Search Publications
Variations of the He II λ1640 line in B0e-B2.5e stars
Smith, M. A.
Using the International Ultraviolet Explorer data archive, we have examined the SWP echellograms of 74 B0-B2.5e stars for statistically significant fluctuations in the He II ("Hα") λ1640 line profile. In this sample we found that the He II line is occasionally variable in 10 stars over short to long timescales. The He II-variable stars discovered …
Curvelet analysis of asteroseismic data. I. Method description and application to simulated sun-like stars
García, R. A.; Starck, J. -L.; Pires, S. +3 more
Context: .The detection and identification of oscillation modes (in terms of their ℓ, m, and successive n) is a great challenge for present and future asteroseismic space missions. "Peak tagging" is an important step in the analysis of these data to provide estimations of stellar oscillation mode parameters, i.e., frequencies, rotation rates, and …
ZEN and the search for high-redshift galaxies
Kneib, Jean-Paul; Minniti, Dante; Courbin, Frédéric +1 more
We present the ZEN ( z equals nine) survey: a deep, narrow J-band search for proto-galactic Ly α emission at redshifts z ∼ 9. In the first phase of the survey, dubbed ZEN1, we combine an exceptionally deep image of the Hubble Deep Field South, obtained using a narrow-band filter centred on the wavelength 1.187 µm, with existing deep, broad b…
Structure and kinematics of the interstellar medium in the star-forming region in the BCD galaxy VII Zw 403 (UGC 6456)
Moiseev, A. V.; Lozinskaya, T. A.; Egorov, O. V. +1 more
The structure and kinematics of ionized supershells in the star-forming region in the BCD galaxy VII Zw 403 (UGC 6456) are analyzed using observations with the SCORPIO focal reducer on the 6-m Special Astrophysical Observatory telescope in three modes: direct imaging (in the Hα, [O III], and [S II] lines), long-slit spectroscopy, and spectroscopy …
Electrodynamics of a split-transpolar aurora
RèMe, H.; Lester, M.; Dunlop, M. W. +6 more
We report new results on the relation between drift velocity shear, average inverted V energy, and the separation of bifurcated high-latitude Sun-aligned polar arcs within a global transpolar auroral arc system. The two parallel arcs appeared at the location of converging -v × B electric field of two sunward flow channels that were separated by an…
Photoelectric radial velocities, Paper XVII The orbits of 30 spectroscopic binaries in the southern Clube Selected Areas
Griffin, R. F.
Three of the six southern Clube Areas that were mainly observed at the European Southern Observatory and whose principal results are given in Paper XVI are marginally observable from Haute-Provence. Additional measurements obtained on several observing runs there enabled orbits to be determined (in most cases rather poorly, owing to the paucity of…
XMM-Newton survey of two upper Scorpius regions
Micela, G.; Peres, G.; Favata, F. +4 more
Aims.We studied X-ray emission from young stars by analyzing the deep XMM-Newton observations of two regions of the Upper Scorpius association with an age of 5 Myr.
Methods: .Based on near infrared and optical photometry we identified 22 Upper Scorpius photometric members among the 224 detected X-ray sources. We derived coronal properties of U…
ESO imaging survey: optical follow-up of 12 selected XMM-Newton fields
Motch, C.; Zaggia, S.; Watson, M. G. +12 more
This paper presents the data recently released for the XMM-Newton/WFI survey carried out as part of the ESO Imaging Survey (EIS) project. The aim of this survey is to provide optical imaging follow-up data in BVRI for identification of serendipitously detected X-ray sources in selected XMM-Newton fields. In this paper, fully calibrated individual …
Reconstructing the weather on Mars at the time of the MERs and Beagle 2 landings
Withers, P.; Lewis, S. R.; Read, P. L. +1 more
We reconstruct the temperature, wind and density structure of the atmosphere on Mars from the surface to 120 km altitude at the time of the landing of the two NASA Mars Exploration Rovers (MER), and ESA's ``Beagle 2.'' This reconstruction is based on an assimilation of temperature and dust opacity observations from the Thermal Emission Spectromete…
The thermosphere of Venus and its exploration by a Venus Express Accelerometer Experiment
Müller-Wodarg, I. C. F.; Forbes, J. M.; Keating, G. M.
The forthcoming observations by Venus Express provide an ideal opportunity to comprehensively study the atmosphere of Venus for the first time since Pioneer Venus (1978-1992), and for the first time ever in detail at polar latitudes. This article reviews some of our current knowledge from space and ground-based observations about the upper atmosph…