Keplerian rotation of our galaxy?
Piotr Gnaciński , Tomasz Młynik
AbstractIt is common to attribute a flat rotation curve to our Galaxy. However, in a recent paper, Galazutdinov et al. obtained a Keplerian rotation curve for interstellar clouds in the outer parts of the Galaxy. They calculated the distances from equivalent widths of interstellar CaII lines. The radial velocity was also measured on the interstellar CaII absorption line. We verify the results of Galazutdinov et al. based on observations of old open clusters. We propose that the observations of flat and Keplerian rotation curves may be caused by the assumption of circular orbits. The application of formulas derived with the assumption of circular orbits to elliptical ones may mimics the flat rotation curve. The interstellar clouds with cross-sections larger than stars may have almost circular orbits, and the derived rotation curve will be Keplerian.
|Other language title versions|
|Journal series||Publications of the Astronomical Society of the Pacific, ISSN 0004-6280|
|Publication size in sheets||0.5|
|Keywords in English||galaxy, kinematics and dynamics - cosmology, dark matter|
|Score|| = 30.0, 20-12-2017, ArticleFromJournal|
= 35.0, 20-12-2017, ArticleFromJournal
|Publication indicators||: 2016 = 4.446 (2) - 2016=4.327 (5)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.