Article
Astronomy & Astrophysics
Abigail H. Chown, Victoria Scowcroft, Stijn Wuyts
Summary: The Cepheid Leavitt Law is a key tool for assembling the cosmic distance ladder, and has been used with data from the OGLE-IV catalog and the Spitzer Space Telescope to determine the Period-Luminosity relation for the Magellanic Clouds. The calibrated relations for the LL in the Magellanic Clouds were established using a Monte Carlo Markov Chain template fitting procedure, with the zero-point of the LL calibrated using parallaxes of Milky Way Cepheids from the Hubble Space Telescope and Gaia Data Release 2.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
R. Smolec, O. Ziolkowska, M. Ochalik, M. Sniegowska
Summary: We analyzed Optical Gravitational Lensing Experiment photometry to search for additional periodicities beyond radial modes in classical Cepheids in the Large and Small Magellanic Clouds. We found new candidates for double-mode radial pulsations as well as other signals that cannot be attributed to radial modes. The statistical properties of these signals were analyzed, and a significant fraction were identified as non-radial modes. The study also unveiled differences in additional frequency content between the two Clouds.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
F. Espinoza-Arancibia, M. Catelan, G. Hajdu, N. Rodriguez-Segovia, G. Boggiano, K. Joachimi, C. Munoz-Lopez, C. Ordenes-Huanca, C. Orquera-Rojas, P. Torres, A. Valenzuela-Navarro
Summary: Studying pulsating stars through evolutionary tracks, theoretical instability strips, and period data can offer insights into their properties. The inclusion of Radial Stellar Pulsations as a new functionality aids in obtaining theoretical instability strip edges and linear periods. Relationships between period and other parameters were found in the study.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
N. Rodriguez-Segovia, G. Hajdu, M. Catelan, F. Espinoza-Arancibia, G. Boggiano, C. Cenzano, E. H. Garces, K. Joachimi, C. Munoz-Lopez, C. Ordenes-Huanca, C. Orquera-Rojas, P. Torres, A. Valenzuela-Navarro
Summary: Studying PCR as a probe of changes in the interior structure and evolutionary stages of classical Cepheids in the LMC, researchers obtained accurate PCR values for 1303 stars, the largest single galaxy sample to date. The derived PCR values are largely consistent with theoretical expectations and previous computations, with the discovery of cyclic behavior in long-period sources and two first-crossing Cepheid candidates.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
V. Ramachandran, L. M. Oskinova, W. -R. Hamann
Summary: This study reports the first discovery of O-type stars in the Magellanic Bridge, indicating ongoing star formation and the potential for producing massive O stars in the tidally stripped galactic tails. The discovered O stars in the Bridge exhibit chemically distinct properties, with some stars having abundances similar to the Large Magellanic Cloud and others being metal depleted. The research suggests the presence of a chemically inhomogeneous interstellar medium in the Bridge.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Mojgan Aghakhanloo, Nathan Smith, Jennifer Andrews, Knut Olsen, Gurtina Besla, Yumi Choi
Summary: This study investigates the kinematics of LBVs in the LMC and finds that LBVs have a higher velocity dispersion and more runaway stars compared to red supergiants. It suggests that LBVs are preferentially kicked by a companion's supernova explosion. The study also discovers binary companions in some LBVs and identifies a new LBV.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Kerdaris Kurbah, Sukanta Deb, Shashi M. Kanbur, Susmita Das, Mami Deka, Anupam Bhardwaj, Hugh Riley Randall, Selim Kalici
