相关论文: Blazhko Effect in Double Mode Cepheids
More than 1300 variables classified provisionally as first overtone RR Lyrae pulsators in the MACHO variable star database of the Large Magellanic Cloud (LMC) have been subjected to standard frequency analysis. Based on the remnant power in…
Context. RR Gem is one of the few Blazhko RR Lyrae that has photometric observations available extended enough to study the long-term courses of its pulsation and modulation properties in detail. Aims. We investigate the pulsation and…
In order to benefit from the 4-year unprecedented precision of the Kepler data, we extracted light curves from the pixel photometric data of the Kepler space telescope for 15 Blazhko RR Lyrae stars. For collecting all the flux from a given…
Classical Cepheid stars that pulsate in the first overtone radial mode often exhibit additional periodicities at the millimagnitude level. Extensive studies of the OGLE data of the Magellanic Clouds have revealed distinct groups based on…
In this paper it is shown that the mathematical form which most precisely describes the Blazhko RR Lyrae light curves is connected to almost periodic functions and not to the mathematics of modulation. That is, the Blazhko effect is more…
Recent photometric observations of first-overtone classical Cepheids and RR Lyrae stars have led to the discovery of additional frequencies showing a characteristic period ratio of 0.60-0.65 with the main pulsation mode. In a promising…
Periodic modulations are seen in normal period pulsars ($P >$ 0.1 sec) over timescales ranging from a few seconds to several minutes. Such modulations have usually been associated with the phenomenon of subpulse drifting. A number of recent…
This paper considers a nonlinear coupling between a radial and a nonradial mode of nearly the same frequency. The results may be of general interest, but in particular have application to the "beating-modes model" of the Blazhko effect…
The photometric observations from the recent decade revolutionized our view on classical pulsators. Low-amplitude signals have been detected photometrically in addition to the dominant high-amplitude radial mode pulsations in many RR Lyrae…
The long-term behaviours of the pulsation and Blazhko periods of RR Lyr are investigated by means of Kepler and ground-based observations. The difficulties in detecting additional modes in the Cepheids monitored with CoRoT are discussed.
Recent theoretical and observational findings breathed new life into the field of RR Lyrae stars. The ever more precise and complete measurements of the space asteroseismology missions revealed new details, such as the period doubling and…
We briefly summarize the BRITE observations of classical Cepheids. Possible detection of modulation in a fundamental mode Cepheid, T Vul, and of additional non-radial modes in first overtone Cepheids, DT Cyg and V1334 Cyg, are reported.
We found a possible relationship between the modulation period and the amplitude of the Blazhko RR Lyrae stars: long modulation period generally implies high modulation amplitude while the short modulation period results in small amplitude.…
New results on the behavior of the double-mode RR Lyrae V338 Boo are presented. The Transiting Exoplanet Survey Satellite (TESS) observed this star again in 2022, and an observing campaign of the American Association of Variable Star…
We report the discovery of periodic modulation of pulsation in 51 fundamental mode classical Cepheids of the Magellanic Clouds observed by the Optical Gravitational Lensing Experiment. Although the overall incidence rate is very low, about…
Classical Cepheids are not only excellent standard candles, but also invaluable tools to test stellar evolution and pulsation theories. Rates of their pulsation period change, quantified usually through $O-C$ diagrams, can be confronted…
We have carried out a study of the orthogonal polarisation mode behaviour as a function of frequency of 18 pulsars, using average pulsar data from the European Pulsar Network (EPN). Assuming that the radiation consists of two 100% polarised…
Known for their large amplitude radial pulsations, classical Cepheids are critical standard candles in astrophysics. However, they also exhibit various pulsational irregularities and additional signals that provide deeper insights into…
The pulsational properties of the Cepheid models along the evolutionary tracks from the Padova group (Girardi et al.), as calculated with our turbulent convective pulsation code, are in good agreement with the resonance constraints imposed…
The numerical hydrodynamic modelling of beat Cepheid behavior has been a longstanding quest in which purely radiative models have failed miserably. We find that beat pulsations occur naturally when turbulent convection is accounted for in…