Vibrational stability of pre-main sequence stars

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2004

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Burhan, Mehmet

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In this study, vibrational properties and stability of delta-Scuti like pulsating pre-main sequence stars have been investigated. Studies were held in the mass range 2-4 Mo and limited to radial linear adiabatic pulsations. Numerical computations were performed by the oscillation program written by Kırbıyık & Al-Murad (1993). The models were selected to be at the latest phases of the pre-main sequence evolution where the luminosity starts to increase. We have limited our calculations upto the end of the radiative inner regions, since at the surface of the star, our adiabatic perturbation computation does not perfectly fit to the relatively thin non-adiabatic convective envelope of the star. The results of the stability analysis showed that the PMS models undergo an instability whose time period is a function of mass. Instability Strip of pulsating PMS stars was re-drawn with comparison to M. Marconi & F.Palla (1998). The effect of gravitational contraction on stability was also investigated.

Subject Keywords

Astrophysics (General)

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http://etd.lib.metu.edu.tr/upload/12604705/index.pdf
https://hdl.handle.net/11511/16912

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. Burhan, “Vibrational stability of pre-main sequence stars,” M.S. - Master of Science, Middle East Technical University, 2004.