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Related papers: Modelling hybrid Beta Cephei/SPB pulsations: Gamma…

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We present interpretation of the oscillation spectrum of the early B-type star $\gamma$ Pegasi, in which both low order p/g and high-order g-modes are observed. Using amplitudes and phases of the photometric and radial velocity variations,…

Solar and Stellar Astrophysics · Physics 2015-06-15 Przemysław Walczak , Jadwiga Daszyńska-Daszkiewicz , Alexey A. Pamyatnykh , Tomasz Zdravkov

We present a comprehensive seismic study of the three pulsating stars of $\beta$ Cep/SPB type: $\nu$ Eridani, 12 Lacertae and $\gamma$ Pegasi. Models with the modified mean opacity profile are constructed in order to account for both the…

Solar and Stellar Astrophysics · Physics 2017-09-13 Przemysław Walczak , Jadwiga Daszyńska-Daszkiewicz , Alexey Pamyatnykh

Using the updated oscillation spectrum of $\gamma$ Pegasi, we construct a set of seismic models which reproduce two pulsational frequencies corresponding to the $\ell=0$, p$_1$ and $\ell=1$, g$_1$ modes. Then, we single out models which…

Solar and Stellar Astrophysics · Physics 2015-05-18 Przemysław Walczak , Jadwiga Daszyńska-Daszkiewicz

The recent detection of both pressure and high-order gravity modes in the classical B-type pulsator Gamma Pegasi offers promising prospects for probing its internal structure through seismic studies. To aid further modelling of this star,…

Solar and Stellar Astrophysics · Physics 2021-03-17 C. P. Pandey , T. Morel , M. Briquet , K. Jayakumar , S. Bisht , B. B. Sanwal

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 Str\"omgren photometry, we…

Solar and Stellar Astrophysics · Physics 2022-03-14 Jadwiga Daszyńska-Daszkiewicz , P. Walczak , A. A. Pamyatnykh , W. Szewczuk

The discovery of $\beta$ Cephei stars in low metallicity environments, as well as the difficulty in theoretically explaining the excitation of the pulsation modes observed in some $\beta$ Cephei and hybrid SPB-$\beta$ Cephei pulsators,…

Astrophysics · Physics 2008-11-26 A. Miglio , J. Montalban , M. -A. Dupret

Hybrid stars like Nu Eridani and 12 Lacertae show two different types of pulsations: (i) low-order acoustic and gravity modes of the Beta Cephei type with periods of about 3-6 hours, and (ii) high-order gravity modes of the SPB type with…

Astrophysics · Physics 2008-10-10 Thomas Zdravkov , Alexey A. Pamyatnykh

The rich oscillation spectra determined for the two stars, Nu Eridani and 12 Lacertae, present an interesting challenge to stellar modelling. The stars are hybrid objects showing a number of modes at frequencies typical for Beta Cep stars…

Astrophysics · Physics 2009-11-13 W. A. Dziembowski , A. A. Pamyatnykh

Results of mode identification and seismic modelling of the $\beta$ Cep/SBP star 12 Lacertae are presented. Using data on the multi-colour photometry and radial velocity variations, we determine or constrain the mode degree, $\ell$, for all…

Solar and Stellar Astrophysics · Physics 2013-04-16 J. Daszyńska-Daszkiewicz , W. Szewczuk , P. Walczak

We have acquired simultaneous high-precision space photometry and radial velocities of the bright hybrid Beta Cep/SPB pulsator Gamma Peg. Frequency analyses reveal the presence of six g modes of high radial order together with eight…

Solar and Stellar Astrophysics · Physics 2015-05-13 G. Handler

We construct seismic models of the four double-mode radial $\delta$ Scuti stars adopting opacities from three databases: OPAL, OP and OPLIB. The aim is to find the models that fit the observed frequencies of the two radial modes and have…

The excitation of pulsation modes in beta Cephei and Slowly Pulsating B stars is known to be very sensitive to opacity changes in the stellar interior where T~2 10^5 K. In this region differences in opacity up to ~50% can be induced by the…

Astrophysics · Physics 2009-11-13 Andrea Miglio , Josefina Montalban , Marc-Antoine Dupret

We analyse time-series observations from the BRITE-Constellation of the well known $\beta$ Cephei type star $\theta$ Ophiuchi. Seven previously known frequencies were confirmed and nineteen new frequency peaks were detected. In particular,…

We present results of a {\bf comprehensive} asteroseismic modelling of the $\beta$ Cephei variable $\theta$ Ophiuchi. {\bf We call these studies {\it complex asteroseismology} because our goal is to reproduce both pulsational frequencies as…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. Daszynska-Daszkiewicz , P. Walczak

We undertake another attempt towards seismic modelling of the most intensive studied main sequence pulsators of the early B spectral type, $\nu$ Eridani. Our analysis is extended by a requirement of fitting not only pulsational frequencies…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Daszyńska-Daszkiewicz , P. Walczak

We present the first extensive seismic modelling of SX Phe stars in the stellar system $\omega$ Cen. First, using the new values of reddening $E(B-V)$ and distance modulus $(m-M)_V$, and bolometric corrections from Kurucz model atmospheres,…

Solar and Stellar Astrophysics · Physics 2025-04-25 J. Daszyńska-Daszkiewicz , P. Walczak , P. Góra , W. Szewczuk

$\nu$ Eridani is a well known multiperiodic $\beta$ Cephei pulsator which exhibits also the SPB (Slowly Pulsating B-type stars) type modes. Recent frequency analysis of the BRITE photometry of $\alpha$ Lupi showed that the star is also a…

Solar and Stellar Astrophysics · Physics 2017-01-06 Przemysław Walczak , Jadwiga Daszyńska-Daszkiewicz , Alexey Pamyatnykh , Gerald Handler , Andrzej Pigulski , BEST

High-mass binary stars are known to show an unexplained discrepancy between the dynamical masses of the individual components and those predicted by models. In this work, we study Sigma Scorpii, a double-lined spectroscopic binary system…

Solar and Stellar Astrophysics · Physics 2015-06-19 A. Tkachenko , C. Aerts , K. Pavlovski , P. Degroote , P. I. Papics , E. Moravveji , H. Lehmann , V. Kolbas , K. Clemer

We carried out a multi-colour time-series photometric study of six stars claimed as "hybrid" p and g mode pulsators in the literature. Gamma Peg was confirmed to show short-period oscillations of the Beta Cep type and simultaneous…

Solar and Stellar Astrophysics · Physics 2015-05-13 G. Handler

We analyze data on pulsation amplitudes and phases for two $\beta$ Cephei stars, $\delta$ Cet and $\nu$ Eri. Str\"omgren photometry and radial velocity measurements are used simultaneously to obtain constraints on mean parameters of the…

Astrophysics · Physics 2009-11-11 J. Daszynska-Daszkiewicz , W. A. Dziembowski , A. A. Pamyatnykh
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