Search Publications
The Nitrogen Chemistry of Titan's Upper Atmosphere Revealed
Yelle, R. V.; Vuitton, V.; Anicich, V. G.
Titan's atmosphere is unique because dissociation of N2 and CH4, the primary atmospheric constituents, provides the H, C, and N atoms necessary for the synthesis of complex organic molecules. The first steps in the synthesis of organic molecules occur in the upper atmosphere where energetic photons and electrons dissociate N<…
Cepheid Distances to SNe Ia Host Galaxies Based on a Revised Photometric Zero Point of the HST WFPC2 and New PL Relations and Metallicity Corrections
Saha, A.; Tammann, G. A.; Thim, F. +2 more
With this paper we continue the preparation for a forthcoming summary report of our experiment with the HST to determine the Hubble constant using Type Ia supernovae as standard candles. Two problems are addressed. (1) We examine the need for, and determine the value of, the corrections to the apparent magnitudes of our program Cepheids in the 11 …
The unprecedented optical outburst of the quasar 3C 454.3 . The WEBT campaign of 2004-2005
Lee, C. -U.; Lähteenmäki, A.; Umana, G. +85 more
Context: .The radio quasar
Aims: .In order to follow the emission behaviour of the …
The X-ray nuclei of intermediate-redshift radio sources
Hardcastle, M. J.; Croston, J. H.; Evans, D. A.
We present a Chandra and XMM-Newton spectral analysis of the nuclei of the radio galaxies and radio-loud quasars from the 3CRR sample in the redshift range 0.1 < z < 0.5. In the range of radio luminosity sampled by these objects, mostly Fanaroff-Riley type IIs (FR IIs), it has been clear for some time that a population of radio galaxies [low…
A Survey of Galaxy Kinematics to z~1 in the TKRS/GOODS-N Field. I. Rotation and Dispersion Properties
Weiner, Benjamin J.; Faber, S. M.; Willmer, Christopher N. A. +7 more
We present kinematic measurements of a large sample of galaxies from the Team Keck Redshift Survey in the GOODS-N field. We measure line-of-sight velocity dispersions from integrated emission for 1089 galaxies with median redshift 0.637 and spatially resolved kinematics for a subsample of 380 galaxies. This is the largest sample of galaxies to z~1…
3D spectroscopy with VLT/GIRAFFE. I. The true Tully Fisher relationship at z ∼ 0.6
Flores, H.; Hammer, F.; Puech, M. +2 more
A precise derivation of the evolution of the Tully Fisher is crucial to understand the interplay between dark matter and baryonic matter in cosmological models, using 15 deployable integral field units of FLAMES/GIRAFFE at VLT, we have recovered the velocity fields of 35 galaxies at intermediate redshift (0.4 < z < 0.75). This facility is ab…
Cosmic Evolution of Black Holes and Spheroids. I. The MBH-σ Relation at z = 0.36
Treu, Tommaso; Malkan, Matthew A.; Blandford, Roger D. +1 more
We test the evolution of the correlation between black hole mass and bulge velocity dispersion (MBH-σ), using a carefully selected sample of 14 Seyfert 1 galaxies at z=0.36+/-0.01. We measure velocity dispersion from stellar absorption lines around Mg b (5175 Å) and Fe (5270 Å) using high-S/N Keck spectra and estimate black hole mass fr…
Anisotropic Turbulent Spectra in the Terrestrial Magnetosheath as Seen by the Cluster Spacecraft
Balogh, A.; Belmont, G.; Sahraoui, F. +3 more
Here we report the first three-dimensional spatial spectrum of the low frequency magnetic turbulence obtained from the four Cluster spacecraft in the terrestrial magnetosheath close to the magnetopause. We show that the turbulence is compressible and dominated by mirror structures, its energy is injected at a large scale kρ∼0.3 (l∼2000 km) via a m…
The Large-Scale and Small-Scale Clustering of Lyman Break Galaxies at 3.5<=z<=5.5 from the GOODS Survey
Ouchi, Masami; Dickinson, Mark; Ferguson, Henry C. +4 more
We report on the angular correlation function of Lyman break galaxies (LBGs) at z~4 and 5 from deep samples obtained from the Great Observatories Deep Origins Survey (GOODS). As for LBGs at z~3, the shape of w(θ) of the GOODS LBGs is well approximated by a power law with a slope β~0.6 at angular separation θ>=10". The clustering strength of the…
The Rest-Frame Far-Ultraviolet Morphologies of Star-forming Galaxies at z ~ 1.5 and 4
Ferguson, Henry C.; Giavalisco, Mauro; Lotz, Jennifer M. +2 more
We apply a new approach to quantifying galaxy morphology and identifying galaxy mergers to the rest-frame far-ultraviolet images of 82 z~4 Lyman break galaxies (LBGs) and 55 1.2<z<1.8 emission-line galaxies in the GOODS and Ultra Deep Field survey. We compare the distributions of the Gini coefficient (G), the second-order moment of the brigh…