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Related papers: The uncertainty in Galactic parameters

200 papers

We present a new, detailed, analysis of the spatial distribution of Galactic HII regions, exploiting a far richer database than used in previous analyses. Galactocentric distances have been derived for 550 objects. Distances from the Sun…

Astrophysics · Physics 2009-11-10 R. Paladini , G. DeZotti , R. D. Davies

We determine the Galactic potential in the solar neigbourhood from RAVE observations. We select red clump stars for which accurate distances, radial velocities, and metallicities have been measured. Combined with data from the 2MASS and…

The Sun's vertical displacement from the galactic plane is determined model-independently from 3457 spectroscopic-parallax distance estimates for 2397 OB stars within 1200 pc of the Sun. The result, 19.5 +/- 2.2 pc, agrees well with other…

Astrophysics · Physics 2007-05-23 B. Cameron Reed

We analyse the radial and tangential velocity fields in the Galaxy as seen from the Sun by using as a first approximation a simple axisymmetric model, which we then compare with the corresponding fields in a barred N-body model of the Milky…

Astrophysics of Galaxies · Physics 2015-05-14 Maura Brunetti , Daniel Pfenniger

A new approach to determining the solar galactocentric distance, $R_0$, from the geometry of spiral-arm segments is proposed. Geometric aspects of the problem are analyzed and a simplified three-point method for estimating $R_0$ from…

Astrophysics of Galaxies · Physics 2018-03-14 I. I. Nikiforov , A. V. Veselova

We report the first determination of the distance to the Galactic centre based on the kinematics of halo objects. We apply the statistical-parallax technique to the sample of ~2500 Blue Horizontal Branch (BHB) stars compiled by Xue et al.…

Astrophysics of Galaxies · Physics 2020-09-17 N. D. Utkin , A. K. Dambis

We transformed radial velocities compiled from more than 1400 published sources, including the Geneva--Copenhagen survey of the solar neighborhood (CORAVEL-CfA), into a uniform system based on the radial velocities of 854 standard stars in…

Astrophysics · Physics 2019-10-25 Vadim V. Bobylev , George A. Gontcharov , Anisa T. Bajkova

We study the peculiar velocity field inferred from the Mark III spirals using a new method of analysis. We estimate optimal values of Tully-Fisher scatter and zero-point offset, and we derive the 3-dimensional rms peculiar velocity…

Astrophysics · Physics 2009-10-31 Nelson Padilla , Diego G. Lambas

Using data from the literature, we made a list of individual estimates of the solar Galactocentric distance, which were performed after 2017 by different methods. These values have not yet been used to calculate the best value of mean…

Astrophysics of Galaxies · Physics 2021-05-19 V. V. Bobylev , A. T. Bajkova

The kinematic properties of young stars that have not yet reached the stage of the main sequence are studied. The selection of these stars was recently carried out by Marton et al. (2019) and Vioque et al. (2020) according to the Gaia DR2…

Astrophysics of Galaxies · Physics 2020-09-02 V. V. Bobylev , A. T. Bajkova

The young star velocity field is analysed by means of a galactic model which takes into account solar motion, differential galactic rotation and spiral arm kinematics. We use two samples of Hipparcos data, one containing O- and B-type stars…

Astrophysics · Physics 2009-11-06 D. Fernandez , F. Figueras , J. Torra

We report a new analysis of stellar dynamics in the Galactic centre, based on improved sky and LOS velocities for >100 stars within a few arcsec of SgrA*. Overall the motions do not deviate strongly from isotropy. For 32 stars with all 3…

Astrophysics · Physics 2009-10-31 R. Genzel , C. Pichon , A. Eckart , O. E. Gerhard , T. Ott

The kinematic parameters identified from high-velocity stars situated within 100 kpc are examined and analyzed. We included three high velocity programs comprising 591, 87, and 519 stars as a function of distances ranging from 0.10 to…

Solar and Stellar Astrophysics · Physics 2025-01-23 W. H. Elsanhoury

We examine the inner profiles of the rotation curves of galaxies in the velocity range from dwarf galaxies to Milky-way like galaxies, having maximum of rotation, $V_{\rm max}$, in the range [30-250] km/s, whose diversity is much larger…

Astrophysics of Galaxies · Physics 2024-10-11 A. Del Popolo , M. Le Delliou

The solar tachocline, located at the interface between the latitude-dependent rotation of the convection zone and the rigid radiative interior, presents high gradients of angular velocity which are of particular interest for the models of…

Astrophysics · Physics 2013-08-01 T. Corbard , S. J. Jiménez-Reyes , S. Tomczyk , M. Dikpati , P. Gilman

With the help of Gaia DR2, we are able to obtain the full 6-D phase space information for stars from LAMOST DR5. With high precision of position, velocity, and metallicity, the rotation of the local stellar halo is presented using the K…

Astrophysics of Galaxies · Physics 2019-02-14 Hao Tian , Chao Liu , Yan Xu , Xiangxiang Xue

The paper investigates the question of whether or not determinations of the distance between the Sun and the Galactic center R0 are affected by the so-called "bandwagon effect", leading to selection effects in published data that tend to be…

Astrophysics of Galaxies · Physics 2013-01-30 Zinovy Malkin

Rotational and radial velocities have been measured for 1589 evolved stars of spectral types F, G and K and luminosity classes IV, III, II and Ib, based on observations carried out with the CORAVEL spectrometers. The precision in radial…

Solar and Stellar Astrophysics · Physics 2013-12-20 J. R. De Medeiros , S. Alves , S. Udry , J. Andersen , B. Nordström , M. Mayor

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