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Related papers: Refining the Oort and Galactic constants

200 papers

Using atomic hydrogen (HI) data from the VLA Galactic Plane Survey we measure the HI terminal velocity as a function of longitude for the first quadrant of the Milky Way. We use these data, together with our previous work on the fourth…

Astrophysics of Galaxies · Physics 2016-11-09 N. M. McClure-Griffiths , J. M. Dickey

Previous analyses of large databases of Milky Way stars have revealed the stellar disk of our Galaxy to be warped and that this imparts a strong signature on the kinematics of stars beyond the solar neighborhood. However, due to the…

We present rotation curves of the Galaxy based on the space-velocities of 197 OB stars and 144 classical cepheids, respectively, which range over a galactocentric distance interval of about 6 to 12 kpc. No significant differences between…

Astrophysics · Physics 2007-05-23 S. Frink , B. Fuchs , S. Roeser , R. Wielen

We have selected and analyzed a sample of OB stars with known line-of-sight velocities determined through ground-based observations and with trigonometric parallaxes and proper motions from the Gaia DR2 catalogue. Some of the stars in our…

Astrophysics of Galaxies · Physics 2018-09-28 V. V. Bobylev , A. T. Bajkova

An accurate knowledge of the dark matter distribution in the Milky Way is of crucial importance for galaxy formation studies and current searches for particle dark matter. In this paper we set new dynamical constraints on the Galactic dark…

Astrophysics of Galaxies · Physics 2015-12-03 Miguel Pato , Fabio Iocco , Gianfranco Bertone

We consider two previously studied samples of OB stars with different distance scales. The first one consists of 98 massive spectroscopic binary stars with photometric distances, and the second one consists on 140 OB stars with the…

Astrophysics of Galaxies · Physics 2017-03-22 V. V. Bobylev , A. T. Bajkova

A catalog of Cepheid variables is used to probe the kinematics of the Galactic disk. Radial velocities are measured for eight distant Cepheids toward l = 300; these new Cepheids provide a particularly good constraint on the distance to the…

Astrophysics · Physics 2009-10-30 Mark R. Metzger , John A. R. Caldwell , Paul L. Schechter

We present the results of the kinematic investigations carried out with the use of spatial velocities of red giants and sub-giants containing in the $Gaia$~EDR3 catalogue. The twelve kinematic parameters of the Ogorodnikov--Milne model have…

Astrophysics of Galaxies · Physics 2021-10-13 P. N. Fedorov , V. S. Akhmetov , A. B. Velichko , A. M. Dmytrenko , S. I. Denischenko

Our recent studies of axial-symmetry breaking in the nearby ($d <3 \,{\rm kpc}$) star counts are sensitive to the distortions of stellar orbits perpendicular and parallel to the orientation of the bar just within and beyond the outer…

Astrophysics of Galaxies · Physics 2020-08-20 Austin Hinkel , Susan Gardner , Brian Yanny

We present a sample of 254,882 luminous red giant branch (LRGB) stars selected from the APOGEE and LAMOST surveys. By combining photometric and astrometric information from the 2MASS and Gaia surveys, the precise distances of the sample…

Astrophysics of Galaxies · Physics 2023-04-12 Yuan Zhou , Xinyi Li , Yang Huang , Huawei Zhang

The nature of our Milky Way Galaxy is reexamined from an eclectic point of view. Evidence for a central bar, for example, is not reflected in the distribution of RR Lyrae variables in the central bulge [4,5], and it is not clear if either a…

Astrophysics of Galaxies · Physics 2015-06-17 David G. Turner

The distance to the Galactic center inferred from OGLE RR Lyrae variables observed in the direction of the bulge is Ro=8.1+-0.6 kpc. An accurate determination of Ro is hindered by countless effects that include an ambiguous extinction law,…

Astrophysics of Galaxies · Physics 2015-03-13 Daniel J. Majaess

A parameterized model of the mass distribution within the Milky Way is fitted to the available observational constraints. The most important single parameter is the ratio of the scale length R_d* of the stellar disk to R0. The disk and…

Astrophysics · Physics 2020-11-25 Walter Dehnen , James Binney

Here we statistically evaluate recent advances in determining the Sun-Galactic Center distance (Rsun) as well as recent measures of the orbital velocity around the Galactic Center (Vlsr), and the angular rotation parameters of various…

Astrophysics of Galaxies · Physics 2017-03-29 Jacques P Vallée

Predictions from a Galactic Structure and Kinematic model are compared to the absolute proper-motions of about 30,000 randomly selected stars with $9 < B_{\rm J} \le 19$ derived from the Southern Proper-Motion Program (SPM) toward the South…

We estimate the solar peculiar velocities and Oort constants using a sample of 5,627 A-type stars with $d<0.6\,\rm kpc$ and $|z|<0.1\,\rm kpc$, selected from the LAMOST surveys. The radial and tangential velocities of these A-type stars are…

Astrophysics of Galaxies · Physics 2021-03-31 F. Wang , H. -W. Zhang , Y. Huang , B. -Q. Chen , H. -F. Wang , C. Wang

We have tested the method of determining the solar Galactocentric distance R_0 and Galactic rotation velocity $V_0$ modified by Sofue et al. using near-solar-circle objects. The motion of objects relative to the local standard of rest has…

Astrophysics of Galaxies · Physics 2013-01-01 V. V. Bobylev

Recent numerical simulations have demonstrated that the Sun's dynamical history within the Milky Way may be much more complex than that suggested by its current low peculiar velocity. In particular, the Sun may have radially migrated…

Earth and Planetary Astrophysics · Physics 2011-08-09 Nathan A. Kaib , Rok Roškar , Thomas Quinn

Based on currently available data on the three-dimensional field of space velocities of young (<50 Myr) open star clusters and the radial velocities of HI clouds and star-forming (HII) regions, we have found the Galactic rotation curve in…

Astrophysics · Physics 2011-08-31 V. V. Bobylev , A. T. Bajkova , A. S. Stepanishchev

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