Search Publications
Distances to Galactic X-ray binaries with Gaia DR2
Barmby, P.; Bahramian, A.; Arnason, R. M. +2 more
Precise and accurate measurements of distances to Galactic X-ray binaries (XRBs) reduce uncertainties in the determination of XRB physical parameters. We have cross-matched the XRB catalogues of Liu, van Paradijs & van den Heuvel to the results of Gaia Data Release 2. We identify 86 XRBs with a Gaia candidate counterpart, of which 32 are low-m…
The White Dwarf Binary Pathways Survey - IV. Three close white dwarf binaries with G-type secondary stars
Gänsicke, B. T.; Rebassa-Mansergas, A.; Raddi, R. +12 more
Constraints from surveys of post-common envelope binaries (PCEBs) consisting of a white dwarf plus an M-dwarf companion have led to significant progress in our understanding of the formation of close white dwarf binary stars with low-mass companions. The white dwarf binary pathways project aims at extending these previous surveys to larger seconda…
A multiband map of the natural night sky brightness including Gaia and Hipparcos integrated starlight
Masana, Eduard; Carrasco, Josep Manel; Bará, Salvador +1 more
The natural night sky brightness is a relevant input for monitoring the light pollution evolution at observatory sites, by subtracting it from the overall sky brightness determined by direct measurements. It is also instrumental for assessing the expected darkness of the pristine night skies. The natural brightness of the night sky is determined b…
Optimized modelling of Gaia-Hipparcos astrometry for the detection of the smallest cold Jupiter and confirmation of seven low-mass companions
Butler, R. Paul; Vogt, Steven S.; Oppenheimer, Rebecca +6 more
To fully constrain the orbits of low-mass circumstellar companions, we conduct combined analyses of the radial velocity data and the Gaia and Hipparcos astrometric data for eight nearby systems. Our study shows that companion-induced position and proper motion differences between Gaia and Hipparcos are significant enough to constrain orbits of low…
Searching for new solar twins: The Inti survey for the Northern Sky
Meléndez, Jorge; Reggiani, Henrique; Schlaufman, Kevin C. +9 more
Solar twins are key in different areas of astrophysics, however only just over a hundred were identified and well-studied in the last two decades. In this work, we take advantage of the very precise Gaia (DR2/EDR3), Tycho, and 2MASS photometric systems to create the ${{Inti}}$ survey of new solar twins in the Northern Hemisphere. The spectra of ou…
Absolute parameters of young stars: V puppis
Blackford, M. G.; Budding, E.; Banks, T. +2 more
New spectrometric data on V Pup are combined with satellite photometry [HIPPARCOS and recent Transiting Exoplanet Survey Satellite (TESS)] to allow a revision of the absolute parameters with increased precision. We find: M1 = 14.0 ± 0.5, M2 = 7.3 ± 0.3 (M⊙); R1 = 5.48 ± 0.18, R2 = 4.59 ± 0.15 …
Explosive nucleosynthesis of a metal-deficient star as the source of a distinct odd-even effect in the solar twin HIP 11915
Meléndez, Jorge; Karakas, Amanda I.; Asplund, Martin +2 more
The abundance patterns observed in the Sun and in metal-poor stars show a clear odd-even effect. An important question is whether the odd-even effect in solar-metallicity stars is similar to the Sun, or if there are variations that can tell us about different chemical enrichment histories. In this work, we report for the first time observational e…
Magnetic chemically peculiar stars investigated by the Solar Mass Ejection Imager
Paunzen, E.; Prišegen, M.; Bernhard, K. +2 more
Since the discovery of the spectral peculiarities of their prototype α2 Canum Venaticorum in 1897, the so-called ACV variables, which are comprised of several groups of chemically peculiar stars of the upper main sequence, have been the target of numerous photometric and spectroscopic studies. Especially for the brighter ACV variables, …
A celestial matryoshka: dynamical and spectroscopic analysis of the Albireo system
Drimmel, Ronald; Bastian, Ulrich; Sozzetti, Alessandro +4 more
We present a spectroscopic characterization and a new orbital solution for the binary system β Cyg Aa/Ac (MCA 55), the primary component ( β Cyg A) of the well-known wide double star Albireo. By matching evolutionary tracks to the physical parameters of all three Albireo stars ( β Cyg Aa, Ac, and B) as obtained from a spectroscopic analysis of TIG…
BRITE observations of ν Centauri and γ Lupi, the first non-eclipsing members of the new class of nascent binaries
Handler, G.; Wade, G. A.; Pigulski, A. +8 more
Results of an analysis of the BRITE-Constellation and Solar Mass Ejection Imager photometry and radial-velocity observations, archival and new, of two single-lined spectroscopic binary (SB) systems ν Centauri and γ Lupi are reported. In the case of γ Lup AB, a visual binary, an examination of the light-time effect shows that component A is the SB.…