Search Publications
An improvement to the volcano-scan algorithm for atmospheric correction of CRISM and OMEGA spectral data
Seelos, Frank P.; Murchie, Scott L.; Mustard, John F. +12 more
The observations of Mars by the CRISM and OMEGA hyperspectral imaging spectrometers require correction for photometric, atmospheric and thermal effects prior to the interpretation of possible mineralogical features in the spectra. Here, we report on a simple, yet non-trivial, adaptation to the commonly-used volcano-scan correction technique for at…
The structures of distant galaxies - III. The merger history of over 20000 massive galaxies at z < 1.2
Conselice, Christopher J.; Bluck, Asa F. L.; Yang, Cui
Utilizing deep Hubble Space Telescope imaging from the two largest field galaxy surveys, the Extended Groth Strip and the Cosmic Evolution Survey (COSMOS), we examine the structural properties, and derive the merger history for 21902 galaxies with M* > 1010Msolar at z < 1.2. We examine the structural concentr…
The bolometric luminosity of type 2 AGN from extinction-corrected [OIII]. No evidence of Eddington-limited sources
Perola, G. C.; Bianchi, S.; Barcons, X. +3 more
Context: There have been recent claims that a significant fraction of type 2 AGN accrete close to or even above the Eddington limit. In type 2 AGN, the bolometric luminosity (L_b) is generally inferred from the [OIII] emission line luminosity (L_OIII). The key issue in estimating the bolometric luminosity in these AGN, is therefore to know the bol…
X-ray absorption and reflection in active galactic nuclei
Turner, T. J.; Miller, L.
X-ray spectroscopy offers an opportunity to study the complex mixture of emitting and absorbing components in the circumnuclear regions of active galactic nuclei (AGN), and to learn about the accretion process that fuels AGN and the feedback of material to their host galaxies. We describe the spectral signatures that may be studied and review the …
Energy Spectra of the Soft X-Ray Diffuse Emission in Fourteen Fields Observed with Suzaku
Fujimoto, Ryuichi; Yamasaki, Noriko Y.; Wang, Q. Daniel +8 more
The soft diffuse X-ray emission of twelve fields observed with Suzaku are presented together with two additional fields from previous analyses. All have galactic longitudes 65° < l < 295° to avoid contributions from the very bright diffuse source that extends at least 30° from the Galactic center. The surface brightnesses of the Suzaku nine …
Longitudinal Waves in Coronal Loops
de Moortel, I.
Outwardly propagating intensity disturbances are a common feature in large, quiescent coronal loop structures. In this paper, an overview is given of the observed properties and the theoretical modelling. As a large number of events have been observed and analysed, good statistical results on the estimated parameters have now been obtained. The th…
Magnetic activity in the photosphere of CoRoT-Exo-2a. Active longitudes and short-term spot cycle in a young Sun-like star
Aigrain, S.; Alonso, R.; Auvergne, M. +18 more
Context: The space experiment CoRoT has recently detected transits by a hot Jupiter across the disc of an active G7V star (CoRoT-Exo-2a) that can be considered as a good proxy for the Sun at an age of approximately 0.5 Gyr.
Aims: We present a spot modelling of the optical variability of the star during 142 days of uninterrupted observations pe…
Deep U Band and R Imaging of Goods-South: Observations, Data Reduction and First Results
Daddi, E.; Cesarsky, C.; Dickinson, M. +9 more
We present deep imaging in the U band covering an area of 630 arcmin2 centered on the southern field of the Great Observatories Origins Deep Survey (GOODS). The data were obtained with the VIMOS instrument at the European Southern Observatory (ESO) Very Large Telescope. The final images reach a magnitude limit U lim ≈ 29.8 (A…
Dynamical Masses of Early-Type Galaxies at z ~ 2: Are they Truly Superdense?
Cimatti, A.; Daddi, E.; Rodighiero, G. +11 more
We measured stellar velocity dispersions σ and derived dynamical masses of nine massive (M ≈ 1011 M sun) early-type galaxies (ETGs) from the Galaxy Mass Assembly ultra-deep Spectroscopic Survey (GMASS) sample at redshift 1.4 lsim z lsim 2.0. The σ are based on individual spectra for two galaxies at z ≈ 1.4 and on a stacked sp…
X-Ray Microlensing in RXJ1131-1231 and HE1104-1805
Kochanek, C. S.; Dai, X.; Chartas, G. +2 more
We present results from a monitoring campaign performed with the Chandra X-ray Observatory of the gravitationally lensed quasars RX J1131-1231 and HE 1104-1805. We detect significant X-ray variability in all images of both quasars. The flux variability detected in image A of RX J1131-1231 is of particular interest because of its high amplitude (a …