Search Publications
The ERO Host Galaxy of GRB 020127: Implications for the Metallicity of GRB Progenitors
Berger, E.; Djorgovski, S. G.; Frail, D. A. +2 more
We present optical and near-IR observations of the host galaxy of GRB 020127, for which we measure R-Ks=6.2 mag. This is only the second GRB host to date classified as an ERO. The spectral energy distribution (SED) is typical of a dusty starburst galaxy, with a redshift z~1.9, a luminosity L~5L*, and an inferred stellar mass of M*<…
Venus as a more Earth-like planet
Witasse, Olivier; Taylor, Fredric W.; Svedhem, Håkan +1 more
Venus is Earth's near twin in mass and radius, and our nearest planetary neighbour, yet conditions there are very different in many respects. Its atmosphere, mostly composed of carbon dioxide, has a surface temperature and pressure far higher than those of Earth. Only traces of water are found, although it is likely that there was much more presen…
Effects of Downscattering on the Continuum and Line Spectra in a Powerful Wind Environment: Monte Carlo Simulations, Analytical Results, and Data Analysis
Laurent, Philippe; Titarchuk, Lev
In an earlier paper, the general formulation and results for photon reprocessing (downscattering) that included recoil and Comptonization effects due to divergence of the flow were presented. In a second paper we showed the Monte Carlo (MC) simulated continuum and line spectra. We also provided an analytical description of the simulated continuum …
The Cosmic Evolution Survey (COSMOS): A Large-Scale Structure at z=0.73 and the Relation of Galaxy Morphologies to Local Environment
Finoguenov, A.; Böhringer, H.; Kneib, J. -P. +29 more
We have identified a large-scale structure at z~=0.73 in the COSMOS field, coherently described by the distribution of galaxy photometric redshifts, an ACS weak-lensing convergence map, and the distribution of extended X-ray sources in a mosaic of XMM-Newton observations. The main peak seen in these maps corresponds to a rich cluster with TX<…
Galactic Bulges from Hubble Space Telescope NICMOS Observations: Global Scaling Relations
Balcells, Marc; Graham, Alister W.; Peletier, Reynier F.
We investigate bulge and disk scaling relations using a volume-corrected sample of early- to intermediate-type disk galaxies in which, importantly, the biasing flux from additional nuclear components has been modeled and removed. Structural parameters are obtained from a seeing-convolved, bulge + disk + nuclear-component decomposition applied to n…
Response of Jupiter's UV auroras to interplanetary conditions as observed by the Hubble Space Telescope during the Cassini flyby campaign
Nichols, J. D.; Clarke, J. T.; Cowley, S. W. H. +4 more
We provide a first detailed discussion of the relation between the set of Jovian UV auroral images observed by the Hubble Space Telescope (HST) in December 2000 to January 2001 and simultaneous interplanetary data obtained by Cassini during its Jupiter flyby. Examination of the interplanetary data surrounding all seven HST observation intervals sh…
The Extended Star Formation History of the Andromeda Spheroid at 21 kpc on the Minor Axis
Ferguson, Henry C.; Brown, Thomas M.; Gilbert, Karoline M. +8 more
Using the Hubble Space Telescope Advanced Camera for Surveys, we have obtained deep optical images of a southeast minor-axis field in the Andromeda galaxy, 21 kpc from the nucleus. In both star counts and metallicity, this field represents a transition zone between the metal-rich, highly disturbed inner spheroid that dominates within 15 kpc and th…
Ionized nebulae surrounding brightest cluster galaxies
Fabian, A. C.; Crawford, C. S.; Hatch, N. A.
We present integral field spectroscopic observations of six emission-line nebulae that surround the central galaxy of cool core clusters. Qualitatively similar nebulae are observed in cool core clusters even when the dynamics and possibly formation and excitation source are different. Evidence for a nearby secondary galaxy disturbing a nebula, as …
A Statistical Study of Shear Motion of the Footpoints in Two-Ribbon Flares
Golub, Leon; Su, Yingna; Van Ballegooijen, Adriaan A.
We present a statistical investigation of shear motion of the ultraviolet (UV) or extreme-ultraviolet (EUV) footpoints in two-ribbon flares, using the high spatial resolution data obtained in 1998-2005 by TRACE. To do this study, we have selected 50 well-observed X and M class two-ribbon flares as our sample. All 50 of these flares are classified …
Mechanical modeling of thrust faults in the Thaumasia region, Mars, and implications for the Noachian heat flux
Neukum, G.; Hauber, E.; Grott, M. +2 more
Insight into the state of the early martian lithosphere is gained by modeling the topography above surface breaking thrust faults in the southern Thaumasia region. Crater counts of key surface units associated with the faulting indicate a scarp emplacement in the late Noachian-early Hesperian periods between 4.0 and 3.7 Gyr. The seismogenic layer …