Search Publications
Validation of the new Hipparcos reduction
van Leeuwen, F.
Context: A new reduction of the astrometric data as produced by the Hipparcos mission has been published, claiming accuracies for nearly all stars brighter than magnitude Hp=8 to be better, by up to a factor 4, than in the original catalogue.
Aims: The new Hipparcos astrometric catalogue is checked for the quality of the data and the consisten…
The reversal of the star formation-density relation in the distant universe
Daddi, E.; Elbaz, D.; Popesso, P. +11 more
Aims:We study the relationship between the local environment of galaxies and their star formation rate (SFR) in the Great Observatories Origins Deep Survey, GOODS, at z∼1.
Methods: We use ultradeep imaging at 24 µm with the MIPS camera onboard {Spitzer} to determine the contribution of obscured light to the SFR of galaxies over the redsh…
The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
Gilli, R.; Comastri, A.; Hasinger, G.
We present a detailed and self-consistent modeling of the cosmic X-ray background (XRB) based on the most up-to-date X-ray luminosity functions (XLF) and evolution of Active Galactic Nuclei (AGN). The large body of observational results collected by soft (0.5-2 keV) and hard (2-10 keV) X-ray surveys are used to constrain at best the properties of …
The Geneva-Copenhagen survey of the Solar neighbourhood II. New uvby calibrations and rediscussion of stellar ages, the G dwarf problem, age-metallicity diagram, and heating mechanisms of the disk
Holmberg, J.; Nordström, B.; Andersen, J.
Context: Ages, metallicities, space velocities, and Galactic orbits of stars in the Solar neighbourhood are fundamental observational constraints on models of galactic disk evolution. Understanding and minimising systematic errors and sample selection biases in the data is crucial for their interpretation.
Aims: We aim to consolidate the calib…
The XMM-Newton extended survey of the Taurus molecular cloud (XEST)
Audard, M.; Güdel, M.; Grosso, N. +18 more
Context: The Taurus Molecular Cloud (TMC) is the nearest large star-forming region, prototypical for the distributed mode of low-mass star formation. Pre-main sequence stars are luminous X-ray sources, probably mostly owing to magnetic energy release.
Aims: The XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST) presented in this p…
Reconstruction of solar total irradiance since 1700 from the surface magnetic flux
Solanki, S. K.; Krivova, N. A.; Balmaceda, L.
Context: Total solar irradiance changes by about 0.1% between solar activity maximum and minimum. Accurate measurements of this quantity are only available since 1978 and do not provide information on longer-term secular trends.
Aims: In order to reliably evaluate the Sun's role in recent global climate change, longer time series are, however,…
The representative XMM-Newton cluster structure survey (REXCESS) of an X-ray luminosity selected galaxy cluster sample
Zhang, Y. -Y.; Finoguenov, A.; Böhringer, H. +31 more
Context: The largest uncertainty for cosmological studies using clusters of galaxies is introduced by our limited knowledge of the statistics of galaxy cluster structure, and of the scaling relations between observables and cluster mass.
Aims: To improve on this situation we have started an XMM-Newton Large Programme for the in-depth study of …
Temperature profiles of a representative sample of nearby X-ray galaxy clusters
Finoguenov, A.; Böhringer, H.; Arnaud, M. +4 more
Context: A study of the structural and scaling properties of the temperature distribution of the hot, X-ray emitting intra-cluster medium of galaxy clusters, and its dependence on dynamical state, can give insights into the physical processes governing the formation and evolution of structure.
Aims: Accurate temperature measurements are a pre-…
Hubble Space Telescope time-series photometry of the planetary transit of HD 189733: no moon, no rings, starspots
Bouchy, F.; Moutou, C.; Pont, F. +7 more
We monitored three transits of the giant gas planet around the nearby K dwarf HD 189733 with the ACS camera on the Hubble Space Telescope. The resulting very-high accuracy lightcurve (signal-to-noise ratio near 15 000 on individual measurements, 35 000 on 10-min averages) allows a direct geometric measurement of the orbital inclination, radius rat…
A new calibration of Galactic Cepheid period-luminosity relations from B to K bands, and a comparison to LMC relations
Arriagada, P.; McArthur, B. E.; Benedict, G. F. +8 more
Context: The universality of the Cepheid period-luminosity (PL) relations has been under discussion since metallicity effects were assumed to play a role in the value of the intercept and, more recently, of the slope of these relations.
Aims: The goal of the present study is to calibrate the Galactic PL relations in various photometric bands (…