Long-Term period and Amplitude Variations in β Cephei Stars
نویسندگان
چکیده
منابع مشابه
Amplitude Saturation in β Cephei Models
Although the driving mechanism acting in β Cephei pulsators is well known (e.g. Dziembowski & Pamyatnykh 1993), problems concerning identification of amplitude limitation mechanism and non-uniform filling of the theoretical instability strip, remain to be solved. In the present analysis, these problems are addressed by non-linear modelling of radial pulsations of these stars. In this approach r...
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In this paper, we present new observations of β Cephei stars made with the CFHT coudé Reticon. Spectral sequences of the extreme star BW Vulpeculae show large velocity and line profile changes in Ha and in the CII doublet (λλβ578,6582) over 0.04 of a cycle, during three different cycles on three different nights. In fact, there are two such phases of line doubling where the velocities are nearl...
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We present preliminary results concerning amplitude saturation in β Cephei models. Using nonlinear approach we have investigated amplitude limitation mechanism in β Cephei stars. In our approach radial modes have been treated as representative for all acoustic oscillations. We have studied pulsation properties of several models (7–20 M ⊙ , Z = 0.02, 0.015) using radiative Lagrangean hydrocodes ...
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ژورنال
عنوان ژورنال: Highlights of Astronomy
سال: 1998
ISSN: 1539-2996
DOI: 10.1017/s1539299600020980