Search Publications
Testing ultralow amplitude Cepheid candidates in the Galactic disk by TESS and Gaia
Bódi, Attila; Szabó, Róbert; Molnár, László +1 more
Ultralow amplitude (ULA) and strange mode Cepheids are thought to be pulsating variable stars that are near to or are at the edges of the classical instability strip. Until now, a few dozen such variable star candidates have been found both in the Large Magellanic Cloud and the Milky Way. For the present work, we studied six ULA Cepheid candidates…
Frequency analysis of the hybrid δ Sct-γ Dor star CoRoT-102314644
Creevey, O. L.; Pichon, B.; Sánchez Arias, J. P. +1 more
Context. Observations from space missions allowed significant progress due to the absence of atmospheric noise contributions and having uninterrupted data sets. This has been extremely beneficial in asteroseismology because many oscillation frequencies, not observable from the ground, can be detected. One example of this success is the large numbe…
Pulsational instability of pre-main-sequence models from accreting protostars. I. Constraining the input physics for accretion with spectroscopic parameters and stellar pulsations
Zwintz, K.; Barnes, T. G.; Steindl, T. +2 more
Context. The picture of pre-main-sequence evolution is often simplified by the application of classical initial models. Such models have large initial radii and sufficient uniform contraction to make them fully convective, however, real stars are born as small protostellar seeds in collapsing molecular clouds and obtain their final mass by means o…
Improving transit characterisation with Gaussian process modelling of stellar variability
Cabrera, J.; Barros, S. C. C.; Santos, N. C. +4 more
Context. New photometric space missions to detect and characterise transiting exoplanets are focusing on bright stars to obtain high cadence, high signal-to-noise light curves. Since these missions will be sensitive to stellar oscillations and granulation even for dwarf stars, they will be limited by stellar variability. Therefore, it is crucial a…
Transport of angular momentum by stochastically excited waves as an explanation for the outburst of the rapidly rotating Be star HD49330
Neiner, C.; Lee, U.; Mathis, S. +3 more
Context. HD 49330 is an early Be star that underwent an outburst during its five-month observation with the CoRoT satellite. An analysis of its light curve revealed several independent p and g pulsation modes, in addition to showing that the amplitude of the modes is directly correlated with the outburst.
Aims: We modelled the results obtaine…
Is the primary CoRoT target HD 43587 under a Maunder minimum phase?
Barbosa, R.; do Nascimento, J. -D.; Castro, M. +4 more
Context. One of the most enigmatic phenomena related to solar activity is the so-called Maunder minimum phase. It consists in the lowest sunspot count ever registered for the Sun and has not been confirmed for other stars to date. Since the spectroscopic observations of stellar activity at the Mount Wilson Observatory, the solar analog HD 43587 ha…
Transiting exoplanets from the CoRoT space mission. XXIX. The hot Jupiters CoRoT-30 b and CoRoT-31 b
Mazeh, T.; Aigrain, S.; Alonso, R. +31 more
Aims: We report the discovery as well as the orbital and physical characterizations of two new transiting giant exoplanets, CoRoT-30 b and CoRoT-31 b, with the CoRoT space telescope.
Methods: We analyzed two complementary data sets: photometric transit light curves measured by CoRoT, and radial velocity curves measured by the HARPS spect…
Spot evolution in the eclipsing binary CoRoT 105895502
Schmitt, J. H. M. M.; Czesla, S.; Wichmann, R. +1 more
Stellar activity is ubiquitous in late-type stars. The special geometry of eclipsing binary systems is particularly advantageous to study the stellar surfaces and activity. We present a detailed study of the 145 d CoRoT light curve of the short-period (2.17 d) eclipsing binary CoRoT 105895502. By means of light-curve modeling with Nightfall, we de…
CSI 2264: Simultaneous optical and X-ray variability in the pre-main sequence stars of NGC 2264. II. Photometric variability, magnetic activity, and rotation in class III objects and stars with transition disks
Micela, G.; Stauffer, J.; Sciortino, S. +6 more
Context. Pre-main sequence stars are variable sources. In diskless stars this variability is mainly due to the rotational modulation of dark photospheric spots and active regions, as in main sequence stars even if associated with a stronger magnetic activity.
Aims: We aim at analyzing the simultaneous optical and X-ray variability in these st…
Forward seismic modeling of the pulsating magnetic B-type star HD 43317
Aerts, C.; Neiner, C.; Mathis, S. +5 more
The large-scale magnetic fields detected at the surface of about 10% of hot stars extend into the stellar interior, where they may alter the structure. Deep inner regions of stars are only observable using asteroseismology. Here, we investigate the pulsating magnetic B3.5V star