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Related papers: Exploring B4: A Pulsating sdB star, in a Binary, i…

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We present the analysis of time-resolved spectroscopy of the pulsating sdB star PG1605+072. From our main observing run of 16 nights we have detected velocity variations at 5 frequencies that correspond to those found in photometry. Based…

Astrophysics · Physics 2009-11-07 S. J. O'Toole , T. R. Bedding , H. Kjeldsen , T. H. Dall , D. Stello

Hot subdwarf B stars (sdBs) are evolved core helium-burning stars with very thin hydrogen envelopes. In order to form an sdB, the progenitor has to lose almost all of its hydrogen envelope right at the tip of the red giant branch. In binary…

Solar and Stellar Astrophysics · Physics 2015-05-27 S. Geier , L. Classen , U. Heber

Pulsed X-ray emission in the luminous, helium-rich sdO BD+37 442 has recently been discovered (La Palombara et al., 2012). It was suggested that the sdO star has a neutron star or white dwarf companion with a spin period of 19.2 s. After HD…

Solar and Stellar Astrophysics · Physics 2014-04-29 U. Heber , S. Geier , A. Irrgang , D. Schneider , I. Barbu-Barna , S. Mereghetti , N. La Palombara

HD 156424 (B2 V) is a little-studied magnetic hot star in the Sco OB4 association, previously noted to display both high-frequency radial velocity (RV) variability and magnetospheric H$\alpha$ emission. We have analysed the TESS light…

Solar and Stellar Astrophysics · Physics 2021-04-07 M. E. Shultz , Th. Rivinius , G. A. Wade , O. Kochukhov , E. Alecian , A. David-Uraz , J. Sikora , the MiMeS Collaboration

The predicted orbital period histogram of an sdB population is bimodal with a peak at short (< 10 days) and long (> 250 days) periods. Observationally, there are many short-period sdB systems known, but only very few long-period sdB…

We present a picture of the very unusual blue straggler S1082 in the old open cluster M67 whose light is the sum of a close binary (P = 1.0677978 d) and another cluster member. We provide a complete V-band light curve for the system, and…

We present the results of complex seismic modelling of the Slowly Pulsating B-type star HD74560. The star pulsates in five frequencies detected in photometric observations. For all these frequencies, we identify the mode degree, $\ell$. For…

Solar and Stellar Astrophysics · Physics 2015-06-04 Przemysław Walczak , Wojciech Szewczuk , Jadwiga Daszyńska-Daszkiewicz

CS 1246 is a hot subdwarf B star discovered in 2009 to exhibit a single, large-amplitude radial pulsation. An O-C diagram constructed from this mode revealed reflex motion due to the presence of a low-mass M dwarf, as well as a long-term…

The intermediate Helium subdwarf B star LS IV$-$14$^\circ$116 is a unique object showing extremely peculiar atmospheric abundances as well as long-period pulsations that cannot be explained in terms of the usual opacity mechanism. One…

Solar and Stellar Astrophysics · Physics 2015-04-01 S. K. Randall , S. Bagnulo , E. Ziegerer , S. Geier , G. Fontaine

DH Cephei is a prominent O+O-type binary system in the NGC 7380 open cluster. Our high-precision multi-band polarimetry demonstrates synchronous linear polarization variations with the orbital period. Using Stokes parameters, we derived the…

Solar and Stellar Astrophysics · Physics 2023-09-13 Yasir Abdul Qadir , Andrei V. Berdyugin , Vilppu Piirola , Takeshi Sakanoi , Masato Kagitani

We present an analysis of the binary and physical parameters of a unique pulsating white dwarf with a main-sequence companion, SDSS J1136+0409, observed for more than 77 d during the first pointing of the extended Kepler mission: K2…

Pulsating stars in eclipsing binary systems play an important role in asteroseismology. The combination of their spectroscopic and photometric orbital solutions can be used to determine, or at least to constrain, the masses and radii of…

Solar and Stellar Astrophysics · Physics 2014-03-05 D. Drobek , A. Pigulski

BG Gem is an eclipsing binary with a 91.6-day orbital period. The more massive primary component does not seem to show absorption lines in the spectrum, while the less massive secondary is thought to be a K-type star, possibly a supergiant.…

Solar and Stellar Astrophysics · Physics 2013-05-13 N. A. Drake , A. S. Miroshnichenko , S. Danford , C. B. Pereira

Massive stars are important building blocks of the Universe, and their stellar structure and evolution models are fundamental cornerstones of various fields in modern astrophysics. The precision of these models is limited by our lack of…

PG 0014+067 is one of the most promising pulsating subdwarf B stars for seismic analysis, as it has a rich pulsation spectrum. The richness of its pulsations, however, poses a fundamental challenge to understanding the pulsations of these…

Astrophysics · Physics 2019-08-15 M. Vuckovic , S. D. Kawaler

We present rotational and astrometric parameters of three millisecond pulsars located near the center of the globular cluster NGC 6266 (M62) resulting from timing observations with the Parkes radio telescope. Their accelerations toward the…

Astrophysics · Physics 2009-11-10 A. Possenti , N. D'Amico , R. N. Manchester , F. Camilo , A. G. Lyne , J. Sarkissian , A. Corongiu

We present the list of variable stars we found in the Kepler superstamp data covering approximately 9 arcminutes from the central region of NGC 6791. We classified the variable stars based on the variability type and we established their…

Solar and Stellar Astrophysics · Physics 2023-03-15 Sachu Sanjayan , Andrzej S Baran , Peter Nemeth , Karen Kinemuchi , Jakub Ostrowski , Sumanta Kumar Sahoo

We present an analysis of oscillation mode variability in the hot B subdwarf star EPIC~220422705, a new pulsator discovered from $\sim78$~days of {\em K}2 photometry. The high-quality light curves provide a detection of 66 significant…

Solar and Stellar Astrophysics · Physics 2022-07-27 Xiao-Yu Ma , Weikai Zong , Jian-Ning Fu , M. D. Reed , Jiaxin Wang , Stephane Charpinet , Jie Su

We present the results of a long-term variability survey of the old open cluster NGC 6791. The BVI observations, collected over a time span of 6 years, were analyzed using the ISIS image subtraction package. The main target of our…

Astrophysics · Physics 2009-11-07 B. J. Mochejska , K. Z. Stanek , J. Kaluzny

V746 Cas is known to be a triple system composed of a close binary with an alternatively reported period of either 25.4d or 27.8d and a third component in a 62000d orbit. The object was also reported to exhibit multiperiodic light…

Solar and Stellar Astrophysics · Physics 2017-12-27 P. Harmanec , M. Brož , P. Mayer , P. Zasche , L. Kotková , J. A. Nemravová , R. J. Dukes , D. Korčáková , M. Šlechta , E. Kıran , R. Kříček , J. Juryšek
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