Article
Astronomy & Astrophysics
D. L. Holdsworth, M. S. Cunha, D. W. Kurtz, V Antoci, D. R. Hey, D. M. Bowman, O. Kobzar, D. L. Buzasi, O. Kochukhov, E. Niemczura, D. Ozuyar, F. Shi, R. Szabo, A. Samadi-Ghadim, Zs Bognar, L. Fox-Machado, V Khalack, M. Lares-Martiz, C. C. Lovekin, P. Mikolajczyk, D. Mkrtichian, J. Pascual-Granado, E. Paunzen, T. Richey-Yowell, A. Sodor, J. Sikora, T. Z. Yang, E. Brunsden, A. David-Uraz, A. Derekas, A. Garcia Hernandez, J. A. Guzik, N. Hatamkhani, R. Handberg, T. S. Lambert, P. Lampens, S. J. Murphy, R. Monier, K. R. Pollard, P. Quitral-Manosalva, A. Ramon-Ballesta, B. Smalley, I Stateva, R. Vanderspek
Summary: This study presents the discovery of 12 new rapidly oscillating Ap stars through TESS observations, including stars with the longest and shortest pulsation periods, as well as those with multiperiodic variability. Nearly 60% of the sample stars exhibit multiperiodic behavior, providing valuable cases for testing models of roAp pulsations and obtaining asteroseismic results. The study also reports a conundrum in applying the oblique pulsator model to roAp stars and the second case of non-linear mode interactions in a specific star.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
H. Netzel, L. Molnar, E. Plachy, J. M. Benko
Summary: This article utilizes samples of first-overtone RR Lyrae stars observed by the Kepler telescope during the K2 mission to search for and characterize additional low-amplitude signals. The study discovers new sequences of period ratios and unknown periodicity phenomena.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
E. Distefano, A. C. Lanzafame, E. Brugaletta, B. Holl, A. F. Lanza, S. Messina, I. Pagano, M. Audard, G. Jevardat De Fombelle, I. Lecoeur-Taibi, N. Mowlavi, K. Nienartowicz, L. Rimoldini, D. W. Evans, M. Riello, P. Garcia-Lario, P. Gavras, L. Eyer
Summary: This study presents a new catalogue of stars with variability induced by magnetic activity, generated using Gaia satellite data. The catalogue includes 474,026 stars, of which approximately 430,000 are newly discovered variables. The catalogue provides various parameters for each star, with the most important being the stellar rotation period, photometric amplitude of the rotational modulation signal, and the Pearson correlation coefficient between magnitude and colour variation.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
R. Gomel, T. Mazeh, S. Faigler, D. Bashi, L. Eyer, L. Rimoldini, M. Audard, N. Mowlavi, B. Holl, G. Jevardat, K. Nienartowicz, I. Lecoeur, L. Wyrzykowski
Summary: As part of Gaia Data Release 3, a large number of ellipsoidal variables were identified using supervised classification. These variables show periodic variability, presumably due to tidal interaction with a companion in a close binary system. Based on observed ellipsoidal amplitudes, a subset of 6306 short-period probable ellipsoidal variables with significant Gaia G-band photometric modulations suggest the presence of a massive, undetected secondary. Further investigations, including follow-up observations, are needed to confirm the true nature of these variables.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Zsofia Bognar, Adam Sodor, Ian R. Clark, Steven D. Kawaler
Summary: This study compared the observations of ZZ Ceti stars obtained by the TESS Space Telescope in two observational seasons, and discovered new possible pulsation modes. It also found that the star HE 0532-5605 exhibits recurring brightening phases, indicating its nature as a new outbursting DAV star. Additionally, a lower-amplitude brightening phase in WD J0925+0509 was determined to be caused by a Solar System object passing in the foreground. Asteroseismic model solutions were accepted for six stars.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
L. A. Balona
Summary: High-precision photometry from TESS has uncovered a group of over 500 stars that pulsate at high frequencies, contradicting model predictions. These anomalous variables, possibly historical Maia variables, exhibit rotational velocities comparable to main sequence or SPB stars in the same temperature range. Some Maia stars even pulsate at frequencies typical of roAp stars. This suggests that Maia stars should be considered an extension of delta Scuti variables rather than a separate class, with effective temperatures reaching as high as 18,000 K. The TESS data also show a continuous sequence of low-frequency pulsating stars connecting gamma Doradus and SPB variables, which is not predicted by models. This indicates that multiple driving mechanisms, potentially including convection, play a significant role.
