Search Publications
Advanced Camera for Surveys Observations of a Strongly Lensed Arc in a Field Elliptical Galaxy
Ford, H. C.; Infante, L.; Zheng, W. +15 more
We report the discovery of a strongly lensed arc system around a field elliptical galaxy in Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) images of a parallel field observed during NICMOS observations of the HST Ultra Deep Field. The ACS parallel data comprise deep imaging in the F435W, F606W, F775W, and F850LP bandpasses. The mai…
The far-infrared spectra of Jupiter and Saturn
Lellouch, E.; Encrenaz, T.; Orton, G. S. +4 more
We present far-infrared, disk-averaged spectra of Jupiter and Saturn that were measured with the Long Wavelength Spectrometer aboard the Infrared Space Observatory. The Long Wavelength Spectrometer covered the wavelength region between 43 and 197 µm and achieved in grating mode a resolving power of 150-300.
The spectra observed in the f…X-ray emission from a brown dwarf in the Pleiades
Briggs, K. R.; Pye, J. P.
We report on the first detection of X-ray emission from a brown dwarf in the Pleiades, the M7-type Roque 14, obtained using the EPIC detectors on XMM-Newton. This is the first X-ray detection of a brown dwarf intermediate in age between ~12 and ~320 Myr. The emission appears persistent, although we cannot rule out flare-like behaviour with a decay…
Europa's opposition surge in the near-infrared: interpreting disk-integrated observations by Cassini VIMS
Buratti, Bonnie J.; Simonelli, Damon P.
Near-infrared observations of Europa's disk-integrated opposition surge by Cassini VIMS, first published in Fig. 4 of Brown et al. (2003, Icarus, 164, 461), have now been modeled with the commonly used Hapke photometric function. The VIMS data set emphasizes observations at 16 solar phase angles from 0.4° to 0.6°—the first time the <1° phase "h…
Atomic Data and Spectral Line Intensities for Ca VIII
Landi, E.; Storey, P. J.; Zeippen, C. J.
In the present work a complete set of energy levels, spontaneous radiative decay rates, and thermally averaged collision strengths are calculated for the first time for the five lowest electron configurations of Ca VIII, corresponding to 40 fine-structure energy levels. Collision data are calculated using the R-matrix approximation, and results ar…
Shumann resonances and electromagnetic transparence in the atmosphere of Titan
Molina-Cuberos, G. J.; Eichelberger, H. U.; Schwingenschuh, K. +6 more
Among the multiple questions that the CASSINI/HUYGENS mission tries to answer is the likelihood of electric discharges in Titan's atmosphere. The instruments ``Huygens Atmospheric Structure Instrument'' and ``Radio and Plasma Wave Science'' will probe the electromagnetic emissions during the Huygens descent and Cassini flybys, respectively. Althou…
Upper limits on hydrogen halides in Jupiter from Cassini/CIRS observations
Nixon, Conor A.; Irwin, Patrick G. J.; Fouchet, Thierry +2 more
We have determined the following upper limits for the mole fraction of hydrogen halides in Jupiter's atmosphere from Cassini/CIRS observations: [HF] <2.7×10 -11, [HCl] <2.3×10 -9, [HBr] <1.0×10 -9, [HI] <7.6×10 -9. These limits are smaller than solar composition for HF and HCl, and support th…
The Geneva-Copenhagen Survey of the Solar Neighbourhood
Pont, F.; Holmberg, J.; Nordström, B. +3 more
We report on a new survey of metallicities, ages, and Galactic orbits for a complete, magnitude-limited, and kinematically unbiased all-sky sample of 16682 nearby F- and G-dwarfs. Our~63000 new, accurate radial velocities for nearly 13500 of the stars, combined with Hipparcos parallaxes and Tycho-2 proper motions, complete the kinematic data for 1…
The unusual morphology of the intragroup medium in NGC 5171
Finoguenov, Alexis; Ponman, Trevor J.; Osmond, J. P. F.
We present the results of a 24-ks XMM-Newton observation of the NGC 5171 group of galaxies. NGC 5171 is unusual in that it is an X-ray bright group (LX > 1042 erg s-1), with irregular contours which are not centred on a bright galaxy. The global spectrum is adequately described by a single-temperature APEC model…
Conversion of bulk kinetic energy into radiation in AGNs and GRBs: Particle transport effects
Vainio, R.; Schlickeiser, R.; Pohl, M.
We investigate the spatial structure of collisionless collision fronts in relativistic outflows interacting with ambient material. As a result of the interaction, ambient particles are picked up by the outflow and generate transverse plasma waves via streaming instabilities. Pick-up particle transport under the influence of self-generated turbulen…