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Related papers: Velocity-space substructure from nearby RAVE and S…

200 papers

To better understand our Galaxy, we investigate the pertinency of describing the sys tem of nearby disk stars in terms of a two-components Schwarzschild velocity distributio n.Using the proper motion and parallax information of Hipparcos…

Astrophysics · Physics 2009-11-13 R. E. de Souza , R. Teixeira

(Abridged) Aims:We develop a method for deriving distances from spectroscopic data and obtaining full 6D phase-space coordinates for the RAVE survey's second data release. Methods: We used stellar models combined with atmospheric properties…

A Bayesian approach to the determination of stellar distances from photometric and spectroscopic data is presented and tested both on pseudodata, designed to mimic data for stars observed by the RAVE survey, and on the real stars from the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Benedict Burnett , James Binney

We discuss our targeted search for hypervelocity stars (HVSs), stars traveling with velocities so extreme that dynamical ejection from a massive black hole is their only suggested origin. Our survey, now half complete, has successfully…

Astrophysics · Physics 2008-11-26 Warren R. Brown , Margaret J. Geller , Scott J. Kenyon , Michael J. Kurtz

Context. Hypervelocity stars move fast enough to leave the gravitational field of their home galaxies and venture into intergalactic space. The most extreme examples known have estimated speeds in excess of 1000 km/s. These can be easily…

Astrophysics of Galaxies · Physics 2019-07-09 R. de la Fuente Marcos , C. de la Fuente Marcos

We present a kinematic analysis of the Small Magellanic Cloud using 3700 spectra extracted from the European Southern Observatory archive. We used data from Gaia and near-infrared photometry to select stellar populations and discard…

We present three-dimensional space velocities of stars selected to be consistent with membership in the Virgo stellar substructure. Candidates were selected from SA 103, a single 40x40 arcmin field from our proper motion (PM) survey in…

Using the cross-matched data of Gaia EDR3 and the 2MASS Point Source Catalog, a sample of RC stars with parallax accuracies better than 20% is identified and used to reveal the nearby spiral pattern traced by old stars. As shown in the…

Astrophysics of Galaxies · Physics 2022-06-01 Zehao Lin , Ye Xu , Ligang Hou , Dejian Liu , Yingjie Li , Chaojie Hao , Jingjing Li , Shuaibo Bian

Detection of bending waves is a highly challenging task even in nearby disc galaxies due to their sub-kpc bending amplitudes. However, simulations show that the harmonic bending of a Milky Way like disc galaxy is associated with a harmonic…

Astrophysics of Galaxies · Physics 2022-04-20 Meera Nandakumar , Chaitra Narayan , Prasun Dutta

We investigate radial and vertical metallicity gradients for a sample of red clump stars from the RAdial Velocity Experiment (RAVE) Data Release 3. We select a total of 6781 stars, using a selection of colour, surface gravity and…

Astrophysics of Galaxies · Physics 2015-06-03 S. Bilir , S. Karaali , S. Ak , O. Onal , N. D. Dagtekin , T. Yontan , G. Gilmore , G. M. Seabroke

We reexamine the SIMBAD database with incorporated Gaia DR3 parallaxes and proper motions. Appropriate query searches allow us to find several nearby stars with measured radial velocities having flybies within 1 ly from the Sun (in linear…

Solar and Stellar Astrophysics · Physics 2024-02-21 Igor Yu. Potemine

The variations of kinematic parameters with age are considered for a sample of 15 402 thin-disk O--F stars with accurate $\alpha$, $\delta$, $\mu$, and $\pi>3$ mas from the Hipparcos catalogue and radial velocities from the PCRV catalogue.…

Solar and Stellar Astrophysics · Physics 2019-10-25 George Gontcharov

We have searched for in-falling stellar streams on to the local Milky Way disc in the CORAVEL and RAVE surveys. The CORAVEL survey consists of local dwarf stars (Nordstrom et al. Geneva-Copenhagen survey) and local Famaey et al. giant…

We consider the process of stellar binaries tidally disrupted by a supermassive black hole. For highly eccentric orbits, as one star is ejected from the three-body system, the companion remains bound to the black hole. Hypervelocity stars…

Astrophysics of Galaxies · Physics 2015-06-16 Elena M. Rossi , Shiho Kobayashi , Re'em Sari

By taking advantage of the superb measurements of position and velocity for an unprecedented large number of stars provided in Gaia DR2, we have generated the first maps of the rotation velocity, $V_{\rm rot}$, and vertical velocity,…

Astrophysics of Galaxies · Physics 2018-06-27 Daisuke Kawata , Junichi Baba , Ioana Ciucă , Mark Cropper , Robert J. J. Grand , Jason A. S. Hunt , George Seabroke

We present the second data release of the Radial Velocity Experiment (RAVE), an ambitious spectroscopic survey to measure radial velocities (RVs) and stellar atmosphere parameters of up to one million stars using the 6dF multi-object…

The second data release from ESA's Gaia mission has revealed many ridge-like structures in the velocity distribution of the Milky Way. We show that these can arise naturally from winding transient spiral structure that is commonly seen in…

Astrophysics of Galaxies · Physics 2018-09-26 Jason A. S. Hunt , Jack Hong , Jo Bovy , Daisuke Kawata , Robert J. J. Grand

We have analyzed the catalog of 2106 non-kinematically selected metal poor stars in the solar neighborhood published by Beers et al. (2000), with the goal of quantifying the amount of substructure in the motions of the fastest halo stars.…

Astrophysics · Physics 2007-05-23 P. ReFiorentin , A. Helmi , M. G. Lattanzi , A. Spagna

We test the performance of the semi-analytic self-consistent Just-Jahrei{\ss} disc model (JJ model) with the astrometric data from the Tycho-Gaia Astrometric Solution (TGAS) sub-catalogue of the first Gaia data release (Gaia DR1), as well…

Our main aim is to test the non-variability of the radial velocity (RV) of a sample of 2351 standard stars used for wavelength calibration of the RVS instrument onboard Gaia. In this paper, we present the spectroscopic analysis of these…

Solar and Stellar Astrophysics · Physics 2022-09-28 A. Boulkaboul , Y. Damerdji , T. Morel , Y. Frémat , C. Soubiran , E. Gosset , T. E. Abdelatif