The Young Open Cluster Berkeley 55
Abstract
We present UBV photometry of the highly reddened and poorly studied open cluster Berkeley 55, revealing an important population of B-type stars and several evolved stars of high luminosity. Intermediate-resolution far-red spectra of several candidate members confirm the presence of one F-type supergiant and six late supergiants or bright giants. The brightest blue stars are mid-B giants. Spectroscopic and photometric analyses indicate an age 50 ± 10 Myr. The cluster is located at a distance d ≈ 4 kpc, consistent with other tracers of the Perseus Arm in this direction. Berkeley 55 is thus a moderately young open cluster with a sizable population of candidate red (super)giant members, which can provide valuable information about the evolution of intermediate-mass stars.
Partially based on observations collected at the Nordic Optical Telescope and the William Herschel Telescope (La Palma).- Publication:
-
The Astronomical Journal
- Pub Date:
- February 2012
- DOI:
- 10.1088/0004-6256/143/2/46
- arXiv:
- arXiv:1112.0414
- Bibcode:
- 2012AJ....143...46N
- Keywords:
-
- Galaxy: structure;
- open clusters and associations: individual: Berkeley 55;
- stars: early-type;
- stars: evolution;
- supergiants;
- Astrophysics - Galaxy Astrophysics;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- Accepted for publication in the Astronomical Journal. Tables 3, 6 and 7 are published electronically, and only the first few rows are shown here