Search Publications
Black hole, neutron star and white dwarf candidates from microlensing with OGLE-III
Soszyński, I.; Udalski, A.; Szymański, M. K. +13 more
Most stellar remnants so far have been found in binary systems, where they interact with matter from their companions. Isolated neutron stars and black holes are difficult to find as they are dark, yet they are predicted to exist in our Galaxy in vast numbers. We explored the OGLE-III data base of 150 million objects observed in years 2001-2009 an…
Studying the evolution of AGB stars in the Gaia epoch
Di Criscienzo, M.; Dell'Agli, F.; Ventura, P. +6 more
We present asymptotic giant branch (AGB) models of solar metallicity, to allow the interpretation of observations of Galactic AGB stars, whose distances should be soon available after the first release of the Gaia catalogue. We find an abrupt change in the AGB physical and chemical properties, occurring at the threshold mass to ignite hot bottom b…
The evolution of the Sun's birth cluster and the search for the solar siblings with Gaia
Brown, A. G. A.; Antoja, T.; Portegies Zwart, S. +3 more
We use self-consistent numerical simulations of the evolution and disruption of the Sun's birth cluster in the Milky Way potential to investigate the present-day phase-space distribution of the Sun's siblings. The simulations include the gravitational N-body forces within the cluster and the effects of stellar evolution on the cluster population. …
The Gaia spectrophotometric standard stars survey - III. Short-term variability monitoring
Jordi, C.; Figueras, F.; Marinoni, S. +14 more
We present the results of the short-term constancy monitoring of candidate Gaia Spectrophotometric Standard Stars (SPSS). We obtained time series of typically 1.24 h - with sampling periods from 1-3 min to a few hours, depending on the case - to monitor the constancy of our candidate SPSS down to 10 mmag, as required for the calibration of Gaia ph…
Masses of the components of SB2s observed with Gaia - II. Masses derived from PIONIER interferometric observations for Gaia validation
Mazeh, T.; Grellmann, R.; Tal-Or, L. +15 more
In anticipation of the Gaia astrometric mission, a sample of spectroscopic binaries is being observed since 2010 with the Spectrograph pour l'Observation des PHénomènes des Intérieurs stellaires et des Exoplanètes (SOPHIE) spectrograph at the Haute-Provence Observatory. Our aim is to derive the orbital elements of double-lined spectroscopic binari…
Masses of the components of SB2 binaries observed with Gaia - III. Accurate SB2 orbits for 10 binaries and masses of HIP 87895
Mazeh, T.; Tal-Or, L.; Halbwachs, J. -L. +9 more
In anticipation of the Gaia astrometric mission, a large sample of spectroscopic binaries has been observed since 2010 with the Spectrographe pour l'Observation des PHénomènes des Intérieurs Stellaires et des Exoplanètes spectrograph at the Haute-Provence Observatory. Our aim is to derive the orbital elements of double-lined spectroscopic binaries…
Using radio stars to link the Gaia and VLBI reference frames
Malkin, Zinovy
A possible method for linking the optical Gaia Celestial Reference Frame (GCRF) to the VLBI-based International Celestial Reference Frame (ICRF) is to use radio stars in a manner similar to that in the linking of the Hipparcos Celestial Reference Frame (HCRF) to ICRF. In this work, an obtainable accuracy of the orientation angles between GCRF and …
Gaia transient detection efficiency: hunting for nuclear transients
Harrison, D. L.; Walton, N. A.; Wyrzykowski, Ł. +5 more
We present a study of the detectability of transient events associated with galaxies for the Gaia European Space Agency astrometric mission. We simulated the on-board detections, and on-ground processing for a mock galaxy catalogue to establish the properties required for the discovery of transient events by Gaia, specifically tidal disruption eve…