A search for stars physically associated with the 16-day Cepheid X Cygni. I. Luminous Stars in the field.
Abstract
UBV photometry and MK spectral types are presented for luminous stars which lie within 2 1/2° of the 16d Cepheid X Cyg. Portions of two distant associations are detected, at distances of 1.78 ± 0.15 kpc and 4.80 ± 0.29 kpc, respectively. The nearer group contains stars lying close to the main sequence with ages of ≡4.5×106 yr, and is believed to represent an extension below the galactic plane of the youthful Cyg OB1 association. The more distant group is sparser and older, with an age of ≡4×107 yr. It is argued that X Cyg is unlikely to be a member of either association.
- Publication:
-
The Astronomical Journal
- Pub Date:
- May 1983
- DOI:
- 10.1086/113353
- Bibcode:
- 1983AJ.....88..650T
- Keywords:
-
- Astronomical Photometry;
- Cepheid Variables;
- Stellar Luminosity;
- Ubv Spectra;
- Electrophotometry;
- Interstellar Extinction;
- Stellar Color;
- Astronomy