Search Publications
Calibration of the Planetary Fourier Spectrometer long wavelength channel
Piccioni, G.; Grassi, D.; Khatuntsev, I. +17 more
The Planetary Fourier Spectrometer (PFS) experiment on board the Mars Express mission has two channels covering the 1.2-5 µm (SWC) and the 5-50 µm (LWC). The Long Wavelength Channel (LWC) measures the thermal emission spectrum of Mars between 200 and 2000 cm -1 with a spectral resolution of 1.4 cm -1, in absence o…
A study of bright Southern long period variables
Lebzelter, T.; Hinkle, K. H.; Wood, P. R. +2 more
In this paper we present radial velocity curves of AGB variables that exhibit various kinds of anomalies: semiregular variables (SRVs) with typical mira periods, SRVs exceeding the mira 2.5 mag amplitude limit, miras with secondary maxima in their light curves, and a SRV with a long secondary period. The stars with reliable Hipparcos parallaxes fr…
HST/WFPC2 morphologies and bar structures of field galaxies at 0.4 < z < 1
Flores, H.; Hammer, F.; Assémat, F. +2 more
To address how the galaxy Hubble sequence is established and what physical processes are involved, we studied morphological properties and internal structures of field galaxies in the past (0.4<z<1). In addition to structural parameters derived from bulge+disk decomposition, Zheng et al. (2004, A&A, 421, 847) introduced color maps in rec…
Star-forming accretion flows and the low-luminosity nuclei of giant elliptical galaxies
Tan, Jonathan C.; Blackman, Eric G.
The luminosities of the centres of nearby elliptical galaxies are very low compared to models of thin disc accretion on to their black holes at the Bondi rate, typically a few hundredths to a few tenths of a solar mass per year. This has motivated models of inefficiently radiated accretion that invoke weak electron-ion thermal coupling, and/or inh…
A Dynamical Simulation of the Debris Disk around HD 141569A
Ford, H. C.; Infante, L.; Zheng, W. +36 more
We study the dynamical origin of the structures observed in the scattered-light images of the resolved debris disk around HD 141569A. The disk has two conspicuous spiral rings and two large-scale spiral arms. We explore the roles of radiation pressure from the central star, gas drag from the gas disk, and the tidal forces from two nearby stars in …
Intrinsic Absorption in the Spectrum of NGC 7469: Simultaneous Chandra, FUSE, and STIS Observations
Kaiser, Mary Elizabeth; Green, Richard F.; Scott, Jennifer E. +10 more
We present simultaneous X-ray, far-ultraviolet, and near-ultraviolet spectra of the Seyfert 1 galaxy NGC 7469 obtained with the Chandra X-Ray Observatory, the Far Ultraviolet Spectroscopic Explorer, and the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. Previous nonsimultaneous observations of this galaxy found two distinct UV…
Radar imaging of Saturn's rings
Nicholson, Philip D.; French, Richard G.; Campbell, Donald B. +4 more
We present delay-Doppler images of Saturn's rings based on radar observations made at Arecibo Observatory between 1999 and 2003, at a wavelength of 12.6 cm and at ring opening angles of 20.1°⩽|B|⩽26.7°. The average radar cross-section of the A ring is ∼77% relative to that of the B ring, while a stringent upper limit of 3% is placed on the cross-s…
Mid-infrared imaging of NGC 1068 with VISIR at the Very Large Telescope
Pantin, E.; Alloin, D.; Galliano, E. +1 more
High-resolution mid-infrared (MIR) images of the central region of NGC 1068 have been obtained with VISIR, the multi-mode MIR instrument recently installed at the European Southern Observatory Very Large Telescope on Paranal. A map of the emission at 12.8 µm with increased sensitivity over the central 8 × 8 arcsec2 area is discuss…
An ISOCAM survey through gravitationally lensing galaxy clusters. IV. Luminous infrared galaxies in Cl 0024+1654 and the dynamical status of clusters
Kneib, J. -P.; Altieri, B.; Miville-Deschênes, M. -A. +9 more
Observations of the core of the massive cluster
On the effect of the background wind on the evolution of interplanetary shock waves
Poedts, S.; Chané, E.; Jacobs, C. +1 more
The propagating shock waves in the solar corona and interplanetary (IP) space caused by fast Coronal Mass Ejections (CMEs) are simulated numerically and their structure and evolution is studied in the framework of ideal magnetohydrodynamics (MHD). Due to the presence of three characteristic velocities and the anisotropy induced by the magnetic fie…