相关论文: Amplitude Saturation in Beta Cephei Models
The influence of oscillatory perturbations on autonomous strongly nonlinear systems in the plane is investigated. It is assumed that the intensity of perturbations decays with time, and their frequency increases according to a power law.…
We report a multisite photometric campaign for the Beta Cephei star 12 Lacertae. 750 hours of high-quality differential photoelectric Stromgren, Johnson and Geneva time-series photometry were obtained with 9 telescopes during 190 nights.…
We develop the effective non-Hermitian Hamiltonian approach for open systems with Neumann boundary conditions. The approach can be used for calculating the scattering matrix and the scattering function in open resonator-waveguide systems.…
Analysis of the \textit{Kepler} $\delta$\,Sct star KIC\,7106205 showed amplitude modulation in a single pressure mode, whilst all other pressure and gravity modes remained stable in amplitude and phase over the 1470\,d length of the…
We experimentally and theoretically investigate the lowest-lying axial excitation of an atomic Bose-Einstein condensate in a cylindrical box trap. By tuning the atomic density, we observe how the nature of the mode changes from a…
Systematic search for multiperiodicity in the LMC Cepheids (Moskalik, Kolaczkowski & Mizerski 2004) has led to discovery of low amplitude nonradial modes in a substantial fraction of overtone pulsators. We present detailed discussion of…
The most puzzling aspect of the radio emission from LSI+61303 is that the large periodic radio outburst, with period equal to the orbital one, occurs very displaced from periastron passage, nearly at apoastron. In 1992, Taylor, one of the…
The peaked-spectrum (PS) sources exhibit turnover characteristics in their broad radio spectra. However, the mechanism underlying this phenomenon remains elusive. The two most common hypotheses are synchrotron self-absorption (SSA) and…
Beta oscillations observed in motor cortical local field potentials (LFPs) recorded on separate electrodes of a multi-electrode array have been shown to exhibit non-zero phase shifts that organize into a planar wave propagation. Here, we…
We present a seismic study of $\delta$ Scuti based on a mode identification from multicoulor photometry. The dominant frequency can be associated only with a radial mode and the second frequency is, most probably, a dipole mode. The other…
The recently discovered phenomenon of nonlinear supratransmission consists in a sudden increase of the amplitude of a transmitted wave triggered by the excitation of nonlinear localized modes of the medium. We examine this process for the…
p-mode oscillations in solar-like stars are excited by the outer convection zone in these stars and reflected close to the surface. The p-modes are trapped inside an acoustic cavity, but the modes only stay trapped up to a given frequency…
We report the detection of 15 GHz radio continuum emission associated with the classical Cepheid variable star delta Cephei based on observations with the Karl G. Jansky Very Large Array. Our results constitute the first probable detection…
We excite the lowest-lying quadrupole mode of a Bose-Einstein condensate by modulating the atomic scattering length via a Feshbach resonance. Excitation occurs at various modulation frequencies, and resonances located at the natural…
We study theoretically the existence of bulk and surface discrete breathers in a one-dimensional magnetic metamaterial comprised of a periodic binary array of split-ring resonators. The two types of resonators differ in the size of their…
The self-modulation (SM) instability transforms a long charged particle bunch traveling in plasma into a train of microbunches that resonantly drives large-amplitude wakefields. We present the first determination of the saturation length of…
In this work, we develop machine learning techniques to study nonperturbative scattering amplitudes. We focus on the two-to-two scattering amplitude of identical scalar particles, setting the double discontinuity to zero as a simplifying…
We present a solution for the scattered field caused by an incident wave interacting with an infinite cascade of blades with complex boundary conditions. This extends previous studies by allowing the blades to be compliant, porous or…
Context: The Circular Restricted Three-Body Problem provides a fundamental framework for understanding resonant dynamics in binary star systems. Aims: We develop a unified Hamiltonian formulation for mean-motion resonances that encompasses…
We present the results of a spectroscopic multisite campaign for the beta Cephei star 12 (DD) Lacertae. Our study is based on more than thousand high-resolution high S/N spectra gathered with 8 different telescopes in a time span of 11…