Search Publications
Forming Early-Type Galaxies in Groups Prior to Cluster Assembly
Tran, Kim-Vy H.; Moustakas, John; Gonzalez, Anthony H. +3 more
We study a unique protocluster of galaxies, the supergroup SG1120-1202. We quantify the degree to which morphological transformation of cluster galaxies occurs prior to cluster assembly in order to explain the observed early-type fractions in galaxy clusters at z = 0. SG1120-1202 at z ~ 0.37 is composed of four gravitationally bound groups that ar…
Gusev photometric variability as seen from orbit by HRSC/Mars-express
Scholten, F.; Neukum, G.; Pinet, P. +12 more
Minnaert and two-term phase function Hapke models are used to describe the photometric properties of the martian surface using HRSC (High Resolution Stereo Camera) multi-angular observations acquired along the ongoing Mars-Express mission. These observations can be pieced together to derive integrated phase functions over a wide range of phase ang…
Plasma convection in Saturn's outer magnetosphere determined from ions detected by the Cassini INCA experiment
Krimigis, S. M.; Mitchell, D. G.; Carbary, J. F. +2 more
The Ion and Neutral Camera (INCA), one of three sensors comprising the Magnetospheric Imaging Instrument (MIMI) on the Cassini spacecraft, measures intensities of hydrogen and oxygen ions and neutral atoms in the Saturnian magnetosphere. The measured intensity spectrum and anisotropy of hot hydrogen and oxygen ions may be used to deduce the spectr…
Gamma-ray bursts from the early Universe: predictions for present-day and future instruments
Covino, S.; Campana, S.; Tagliaferri, G. +2 more
Long gamma-ray bursts (GRBs) are important for the study of the Universe near and beyond the epoch of reionization. In this paper, we describe the characteristics of an `ideal' instrument that can be used to search for GRBs at z >= 6-10. We find that the detection of these objects requires soft-band detectors with high sensitivity and a moderat…
The methane abundance and structure of Uranus' cloud bands inferred from spatially resolved 2006 Keck grism spectra
Sromovsky, L. A.; Fry, P. M.
Grism spectra of Uranus obtained at the Keck Observatory in 2006, using the NIRC2 instrument and adaptive optics, provide new constraints on the vertical structure of Uranus' cloud bands and on the volume mixing ratio of methane. The best model fits to H-band spectra (1.49-1.635 µm) are found for a methane volume mixing ratio of 1.0 ± 0.25% …
The reflectance spectrum of Titan's surface at the Huygens landing site determined by the descent imager/spectral radiometer
Keller, H. U.; Schröder, S. E.
The descent imager/spectral radiometer aboard the Huygens probe successfully acquired images and spectra of the surface of Titan. To counter the effects of haze and atmospheric methane absorption it carried a surface science lamp to illuminate the surface just before landing. We reconstruct the reflectance spectrum of the landing site in the 500-1…
Influence of high abundances of aerosols on the electrical conductivity of the Titan atmosphere
Whitten, R. C.; Borucki, W. J.
Observations of optical depth and scattering by instrumentation onboard the Huygens probe have been used by Tomasko et al. [Tomasko et al., 2005. Rain, winds and haze during Huygens probe's descent to Titan's surface. Nature 438 (8), 765-778] to deduce that the size and abundance of Titan aerosols could be nearly independent of altitude. Here we s…
The molecular polar disc in NGC 2768
Bureau, Martin; Crocker, Alison F.; Young, Lisa M. +1 more
We present CO(1-0) and CO(2-1) maps of the molecular polar disc in the elliptical galaxy NGC 2768 obtained at the Institute de Radioastronomie Millimétrique (IRAM) Plateau de Bure Interferometer. The maps have a resolution of and for the CO(1-0) and CO(2-1) lines, respectively. The CO maps complete the unique picture of the interstellar medium (IS…
Non-parametric strong lens inversion of Cl 0024+1654: illustrating the monopole degeneracy
de Rijcke, S.; Dejonghe, H.; Liesenborgs, J. +1 more
The cluster lens Cl 0024+1654 is undoubtedly one of the most beautiful examples of strong gravitational lensing, providing five large images of a single source with well-resolved substructure. Using the information contained in the positions and the shapes of the images, combined with the null space information, a non-parametric technique is used …
An assessment of the role of the centrifugal acceleration mechanism in high altitude polar cap oxygen ion outflow
Lundin, R.; Yamauchi, M.; Sauvaud, J. -A. +11 more
The role of the centrifugal acceleration mechanism for ion outflow at high altitude above the polar cap has been investigated. Magnetometer data from the four Cluster spacecraft has been used to obtain an estimate of magnetic field gradients. This is combined with ion moment data of the convection drift and the field-aligned particle velocity. Thu…