Summary: In this study, theoretical light curves were generated using the MESA-RSP code, and theoretical and observed Fourier parameters were compared. The multiphase period-luminosity (PL) relations were found to be more stringent in testing models, and adding the R-21 term to the PL relation improved the agreement between the distances to LMC/SMC determined using long period Cepheids and literature values.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
V Ripepi, G. Catanzaro, R. Molinaro, M. Gatto, G. De Somma, M. Marconi, M. Romaniello, S. Leccia, I Musella, E. Trentin, G. Clementini, V Testa, F. Cusano, J. Storm
Summary: Classical Cepheids are crucial for the extragalactic distance scale, with their period-luminosity and period-Wesenheit relations showing dependency on metallicity. This metallicity dependence significantly affects the intercept of the PLZ/PWZ relations, indicating a larger impact than previously thought. However, it remains inconclusive whether the slope of these relationships also depends on metallicity. The correction of Gaia parallaxes' zero-point offset reduces the size of metallicity dependence on the PLZ/PWZ relations.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Martino Romaniello, Adam Riess, Sara Mancino, Richard Anderson, Wolfram Freudling, Rolf-Peter Kudritzki, Lucas Macri, Alessio Mucciarelli, Wenlong Yuan
Summary: This study measured the iron and oxygen abundances of classical Cepheids in the Large Magellanic Cloud (LMC) to understand the influence of chemical composition on their luminosity. The distribution of iron in LMC Cepheids can be accurately described by a single Gaussian, and the uniformity of abundance suggests that they cannot provide meaningful constraints on the dependence of the Cepheid period-luminosity relation on chemical composition at any wavelength.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
V. Ripepi, G. Clementini, R. Molinar, S. Leccia, E. Plachy, L. Molnar, L. Rimoldini, I. Musella, M. Marconi, A. Garofalo, M. Audard, B. Holl, D. W. Evans, G. Jevardat de Fombelle, I. Lecoeur-Taibi, O. Marchal, N. Mowlavi, T. Muraveva, K. Nienartowicz, P. Sartoretti, L. Szabados, L. Eyer
Summary: This article discusses the importance of pulsating stars known as Cepheids in astrophysics, particularly in determining extragalactic distances and studying the Milky Way. The Gaia DR3 catalogue is also presented, which includes data on 15006 Cepheids from various locations.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Vincenzo Ripepi, Laurent Chemin, Roberto Molinaro, Maria-Rosa L. Cioni, Kenji Bekki, Gisella Clementini, Richard de Grijs, Giulia De Somma, Dalal El Youssoufi, Leo Girardi, Martin A. T. Groenewegen, Valentin Ivanov, Marcella Marconi, Paul J. McMillan, Jacco Th van Loon
Summary: We analyzed the Y, J, and K-s light curves of delta Cepheid stars (DCEPs) in the Large Magellanic Cloud (LMC) using the VISTA near-infrared YJK(s) survey. We found a break in the period-luminosity and period-Wesenheit PW relationships for 1O DCEPs at P = 0.58 d. By calculating the individual distances of DCEPs in the LMC, we determined the position angle and inclination of the galaxy. Additionally, we observed non-planar distribution and a flared, thick disc structure in the LMC.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
S. de Wit, A. Z. Bonanos, F. Tramper, M. Yang, G. Maravelias, K. Boutsia, N. Britavskiy, E. Zapartas, E. Zapartas
Summary: This study aims to derive the surface properties of a spectroscopic sample of 14 dusty sources in the Magellanic Clouds using the Baade telescope. Eight new red supergiants, one bright giant, and a new yellow supergiant were identified. The spectral type of a supergiant B[e] star was found to vary over time. The results obtained can help to measure the mass-loss rates from circumstellar dust expelled from the star through outbursts.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