FRONTIERS IN ASTRONOMY AND SPACE SCIENCES
(2023)
Article
Astronomy & Astrophysics
Jie Yu, Saskia Hekker, Timothy R. Bedding, Dennis Stello, Daniel Huber, Laurent Gizon, Shourya Khanna, Shaolan Bi
Summary: The study investigated the relationships between mass-loss, pulsations, and radiation in red giants, revealing that mass-loss rates are controlled by pulsation-enhanced dust-driven outflows, and vary with pulsation periods and luminosities of red giants, with mass-loss rates in Miras independent of luminosity. This indicates that mass-loss is not currently a limiting factor for stellar age estimates in galactic archaeology studies.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Brian D. Davis, Howard E. Bond, Michael H. Siegel, Robin Ciardullo
Summary: We conducted a search for above-horizontal-branch stars in 97 Galactic and 7 Magellanic Cloud globular clusters. Through photometry and astrometry, we identified 438 stars and classified them into three groups based on their evolutionary paths: AHB1, Post-AGB, and AHB2. We also found that the majority of W Vir variables are evolving towards lower temperatures and suggest that nonvariable yellow PAGB stars can be used as a standard candle for distance measurement.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
G. Csoernyei, L. Szabados, L. Molnar, B. Cseh, N. Egei, Cs Kalup, V Kecskemethy, R. Koenyves-Toth, K. Sarneczky, R. Szakats
Summary: Investigating the period changes of classical Cepheids through the framework of O - C diagrams provides insights into their evolution and nature. This study presents new or extended O - C diagrams for 148 Galactic classical Cepheids, and finds observational indications of period change rate dependence on the horizontal position within the instability strip. Period fluctuations are observed in 59 Cepheids, which are uniformly distributed over the inspected period range. The fluctuation amplitude is found to be dependent on the pulsation period, similar to longer period pulsating variable stars.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Johanna Jurcsik, Aron Juhasz
Summary: The study showed that some stars have light curves very similar to typical bulge RR Lyrae stars based on Fourier parameters. Calculating the physical properties revealed that short-period stars are less metal-poor, fainter, smaller, and hotter than long-period variables.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
F. Kahraman Alicavus, C. G. Coban, E. Celik, D. S. Dogan, O. Ekinci, F. Alicavus
Summary: In this study, researchers discovered 42 new δ Scuti stars through observations of the southern TESS field. They used an algorithm to search for detached and semidetached binary systems and confirmed these candidates through visual inspection and light curve analysis. By calculating their physical parameters and analyzing their positions on the H-R diagram, they further investigated the internal structure and evolution of these stars.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
J. Labadie-Bartz, S. Huemmerich, K. Bernhard, E. Paunzen, M. E. Shultz
Summary: This study investigates the photometric variability of 1002 magnetic chemically peculiar (mCP) stars, determines their rotational periods, and identifies interesting objects for further studies. The results show that the rotation periods of the stars are related to their evolutionary stages, which supports the assumption of angular momentum conservation during the main-sequence evolution.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Michele Trabucchi, Peter R. Wood, Nami Mowlavi, Giada Pastorelli, Paola Marigo, Leo Girardi, Thomas Lebzelter
Summary: The study finds that non-linear models for long-period variability in luminous red giants can more accurately predict pulsation periods and have better agreement with observations compared to linear models. In addition to providing simple analytical relations based on mass and radius, the research also investigates the impact of turbulent viscosity on pulsation and possible effects of varying metallicity and carbon abundance.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
