Search Publications
Mars ultraviolet dayglow variability: SPICAM observations and comparison with airglow model
Bertaux, J. -L.; Gérard, J. -C.; Hubert, B. +2 more
Dayglow ultraviolet emissions of the CO Cameron bands and the CO2+ doublet in the Martian atmosphere have been observed with the Spectroscopy for Investigation of Characteristics of the Atmosphere of Mars on board the Mars Express spacecraft. A large amount of limb profiles has been obtained which makes it possible to analyze…
The DAFT/FADA survey. I. Photometric redshifts along lines of sight to clusters in the z = [0.4, 0.9] interval
Ilbert, O.; Schrabback, T.; Allam, S. +20 more
Context. As a contribution to the understanding of the dark energy concept, the Dark energy American French Team (DAFT, in French FADA) has started a large project to characterize statistically high redshift galaxy clusters, infer cosmological constraints from weak lensing tomography, and understand biases relevant for constraining dark energy and…
A search for molecules in the atmosphere of HD 189733b
Pinfield, D. J.; Collier Cameron, A.; Barnes, J. R. +7 more
We use signal enhancement techniques and a matched filter analysis to search for the K-band spectroscopic absorption signature of the close orbiting extrasolar giant planet, HD 189733b. With time-series observations taken with the Near Infrared Spectrometer (NIRSPEC) at Keck II, we investigate the relative abundances of H2O and carbon b…
A long hard look at the minimum state of PG 2112+059 with XMM-Newton
Schartel, N.; Rodríguez-Pascual, P. M.; Santos-Lleó, M. +3 more
Aims: Our observational aim is to perform a long X-ray observation of the quasar PG 2112+059 in its low or minimum state. Starting form this very peculiar emission state, we intend to constrain the intrinsic emission mechanism by comparing new and old data, corresponding to different source states.
Methods: XMM-Newton successfully detect…
Suzaku Monitoring of the Seyfert 1 Galaxy NGC 5548: Warm Absorber Location and Its Implication for Cosmic Feedback
Liu, Y.; Binette, L.; Elvis, M. +12 more
We present a 2 month Suzaku X-ray monitoring of the Seyfert 1 galaxy NGC 5548. The campaign consists of seven observations (with exposure time of ~30 ks each), separated by ~1 week. This paper focus on the X-ray Imaging Spectrometer data of NGC 5548. We analyze the response in the opacity of the gas that forms the well-known ionized absorber in th…
Impact-induced overland fluid flow and channelized erosion at Lyot Crater, Mars
Harrison, Tanya N.; Malin, Michael C.; Cantor, Bruce A. +5 more
Lyot Crater is one of the youngest impact basins > 200 km in diameter on Mars. Although published hydrological models suggest that impact-related groundwater release might have occurred at Lyot, no geomorphic evidence for such activity has been previously identified. Here, we use images acquired predominantly by the Mars Reconnaissance Orbiter …
Evolution of the Synchrotron and Inverse Compton Emissions of the Low-energy-peaked BL Lac Object S5 0716+714
Zhang, Y. H.
This paper presents a detailed analysis of the temporal and spectral variability of the low-energy peaked BL Lac object S5 0716+714 with a long (~74 ks) X-ray observation performed by XMM-Newton on 2007 September 24-25. The source experiences recurrent flares on timescales of hours. The soft X-ray variations, up to a factor of ~4, are much stronge…
Gas Emission from Debris Disks Around A and F Stars
Brandeker, Alexis; Wu, Yanqin; Zagorovsky, Kyryl
Gas has been detected in a number of debris disk systems. This gas may have arisen from grain sublimation or grain photodesorption. It interacts with the surrounding dust grains through a number of charge and heat exchanges. Studying the chemical composition and physical state of this gas can therefore reveal much about the dust component in these…
On the "Extended" Solar Cycle in Coronal Emission
Sheeley, N. R., Jr.; Wang, Y. -M.; Rich, N. B. +1 more
Butterfly diagrams (latitude-time plots) of coronal emission show a zone of enhanced brightness that appears near the poles just after solar maximum and migrates toward lower latitudes; a bifurcation seems to occur at sunspot minimum, with one branch continuing to migrate equatorward with the sunspots of the new cycle and the other branch heading …
Automatic Detection and Extraction of Coronal Dimmings from SDO/AIA Data
Wills-Davey, M. J.; Attrill, G. D. R.
The volume of data anticipated from the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) highlights the necessity for the development of automatic-detection methods for various types of solar activity. Initially recognized in the 1970s, it is now well established that coronal dimmings are closely associated with coronal mass eject…