English

Cepheid Kinematics and the Galactic Warp

Astrophysics of Galaxies 2013-10-29 v1

Abstract

The space velocities of 200 long-period (P>5P>5 days) classical Cepheids with known proper motions and line-of-sight velocities whose distances were estimated from the period--luminosity relation have been analyzed. The linear Ogorodnikov-Milne model has been applied, with the Galactic rotation having been excluded from the observed velocities in advance. Two significant gradients have been found in the Cepheid velocities, W/Y=2.1±0.7\partial W/\partial Y=-2.1\pm0.7 km s1^{-1} kpc1^{-1} and V/Z=27±10\partial V/\partial Z= 27\pm10 km s1^{-1} kpc1^{-1}. In such a case, the angular velocity of solid-body rotation around the Galactic XX axis directed to the Galactic center is 15±5-15\pm5 km s1^{-1} kpc1^{-1}.

Keywords

Cite

@article{arxiv.1310.7187,
  title  = {Cepheid Kinematics and the Galactic Warp},
  author = {Vadim Bobylev},
  journal= {arXiv preprint arXiv:1310.7187},
  year   = {2013}
}

Comments

9 pages, 3 figures, 1 table

R2 v1 2026-06-22T01:54:49.746Z