J. Adassuriya, S. Ganesh, J. L. Gutierrez, G. Handler, Santosh Joshi, K. P. S. C. Jayaratne, K. S. Baliyan
Summary: In this study, high temporal resolution ground- and space-based photometric observations of SZ Lyncis were analyzed, revealing multiple frequencies and modes and providing insights into the physical parameters and mass estimation.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Ata Sarajedini, Sevinc Gokmen
Summary: This study compares two relations for calculating the metal abundance of ab-type RR Lyrae variables and determines that knowing only the period of these variables is sufficient to determine the mean metallicity of a globular cluster. Both tested equations accurately reproduce the spectroscopic metal abundance of each cluster, with an accuracy of ±0.28 dex.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
K. Vida, K. Olah, Zs. Kovari, J. Jurcsik, A. Sodor, M. Varadi, B. Belucz, I. Dekany, Zs. Hurta, I. Nagy, K. Posztobanyi
ASTRONOMISCHE NACHRICHTEN
(2010)
Article
Astronomy & Astrophysics
G. Hajdu, J. Jurcsik, A. Sodor, B. Szeidl, P. Smitola, B. Belucz, K. Posztobanyi, K. Vida, E. Kun
ASTRONOMISCHE NACHRICHTEN
(2012)
Article
Astronomy & Astrophysics
K. Olah, H. Korhonen, K. Vida, I. Ilyin, T. H. Dall, S. P. Jarvinen, J. Jurcsik, M. I. Andersen, A. A. Djupvik, T. Pursimo, A. Moor, J. Datson, R. Karjalainen, T. Liimets, J. Kubat, A. Kawka
ASTRONOMY & ASTROPHYSICS
(2010)
Article
Astronomy & Astrophysics
J. Jurcsik, P. Smitola, G. Hajdu, C. Pilachowski, K. Kolenberg, A. Sodor, G. Furesz, A. Moor, E. Kun, A. Saha, P. Prakash, P. Blum, I. Toth
ASTROPHYSICAL JOURNAL LETTERS
(2013)
Article
Astronomy & Astrophysics
J. Jurcsik, A. Sodor, B. Szeidl, Z. Kollath, H. A. Smith, Zs. Hurta, M. Varadi, A. Henden, I. Dekany, I. Nagy, K. Posztobanyi, A. Szing, K. Vida, N. Vityi
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2009)
Article
Astronomy & Astrophysics
A. Sodor, J. Jurcsik, B. Szeidl, M. Varadi, A. Henden, K. Vida, Zs. Hurta, K. Posztobanyi, I. Dekany, A. Szing
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2011)
Article
Astronomy & Astrophysics
J. Jurcsik, G. Hajdu, B. Szeidl, K. Olah, J. Kelemen, A. Sodor, A. Saha, P. Mallick, J. Claver
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2012)
Article
Astronomy & Astrophysics
J. Jurcsik, B. Szeidl, C. Clement, Zs Hurta, M. Lovas
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2011)
Article
Astronomy & Astrophysics
B. Szeidl, Zs Hurta, J. Jurcsik, C. Clement, M. Lovas
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2011)
Article
Astronomy & Astrophysics
J. Jurcsik, A. Sodor, G. Hajdu, B. Szeidl, A. Dozsa, K. Posztobanyi, P. Smitola, B. Belucz, V. Feher, Zs Kovari, L. Kriskovics, E. Kun, L. Molnar, I. Nagy, K. Vida, N. Goeroeg
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2012)
Article
Astronomy & Astrophysics
B. Szeidl, J. Jurcsik, A. Sodor, G. Hajdu, P. Smitola
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2012)
Article
Astronomy & Astrophysics
A. Sodor, G. Hajdu, J. Jurcsik, B. Szeidl, K. Posztobanyi, Zs. Hurta, B. Belucz, E. Kun
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2012)
Article
Astronomy & Astrophysics
G. Hajdu, M. Catelan, J. Jurcsik, I. Dekany, A. J. Drake, J-B. Marquette
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2015)
Article
Astronomy & Astrophysics
J. Jurcsik, P. Smitola, G. Hajdu, J. Nuspl
ASTROPHYSICAL JOURNAL LETTERS
(2014)
Article
Astronomy & Astrophysics
J. Jurcsik, P. Smitola, G. Hajdu, A. Sodor, J. Nuspl, K. Kolenberg, G. Furesz, A. Moor, E. Kun, A. Pal, J. Bakos, J. Kelemen, T. Kovacs, L. Kriskovics, K. Sarneczky, T. Szalai, A. Szing, K. Vida
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2015)