Classical Cepheids and the spiral structure of the Milky Way
Astrophysics of Galaxies
2015-09-23 v1 Solar and Stellar Astrophysics
Abstract
We use the currently most complete collection of reliable Cepheid positions (565 stars) out to ~5 kpc based mostly on our photometric data to outline the spiral pattern of our Galaxy. We find the pitch-angle to be equal to 9--10 degrees with the most accurate estimate (i=9.5 +/-0.1 degrees) obtained assuming that the spiral pattern has a four-armed structure, and the solar phase angle in the spiral pattern to be chi_0 = 121+/-3 degrees. The pattern speed is found to be Omega_P=25.2+/-0.5km/s/kpc based on a comparison of the positions of the spiral arms delineated by Cepheids and maser sources and the age difference between these objects.
Cite
@article{arxiv.1505.01782,
title = {Classical Cepheids and the spiral structure of the Milky Way},
author = {A. K. Dambis and L. N. Berdnikov and Yu. N. Efremov and A. Yu. Kniazev and A. S. Rastorguev and E. V. Glushkova and V. V. Kravtsov and D. G. Turner and D. J. Majaess and R. Sefako},
journal= {arXiv preprint arXiv:1505.01782},
year = {2015}
}
Comments
21 pages, 11 figures. To appear in Astronomy Letters