A CCD Search for Variable Stars of Spectral Type B in the Northern Hemisphere Open Clusters. VI. NGC 6910

• Autorzy: Kołaczkowski Z. , Pigulski A. , Kopacki G. , Michalska G.
• Języki publikacji: EN

Abstrakty

EN

We present results of variability search in the field of the young open cluster NGC 6910. We found four &beta Cep-type stars in the cluster, which makes it rather exceptional among the northern clusters observed in our project. Two of these &beta Cep stars show three modes with amplitudes above the detection level, in the remaining two we detect single modes. We discuss the possibility that the large number of &beta Cep stars in NGC 6910 is due to higher metallicity of the cluster. In addition, we found four other variables, one ellipsoidal or eclipsing binary and three that show irregular variations. The latter three stars have Hα in emission. We also provide VI_C photometry for 139 stars down to V=16.6 mag and Hα photometry for 73 stars. Using this photometry we estimate the cluster age to be equal to 6±2 Myr, and the distance modulus, 11.0±0.3 mag. The reddening is high and variable across the cluster. In terms of the E(V-I_C) color-excess it amounts to 1.25-1.7 mag, corresponding to E(B-V) between 1.0 mag and 1.4 mag. The average reddening in the central field is E(V-I_C)=1.47±0.04 mag.

Słowa kluczowe

EN

stars: early-type; stars: oscillations; stars: emission-line; stars:Be; open clusters: individual: NGC 6910; associations: individual: NGC 6910

• Wydawca: Copernicus Foundation for Polish Astronomy
• Czasopismo: Acta Astronomica
• Rocznik: 2004
• Tom: Vol. 54, No. 1
• Strony: 33--55
• Opis fizyczny: Bibliogr. 78 poz, rys., tab., wykr.

Twórcy

autor

Kołaczkowski Z.

• Wrocaw University Observatory, ul. Kopernika 11, 51-622 Wrocław, Poland

autor

Pigulski A.

• Wrocaw University Observatory, ul. Kopernika 11, 51-622 Wrocław, Poland

autor

Kopacki G.

• Wrocaw University Observatory, ul. Kopernika 11, 51-622 Wrocław, Poland

autor

Michalska G.

• Wrocaw University Observatory, ul. Kopernika 11, 51-622 Wrocław, Poland

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