V. F. Braga, G. Fiorentino, G. Bono, P. B. Stetson, C. E. Martinez-Vazquez, S. Kwak, M. Tantalo, M. Dall'Ora, M. Di Criscienzo, M. Fabrizio, M. Marengo, S. Marinoni, P. M. Marrese, M. Monelli
Summary: We investigated the properties of mixed-mode RR Lyrae variables in the Fornax dwarf spheroidal galaxy and compared them with variables in the Magellanic Clouds and nearby dwarf spheroidals. We found that the ratio of mixed-mode RR Lyrae decreases with metallicity, and Fornax fills a period gap in the Petersen diagram similarly to Small Magellanic Cloud variables. Additionally, a new pulsation diagnostics method reveals that Large Magellanic Cloud variables can be separated into two groups with different evolutionary properties. Our findings suggest that Fornax and Sculptor dwarf spheroidals have undergone different chemical enrichment histories.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
G. Clementini, V. Ripepi, A. Garofalo, R. Molinaro, T. Muraveva, S. Leccia, L. Rimoldini, B. Holl, G. Jevardat de Fombelle, P. Sartoretti, O. Marchal, M. Audard, K. Nienartowicz, R. Andrae, M. Marconi, L. Szabados, D. W. Evans, I. Lecoeur-Taibi, N. Mowlavi, I. Musella, L. Eyer
Summary: This study uses RR Lyrae stars as tracers of the oldest stars and as standard candles for distance measurements. The Gaia DR3 publishes a catalogue of these stars, which is validated and characterized using a specific pipeline. The resulting catalogue is the largest and most parameter-rich of all-sky RR Lyrae stars published so far.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
J. -C. Bouret, F. Martins, D. J. Hillier, W. L. F. Marcolino, H. J. Rocha-Pinto, C. Georgy, T. Lanz, I. Hubeny
Summary: The study focuses on the evolutionary and physical properties of evolved O stars in the Small Magellanic Cloud, analyzing their UV and optical spectra to investigate rotational mixing efficiency as a function of age, rotation, and global metallicity. The results show that giants are more evolved than dwarfs, with no clear trend of a mass discrepancy. Surface CNO abundances are consistent with nucleosynthesis from the CNO cycle, and more evolved objects show stronger chemical evolution. Models including rotation generally reproduce surface abundances and rotation rates, with some objects requiring stronger braking and/or more efficient mixing.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
E. Marini, F. Dell'Agli, M. Di Criscienzo, D. A. Garcia-Hernandez, P. Ventura, M. A. T. Groenewegen, L. Mattsson, D. Kamath, S. Puccetti, M. Tailo, E. Villaver
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
M. A. T. Groenewegen, A. Nanni, M-R L. Cioni, L. Girardi, R. de Grijs, V. D. Ivanov, M. Marconi, M- Moretti, J. M. Oliveira, M. G. Petr-Gotzens, V Ripepi, J. Th van Loon
ASTRONOMY & ASTROPHYSICS
(2020)
Article
Astronomy & Astrophysics
M. A. T. Groenewegen
ASTRONOMY & ASTROPHYSICS
(2020)
Article
Astronomy & Astrophysics
R. E. Mennickent, G. Djurasevic, I Vince, J. Garces, P. Hadrava, M. Cabezas, J. Petrovic, M. Jurkovic, D. Korcakova, H. Markov
ASTRONOMY & ASTROPHYSICS
(2020)
Article
Astronomy & Astrophysics
E. Plachy, A. Pal, A. Bodi, P. Szabo, L. Molnar, L. Szabados, J. M. Benko, R. I. Anderson, E. P. Bellinger, A. Bhardwaj, M. Ebadi, K. Gazeas, F. -J. Hambsch, A. Hasanzadeh, M. I. Jurkovic, M. J. Kalaee, P. Kervella, K. Kolenberg, P. Mikolajczyk, N. Nardetto, J. M. Nemec, H. Netzel, C. -C. Ngeow, D. Ozuyar, J. Pascual-Granado, B. Pilecki, V. Ripepi, M. Skarka, R. Smolec, A. Sodor, R. Szabo, J. Christensen-Dalsgaard, J. M. Jenkins, H. Kjeldsen, G. R. Ricker, R. Vanderspek
Summary: This study presents the first analysis of Cepheid stars observed by the TESS space mission, detecting various low-amplitude features and signs of nonradial modes in different types of Cepheids.
