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Related papers: Blazhko Effect in Double Mode Cepheids

200 papers

An optoelectronic oscillator exhibiting a large delay in its feedback loop is studied both experimentally and theoretically. We show that multiple square-wave oscillations may coexist for the same values of the parameters…

Optics · Physics 2015-01-14 Lionel Weicker , Thomas Erneux , David P. Rosin , Daniel J. Gauthier

Polarization behaviour shows a transition in the pulsar population, where energetic sources with higher spin-down energy loss, $\dot{E} > 10^{34}$ erg~s$^{-1}$, often have fractional linear polarisation ($L/I$) close to 100\%, while below…

High Energy Astrophysical Phenomena · Physics 2025-05-20 Dipanjan Mitra , Rahul Basu , George I. Melikidze

We have frequency analyzed 6391 variables classified earlier as fundamental mode RR Lyrae (RR0) stars in the MACHO database on the Large Magellanic Cloud (LMC). The overwhelming majority of these variables have been proved to be indeed RR0…

Plasmon modes of a two-dimensional lattice of long conducting circular wires are investigated by using an embedding technique to solve Maxwell's equations rigorously. The frequency-dependent density of states is calculated for various…

Materials Science · Physics 2007-05-23 J. M. Pitarke , J. E. Inglesfield , N. Giannakis

We report the discovery of eleven beat Cepheids in the Small Magellanic Cloud, using data obtained by the EROS microlensing survey. Four stars are beating in the fundamental and first overtone mode (F/1OT), seven are beating in the first…

After a brief historical introduction and recalling basic concepts of stellar oscillation theory, I focus my review on interpretation of secondary periodicities found in RR Lyrae stars and Cepheids as a manifestation of nonradial mode…

Solar and Stellar Astrophysics · Physics 2016-06-15 W. A. Dziembowski

Almost half of all classical Cepheids do not pulsate in fundamental mode, and nowadays, the fundamentalization of their higher-mode periods is frequently applied to increase the sample size in astrophysical investigations and allow for…

Solar and Stellar Astrophysics · Physics 2024-06-28 Bogumił Pilecki

Properties of single-pulse and two-pulse echoes and their secondary echo signals as well as the role of reversible relaxation in the observed decays of echo signals at the multipulse excitation mode in a number of multidomain magnetic…

Materials Science · Physics 2007-05-23 A. Akhalkatsi , T. Gegechkori , G. Katalandze , G. Mamniashvili , Z. Shermadini

Following the paper of K. Shimizu et al. (2011) we consider the Bonhoeffer-van der Pol oscillator with non-autonomous periodic perturbation. We show that the presence of mixed mode oscillations reported in that paper can be explained using…

Mathematical Physics · Physics 2013-11-21 E. Kutafina

This is a part of an overview of my early studies on nonlinear spin-phonon dynamics in solid state optical-wavelength phonon lasers (phasers) started in 1984. The main goal of this work is a short description and a qualitative analysis of…

Optics · Physics 2011-01-04 D. N. Makovetskii

We present the analysis of four first overtone RR Lyrae stars observed with the Kepler space telescope, based on data obtained over nearly 2.5yr. All four stars are found to be multiperiodic. The strongest secondary mode with frequency f_2…

We argue, following our earlier works (the "CEBZMC model"), that the phenomenon of twin peak high frequency quasi-periodic oscillations (QPOs) observed in black hole X-ray binaries is caused by magnetic coupling (MC) between accretion disk…

Astrophysics · Physics 2008-11-26 Ding-Xiong Wang , Yong-Chun Ye , Chang-Yin Huang

The observations of the photometric space telescopes CoRoT and Kepler show numerous Blazhko RR Lyrae stars which have non-repetitive modulation cycles. The phenomenon can be explained by multi-periodic, stochastic or chaotic processes. From…

Solar and Stellar Astrophysics · Physics 2013-07-15 J. M. Benkő , M. Paparó

The MACHO variables of LMC Field 77 that lie in the vicinity of the Cepheid instability strip are reexamined. Among the 144 variables that we identify as Cepheids we find 14 that have Fourier amplitudes <0.05 mag in the MACHO red band, of…

Astrophysics · Physics 2009-11-11 J. Robert Buchler , Peter R. Wood , Stefan Keller , Igor Soszynski

Physical and phenomenological properties (radius, luminosity, shape of the light curve, etc.) of Cepheids strongly depend on the pulsation period, with the exception of the pulsation amplitude. A possible factor causing a wide range of…

Solar and Stellar Astrophysics · Physics 2012-01-13 László Szabados , Péter Klagyivik

The discovery of $\beta$ Cephei stars in low metallicity environments, as well as the difficulty in theoretically explaining the excitation of the pulsation modes observed in some $\beta$ Cephei and hybrid SPB-$\beta$ Cephei pulsators,…

Astrophysics · Physics 2008-11-26 A. Miglio , J. Montalban , M. -A. Dupret

Effects of rotational mode coupling on photometric parameters of stellar oscillations are studied. At moderate rotation rates, a strong coupling between modes of spherical harmonic degree, $\ell$, differing by 2 and of the same azimuthal…

Standard weak coupling methods are used to study collective modes in the superconducting state of a double-layer system with intralayer and interlayer interaction, as well as a Josephson-type coupling and single particle hopping between the…

Condensed Matter · Physics 2009-10-28 F. Forsthofer , S. Kind , J. Keller

Recent photometric space missions, such as CoRoT and Kepler revealed that many RR Lyrae stars pulsate -- beyond their main radial pulsation mode -- in low amplitude modes. Space data seem to indicate a clear trend, namely overtone (RRc)…

Solar and Stellar Astrophysics · Physics 2015-08-19 J. M. Benkő , R. Szabó

Using the novel data set of the MACHO project, we show that three ``Blazhko Effect'' RR Lyrae stars show nearly-pure amplitude modulation of a single pulsation mode. This is strong observational evidence that the ``Oblique Pulsator Model''…