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We present a review of the latest results of studies of the class of mass-accreting pulsating components of semi-detached eclipsing binaries known as oEA stars. The application of the techniques of asteroseismology to this class of stars unlocks new pathways for gaining a deeper understanding of the short-term evolution and magnetic activity of binary stars. We report the discovery of 49 new pulsating components of eclipsing binaries, based on data from NASA’s TESS space telescope. Recent observational results on the pulsation characteristics of these stars are summarized. The effects of the interaction of the magnetic and spot activity of the Roche-lobe-filling component of a system with the pulsations of the mass-accreting component are discussed.

We present a brief review of the recent results of photometric and spectroscopic surveys and 3-D hydrodynamic simulations of the mass- transfer for the class of oscillating mass-accreting components of Algols (oEA stars). These ground-based spectroscopic and space-based photometric surveys are aimed at detecting and studying the spectra of non- radial oscillations, to get precise orbits and parameters of the binaries, and studying the spectroscopic and the hydrodynamic nature of the mass- transfer. We discovered 47 new oEA stars in TESS data and carried out follow up spectroscopic observations of known and new oEA stars with the SALT telescope. We found that the co-existence of excitation of high-degree non-radial modes with a wide spectrum of low-degree modes is a common phenomenon in oEA stars.

We describe a flexible data reduction package for high resolution cross-dispersed echelle data. This open-source package is developed in Python and includes optional GUIs for most of the steps. It does not require any pre-knowledge about the form or position of the echelle-orders. It has been tested on cross-dispersed echelle spectrographs between 13k and 115k resolution (bifurcated fiber-fed spectrogaph ESO-HARPS and single fiber-fed spectrograph TNT-MRES). HiFLEx can be used to determine radial velocities and is designed to use the TERRA package but can also control the radial velocity packages such as CERES and SERVAL to perform the radial velocity analysis. Tests on HARPS data indicates radial velocities results within ±3 m s−1 of the literature pipelines without any fine tuning of extraction parameters.

We describe a flexible data reduction package for high resolution cross-dispersed echelle data. This open-source package is developed in Python and includes optional GUIs for most of the steps. It does not require any pre-knowledge about the form or position of the echelle-orders. It has been tested on cross-dispersed echelle spectrographs between 13k and 115k resolution (bifurcated fiber-fed spectrogaph ESO-HARPS and single fiber-fed spectrograph TNT-MRES). HiFLEx can be used to determine radial velocities and is designed to use the TERRA package but can also control the radial velocity packages such as CERES and SERVAL to perform the radial velocity analysis. Tests on HARPS data indicates radial velocities results within 3 m s−1 of the literature pipelines without any fine tuning of extraction parameters.

We present results of a first application of a new computer program for modeling spectroscopic line profiles of eclipsing binaries including eclipse mapping. We apply the program to observed spectra of the oEA star RZ Cas. Basic stellar parameters of RZ Cas are derived from an optimization of the model parameters and compared to those derived from the light curves using the Wilson-Devinney code. Results are in a very good agreement. The comparison of the O-C values obtained from the spectra taken in 2001 and in 2006 support the assumption that a transient phase of rapid mass-transfer occurred in RZ Cas near to the year 2001.

We present the detection of a rich l 0-2 p-mode oscillation spectrum in the most chemically-peculiar roAp star HD 101065 (Przybylski's star). Constructed echelle-diagrams exhibit both large (Δν 64.07 μHz) and small (5-7 μHz) frequency spacings. We have calculated the nonadiabatic frequencies of axisymmetric high-order p-modes using main sequence models with dipole magnetic fields and masses ranging from 1.5 to 1.7 M⨀. Two sets of chemical composition (X,Z) (0.7, 0.02) and (0.695, 0.025) were adopted. We find the model with Z 0.02, log Teff 3.8150, log L/L⨀ 0.7710, M 1.50 M⨀, Age 1.6 109yr, Bp 9.00 kG fits the observed oscillation spectrum very well. Further progress in improving the asteroseismic modelling of Przybyzlski's star requires increasing the accuracy of determination of oscillation spectrum with mode spacings less than 1μHz.

