相关论文: Selection of the SIM Astrometric Grid

[abridged] In this work we study in detail the kinematics of tidal debris stars to investigate the implications of the new scenario that the observed sample of Hypervelocity stars could partly originate from a dwarf-host galaxy collision.…

We employ measurements of the [alpha/Fe] ratio derived from low-resolution (R~2000) spectra of 17,277 G-type dwarfs from the SEGUE survey to separate them into likely thin- and thick-disk subsamples. Both subsamples exhibit strong gradients…

Using several realisations of the Galactic population of close white dwarf binaries, we have explored the selection bias for resolved binaries in the LISA data stream. We have assumed a data analysis routine that is capable of identifying…

We have computed a grid of high resolution synthetic spectra for cool stars (2500<Teff<6000 K) in the wavelength range 6000 -- 10200A, by employing an updated line list of atomic and molecular lines, together with state-of-the-art model…

Gaia-DR2 has provided an unprecedented number of white dwarf candidates of our Galaxy. In particular, it is estimated that Gaia-DR2 has observed nearly 400,000 of these objects and close to 18,000 up to 100 pc from the Sun. This large…

ABRIDGED: METHODS: We have conducted a high-resolution spectroscopic study of 714 F and G dwarf and subgiant stars in the Solar neighbourhood. The star sample has been kinematically selected to trace the Galactic thin and thick disks to…

The launching of up to four astrometric missions in the next decade will enable us to make measurements of stars in tidal streamers from Galactic satellites of sufficient accuracy to place strong constraints on the mass distribution in the…

This paper is the second one in a series devoted to the study of properties of binaries involving M giants. The binary frequency of field M giants is derived and compared with the binary fraction of K giants. Diagrams of the CORAVEL…

We estimate the fraction of F,G,K stars with close binary companions by analysing multi-epoch stellar spectra from SDSS and LAMOST for radial velocity (RV) variations. We employ a Bayesian method to infer the maximum likelihood of the…

In searches for planetary transits in the field, well over half of the survey stars are typically giants or other stars that are too large to permit straightforward detection of planets. For all-sky searches of bright V<~11 stars, the…

Galaxy evolution by interaction driven transformation is probably highly efficient in groups of galaxies. Dwarf galaxies with their shallow potential are expected to reflect the interaction most prominently in their observable structure.…

We investigated almost 500 stars distributed among 193 binary or multiple systems made of late-F, G-, or early-K primaries and late-K or M dwarf companion candidates. For all of them, we compiled or measured coordinates, J-band magnitudes,…

The study of Stark broadening of neutral helium lines, despite significant advances over recent decades, has not led to updated large grids of helium line profiles relevant to the spectroscopic study of helium-rich stars. While the…

Hipparcos astrometric binaries were observed with the NICI adaptive optics system at Gemini-S, completing the work of Paper I (Tokovinin et al. 2012). Among the 65 F, G, K dwarfs within 67pc of the Sun studied here, we resolve 18 new…

We report on abundances of O, Mg, Si, Ca and Fe for 10 giants in the Sgr dwarf spheroidal derived from high resolution spectra obtained with UVES at the 8.2m Kueyen-VLT telescope. The iron abundance spans the range -0.8 <[Fe/H] < 0.0 and…

We present criteria for the photometric selection of M-dwarfs using all-sky photometry, with a view to identifying M-dwarf candidates for inclusion in the input catalogues of upcoming all-sky surveys, including TESS and FunnelWeb. The…

We present a cadence optimization strategy to unveil a large population of kilonovae using optical imaging alone. These transients are generated during binary neutron star and potentially neutron star-black hole mergers and are…

As part of a comprehensive effort to characterize the nearest stars, the CHIRON echelle spectrograph on the CTIO/SMARTS 1.5m telescope is being used to acquire high resolution (R = 80000) spectra of K dwarfs within 50 parsecs. This paper…

The third data release of Gaia was the first to include orbital solutions assuming non-single stars. Here, we apply the astrometric triage technique of Shahaf et al. to identify binary star systems with companions that are not single…

We use LAMOST DR4 M giants combined with Gaia DR2 proper motions and ALLWISE photometry to obtain an extremely pure sample of Sagittarius (Sgr) stream stars. Using TiO5 and CaH spectral indices as an indicator, we selected out a large…