Galactic clusters with associated Cepheid variables. VII. Berkeley 58 and CG Cassiopeiae

Autor: Turner, David G., Forbes, D., English, D., Leonard, P. J. T., Scrimger, J. N., Wehlau, A. W., Phelps, R. L., Berdnikov, L. N., Pastukhova, E. N.
Rok vydání: 2008
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1111/j.1365-2966.2008.13413.x
Popis: Photoelectric, photographic, and CCD UBV photometry, spectroscopic observations, and star counts are presented for the open cluster Berkeley 58 to examine a possible association with the 4.37d Cepheid CG Cas. The cluster is difficult to separate from the early-type stars belonging to the Perseus spiral arm, in which it is located, but has reasonably well-defined parameters: an evolutionary age of ~10^8 years, a mean reddening of E(B-V)_(B0)=0.70+-0.03 s.e., and a distance of 3.03+-0.17 kpc (V_0-M_V=12.40+-0.12 s.d.). CG Cas is a likely cluster coronal member on the basis of radial velocity, and its period increase of +0.170+-0.014 s yr^(-1) and large light amplitude describe a Cepheid in the third crossing of the instability strip lying slightly blueward of strip centre. Its inferred reddening and luminosity are E(B-V)=0.64+-0.02 s.e. and =-3.06+-0.12. A possible K supergiant may also be a cluster member.
Comment: Accepted for Publication (MNRAS)
Databáze: arXiv