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Related papers: Local stellar kinematics from Hipparcos data

200 papers

The Pulkovo Compilation of Radial Velocities (PCRV) has been made to study the stellar kinematics in the local spiral arm. The PCRV contains weighted mean absolute radial velocities for 35 495 Hipparcos stars of various spectral types and…

Solar and Stellar Astrophysics · Physics 2016-06-29 George Gontcharov

We present I-band photometry, long-slit optical spectroscopy, and new aperture synthesis HI observations for eight late-type spirals with rotation velocities in the range 243 km/s < V_{rot} < 308 km/s. The sample will be used to study the…

Astrophysics · Physics 2008-11-26 K. Spekkens , R. Giovanelli

We show that the observed upper bound on the line-of-sight velocity dispersion of the stars in an early-type galaxy, sigma<400km/s, may have a simple dynamical origin within the LCDM cosmological model, under two main hypotheses. The first…

Astrophysics · Physics 2009-11-07 Abraham Loeb , P. J. E. Peebles

The Hypervelocity Star survey presents the currently largest sample of radial velocity measurements of halo stars out to 80 kpc. We apply spherical Jeans modeling to these data in order to derive the mass profile of the Galaxy. We restrict…

Astrophysics of Galaxies · Physics 2010-08-31 Oleg Y. Gnedin , Warren R. Brown , Margaret J. Geller , Scott J. Kenyon

This thesis develops a method for obtaining the star formation histories of a mixed, resolved population through the use of color-magnitude diagrams (CMDs). The method is applied to the derivation of the local star formation rate, modeling…

Astrophysics · Physics 2007-05-23 Michele Cignoni

We explore the phase-space structure of nearby halo stars identified kinematically from Gaia DR2 data. We focus on their distribution in velocity and in "integrals of motion" space as well as on their photometric properties. Our sample of…

Astrophysics of Galaxies · Physics 2018-06-27 Helmer H. Koppelman , Amina Helmi , Jovan Veljanoski

Traditionally runaway stars are O and B type stars with large peculiar velocities.We want to extend this definition to young stars (up to ~50 Myr) of any spectral type and identify those present in the Hipparcos catalogue applying different…

Astrophysics of Galaxies · Physics 2015-05-19 N. Tetzlaff , R. Neuhäuser , M. M. Hohle

We extract a sample of disc stars within 200 pc of the Sun from the RAVE and SDSS surveys. Distances are estimated photometrically and proper motions are from ground-based data. We show that the velocity-space substructure first revealed in…

Astrophysics of Galaxies · Physics 2015-05-27 Chang Hoon Hahn , J. A. Sellwood , Carlton Pryor

We use the proper motions (PM) of half a million red giant stars in Large Magellanic Cloud measured by Gaia to construct a 2d kinematic map of mean PM and its dispersion across the galaxy, out to 7 Kpc from its centre. We then explore a…

Astrophysics of Galaxies · Physics 2018-09-21 Eugene Vasiliev

We carry out a maximum-likelihood kinematic analysis of a sample of 1170 blue horizontal branch (BHB) stars from the Sloan Digital Sky Survey presented in Sirko et al. (2003) (Paper I). Monte Carlo simulations and resampling show that the…

We present a three dimensional velocity analysis of Milky Way disk kinematics using LAMOST K giant stars and the GPS1 proper motion catalogue. We find that Galactic disk stars near the anticenter direction (in the range of Galactocentric…

Astrophysics of Galaxies · Physics 2018-04-03 Haifeng Wang , Martín López-Corredoira , Jeffrey L. Carlin , Licai Deng

The kinematics of satellite galaxies reflect the masses of the extended dark matter haloes in which they orbit, and thus shed light on the mass-luminosity relation (MLR) of their corresponding central galaxies. In this paper we select a…

Astrophysics · Physics 2009-11-19 Surhud More , Frank C. van den Bosch , Marcello Cacciato , Houjun Mo , Xiaohu Yang , Ran Li

We have selected a sample of 326 young $(\log t<8)$ open star clusters with the proper motions and distances calculated by various authors from Gaia DR2 data. The mean values of their line-of-sight velocities have also been taken from…

Astrophysics of Galaxies · Physics 2019-03-25 V. V. Bobylev , A. T. Bajkova

We present rotation curves for 19, mostly luminous, early-type disk galaxies. Rotation velocities are measured from a combination of HI velocity fields and long-slit optical emission line spectra along the major axis. We find that the…

Astrophysics · Physics 2008-11-26 E. Noordermeer , J. M. van der Hulst , R. Sancisi , R. S. Swaters , T. S. van Albada

The well-known discrepancy in galactic rotation curves refers to the mismatch between observed rotational velocities and the velocities predicted by baryonic matter. In this study we investigate a potential pattern in the discrepancy, which…

Astrophysics of Galaxies · Physics 2026-01-09 Tomer Zimmerman , Lev Tal-Or , Roy Gomel

In recent years surveys have identified several dozen B stars in the Milky Way halo moving faster than the local escape speed. The origin of most of these hypervelocity stars (HVSs) is still poorly constrained. Here we show that the…

Astrophysics of Galaxies · Physics 2023-01-02 Aleksey Generozov , Hagai B. Perets

Be stars are rapid rotators surrounded by a gaseous disk envelope whose origin is still under debate. This envelope is responsible for observed emission lines and large infrared excess. To progress in the understanding of the physical…

Solar and Stellar Astrophysics · Physics 2019-01-16 Y. R. Cochetti , C. Arcos , S. Kanaan , A. Meilland , L. S. Cidale , M. Curé

Gaia DR2 has delivered full-sky 6-D measurements for millions of stars, and the quest to understand the dynamics of our Galaxy has entered a new phase. Our aim is to reveal and characterize the kinematic sub-structure of the different…

Astrophysics of Galaxies · Physics 2018-11-14 P. Ramos , T. Antoja , F. Figueras

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 full modeling of tangent point emission of HI as seen in the 21 cm transition in the inner Galaxy ($R \simeq 3-8 \kpc$). The model used takes into account emission from a large path length along the line of sight, corresponding…

Astrophysics · Physics 2011-03-28 Sangeeta Malhotra