Asteroseismology of the double-radial mode $\delta$ Scuti star BP Pegasi

Abstract

Using the ASAS data, we determine the pulsational frequencies of the high-amplitude $\delta$ Sct star BP Pegasi. The analysis revealed only the two known, independent frequencies. On the basis of multicolour Strömgren photometry, we independently find that both frequencies can only be associated with radial modes which, according to the frequency ratio, are fundamental and first overtone modes. The models fitting the two frequencies depend strongly on the opacity data. For low values of the mixing length parameter ${\alpha }_{\mathrm{MLT}}\approx 0.5$, only the OPAL seismic models in the post-main sequence phase of evolution are caught within the observed error box. Seismic OP and OPLIB models can only reach the error box if we increase ${\alpha }_{\mathrm{MLT}}$ to at least 2.0. Then, including the non-adiabatic parameter $f$ into our seismic modelling, we constrain various parameters, employing Monte Carlo-based Bayesian analysis.

16 pages, 15 figures, 6 tables, accepted for publication in MNRAS

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Cited by in corpus (11)

• Unveiling the Intricate Symphony of Nonlinear Pulsation Mode Interactions in High-Amplitude $\delta$ Scuti Stars
• A need to revise stellar opacities from asteroseismology of $\delta$ Scuti stars
• Pulsation Analysis of High-Amplitude $\delta$ Scuti Stars with TESS
• Precise Evolutionary Asteroseismology of High-Amplitude δ Scuti Star AE Ursae Majoris
• Uncorrelated Amplitude and Frequency Variations of the Harmonics in SX Phoenicis Star XX Cygni
• TESS Observations of Seven Newly Identified High-amplitude $\delta$ Scuti Stars
• Asteroseismology of double-mode radial $\delta$ Scuti stars: AE Ursae Majoris and RV Arietis
• Discovery of resonating integration modes in triple-mode high-amplitude $\delta$ Scuti stars: A new evolutionary phase indicator
• Exploring the unexpected: Disharmonized harmonic pulsation modes in high-amplitude $\delta$ Scuti stars
• Period Variation Rates of Four Radial Single-Mode High-Amplitude Delta Scuti Stars
• Discovery and Characterization of Three New High-amplitude delta Scuti Stars from TESS Observations