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
(2021)
Article
Astronomy & Astrophysics
M. A. T. Groenewegen, M. Saberi
Summary: Carbon monoxide is an important molecule in circumstellar envelopes of evolved stars, and the new published CO photodissociation radii have significant differences, but the changes in the size of the CO envelope are generally small.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
M. A. T. Groenewegen
Summary: The second data release of Gaia highlighted a parallax zero-point offset of -0.029 mas linked to quasars, leading to challenges in improving the local distance scale. The recent analysis of Gaia EDR3 revealed a mean parallax zero-point offset of -0.021 mas based on quasars, with a proposed correction method based on ecliptic latitude, G-band magnitude, and color information. The study presented an independent investigation into the spatial and magnitude corrections for parallax offset, showcasing a spatial dependence on quasars and a magnitude dependence on wide binaries, ultimately leading to a correction that aligns observed parallaxes with independent measurements.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Ambra Nanni, Sergio Cristallo, Jacco Th van Loon, Martin A. T. Groenewegen
Summary: The study investigates the impact of metallicity on dust formation process in carbon-rich TP-AGB stars, finding that the models can explain the variation of gas and dust content around C-stars and successfully predict the wind speed of C-stars at different metallicities.
Article
Astronomy & Astrophysics
M. A. T. Groenewegen
Summary: This article investigates the variability properties of different types of stars on the asymptotic giant branch (AGB) and presents some results based on the analysis of light curves and spectral data. The study identifies some tracers of interstellar reddening and determines the dust return rate in the solar neighborhood. Moreover, important data findings and inferences are made regarding infrared scattering. This research is of great significance for understanding stellar evolution and the movement of dust in the universe.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
P. Hadrava, M. Cabezas, G. Djurasevic, J. Garces, S. Y. Gorda, M. Jurkovic, D. Korcakova, H. Markov, R. E. Mennickent, J. Petrovic, I Vince, S. Zharikov
Summary: This study investigates the physical properties and changes in the circumstellar matter of the close binary UU Cas through spectral analysis. The results reveal that the line profiles are strongly influenced by the presence of circumstellar matter, and the variability of Hα emission indicates changes in the circumstellar structure over multiple orbital periods.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
R. E. Mennickent, G. Djurasevic, J. Petrovic, P. Gorrini, F. Burgos, M. Jurkovic, A. M. Magalhaes, D. Schleicher, P. Calderon
Summary: We analyzed 109 years of published photometry and times of minima of the interacting binary RX Cas. The study confirms the increasing orbital period trend and identifies changes in the length of the photometric cycle and shape of the orbital light curve. The variations in the orbital light curve can be explained by changes in the physical properties of the accretion disk.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
M. A. T. Groenewegen
Summary: Multiple systems with known astrometric and spectroscopic orbits can be used to determine their distances directly without assumptions, making them ideal for comparing Gaia data release 3 (GDR3) parallax data. By analyzing non-single star (NSS) data, improved parallaxes can potentially be obtained, which is crucial for studying the parallax zero-point offset (PZPO) and improving the distance scale. A sample of 192 orbital parallax determinations for 186 systems was compiled from the literature, and potential wide binary systems (WBS) were also identified. Out of the 37 WBS candidates found, only 21 objects provided information through NSS analysis, with significantly improved parallaxes compared to the main catalogue.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Monika Jurkovic, Emese Plachy, Laszlo Molnar, Martin A. T. Groenewegen, Attila Bodi, Pawel Moskalik, Robert Szabo
Summary: We presented the results of analyzing Type II and anomalous Cepheids using data from the Kepler K2 mission. The precise light curves of these pulsating variable stars are essential for studying their pulsation details and effects. The analysis included Fourier analysis of the light curves and determining physical parameters through model fitting. The study also compared the stars with evolutionary models and found the presence of period doubling and modulation effects.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
A. Vudragovic, M. Jurkovic
Summary: Photometric calibration of the 60 cm Nedeljkovic telescope with FLI PL 230 CCD camera was conducted using standard stars from the Landolt catalog. 31 fields of standard stars were imaged using Johnson's BVRI filters over three nights in August 2019, with extinction and color correction measured. By comparing calibrated magnitudes to those from the Landolt catalog, an accuracy of 2%-5% for the BVRI magnitudes was achieved.
SERBIAN ASTRONOMICAL JOURNAL
(2021)
Correction
Astronomy & Astrophysics
M. I. Jurkovic
SERBIAN ASTRONOMICAL JOURNAL
(2020)