The study of variable stars has played a central role in astronomy for over 400 years, and more so in the present than at any time in history. Stars, especially variable stars, are astrophysical laboratories for understanding physical processes in the universe. Stars represent the fundamental components of stellar systems, galaxies and the universe.

Aims. In order to search for and study the nature of the low-amplitude and long-periodic radial velocity (RV) variations of massive stars, we have been carrying out a precise RV survey for supergiants that lie near or inside the Cepheid instability strip. Methods. We have obtained high-resolution spectra of {\\alpha} Per (F5 Ib) from November 2005 to September 2011 using the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) at Bohyunsan Optical Astronomy Observatory (BOAO). Results. Our measurements reveal that {\\alpha} Per shows a periodic RV variation of 128 days and a semi-amplitude of 70 m/s. We find no strong correlation between RV variations and bisector velocity span (BVS), but the 128-d peak is indeed present in the BVS variations among several other significant peaks in periodogram. Conclusions. {\\alpha} Per may have an exoplanet, but the combined data spanning over 20 years seem to suggest that the 128-d RV variations have not been stable on long-term scale, which is somewhat difficult to reconcile with the exoplanet explanation. We do not exclude the pulsational nature of the 128-d variations in {\\alpha} Per. Although we do not find clear evidence for surface activity or rotational modulations by spots, coupled with the fact that the expected rotation period is ~ 130 days the rotational modulation seems to be the most likely cause of the RV variations. More observational data and research are needed to clearly determine the origin of RV the variations in {\\alpha} Per.

We present the results of the high-resolution (R\\(\\sim\\)60,000) spectroscopic analysis of the star LAMOSTJ045019.27+394758.7 (hereafter J045) from the list of carbon stars of LAMOST DR2. From our analysis, we find that J045 does not exhibit the spectral characteristics of carbon stars. It is found to be a metal-poor ( [Fe/H] = \\(-\\)1.05) giant that shows very unusual elemental abundances, particularly for N, Na, V, and Zn. J045 shows \\({\\alpha}\\)-elements (Mg, Si, Ca) with near-solar values (\\(<\\)[\\(\\alpha\\)/Fe]\\(>\\) = 0.09) in contrast to Galactic stars that show [\\(\\alpha\\)/Fe] in the range 0.2 to 0.3 dex. In J045, Sc and Ti are under abundant with [X/Fe] \\(\\le\\) \\(-\\)0.25. Vanadium gives [V/Fe] = 0.51 and zinc is under-abundant with [Zn/Fe] = \\(-\\)0.62. The object exhibits near-solar abundances for Sr, Y, Ba, Pr, and Sm. The La is marginally enhanced, and Ce and Nd are marginally under-abundant in J045. With [Ba/Eu] = \\(-\\)0.38, the object falls into the category of neutron-capture rich r-I stars. The estimated abundances of various elements show that the observed abundance pattern is not compatible with the abundances characteristic of Galactic metal-poor stars but matches quite closely with the abundance pattern of Sculptor Dwarf galaxy stars of similar metallicity. Based on the above observational evidences, we suggest that the object is a possible Sculptor Dwarf Galaxy escapee.

The National Astronomical Research Institute of Thailand (NARIT) has a manifold network of small telescopes installed worldwide. These telescopes serve educational and research purposes and are equipped mainly with CCD detectors for direct imaging and photometry. To extend the possible field of applications, several telescopes were fitted with commercially available medium-resolution spectrographs eShel from Shelyak. With these devices, researchers in NARIT obtained a versatile tool for stellar spectroscopy. Here we describe the current status of available equipment, possible ways of upgrading, and briefly introduce the achieved results of the asteroseismologic study of fast-rotating stars.