissociation region (PDR) obtained with the SPIRE instrument on-board Herschel.
Methods: We obtained SPIRE Fourier-transform spectrometer (FTS) sparse sampled maps of the Orion bar.
Results: The FTS wavelength coverage and sensitivity allow us to detect a wealth of rotational lines…
Nitrogen hydrides in interstellar gas. Herschel/HIFI observations towards G10.6-0.4 (W31C)
Perault, M.; Boulanger, F.; Falgarone, E. +49 more
The HIFI instrument on board the Herschel Space Observatory has been used to observe interstellar nitrogen hydrides along the sight-line towards G10.6-0.4 in order to improve our understanding of the interstellar chemistry of nitrogen. We report observations of absorption in NH N = 1 ≤ftarrow 0, J = 2 ≤ftarrow 1 and ortho-NH2 11,1<…
First results of Herschel-PACS observations of Neptune
Blommaert, J. A. D. L.; Lara, L. M.; Küppers, M. +51 more
We report on the initial analysis of a Herschel-PACS full range spectrum of Neptune, covering the 51-220 µm range with a mean resolving power of ~3000, and complemented by a dedicated observation of CH4 at 120 µm. Numerous spectral features due to HD (R(0) and R(1)), H2O, CH4, and CO are present, but so…
Photolysis of sulphuric acid as the source of sulphur oxides in the mesosphere of Venus
Montmessin, Franck; Bertaux, Jean-Loup; Zhang, Xi +3 more
The sulphur cycle plays fundamental roles in the chemistry and climate of Venus. Thermodynamic equilibrium chemistry at the surface of Venus favours the production of carbonyl sulphide and to a lesser extent sulphur dioxide. These gases are transported to the middle atmosphere by the Hadley circulation cell. Above the cloud top, a sulphur oxidatio…
Three-Dimensional View of Transient Horizontal Magnetic Fields in the Photosphere
Tsuneta, Saku; Jurčák, Jan; Ishikawa, Ryohko
We infer the three-dimensional magnetic structure of a transient horizontal magnetic field (THMF) during its evolution through the photosphere using SIRGAUS inversion code. The SIRGAUS code is a modified version of SIR (Stokes Inversion based on Response function), and allows for retrieval of information on the magnetic and thermodynamic parameter…
The CHESS spectral survey of star forming regions: Peering into the protostellar shock L1157-B1. II. Shock dynamics
Falgarone, E.; Maret, S.; Henning, T. +74 more
Context. The outflow driven by the low-mass class 0 protostar L1157 is the prototype of the so-called chemically active outflows. The bright bowshock B1 in the southern outflow lobe is a privileged testbed of magneto-hydrodynamical (MHD) shock models, for which dynamical and chemical processes are strongly interdependent.
Aims: We present the…
In-flight calibration of the Cassini imaging science sub-system cameras
McEwen, Alfred; Porco, Carolyn; West, Robert +10 more
We describe in-flight calibration of the Cassini Imaging Science Sub-system narrow- and wide-angle cameras using data from 2004 to 2009. We report on the photometric performance of the cameras including the use of polarization filters, point spread functions over a dynamic range greater than 10 7, gain and loss of hot pixels, changes in…
Signature of wide-spread clumping in B supergiant winds
Prinja, R. K.; Massa, D. L.
Aims: We seek to establish additional observational signatures of the effects of clumping in OB star winds. The action of clumping on strategic wind-formed spectral lines is tested to steer the development of models for clumped winds and thus improve the reliability of mass-loss determinations for massive stars.
Methods: The Siiv λλ1400 …
Outlying H II Regions in H I-Selected Galaxies
Freeman, K. C.; Ferguson, H. C.; Smith, R. C. +21 more
We present results from the first systematic search for outlying H II regions, as part of a sample of 96 emission-line point sources (referred to as ELdots-emission-line dots) derived from the NOAO Survey for Ionization in Neutral Gas Galaxies (SINGG). Our automated ELdot finder searches SINGG narrowband and continuum images for high equivalent wi…