Wave-like dark matter made of spin-1 particles (dark photons) is expected to form ground state clumps called "vector solitons", which can have different polarizations. In this work, we consider the interaction photons with photons, expressed as dimension-6 operators, and study electromagnetic radiation that arises from an isolated vector soliton due parametric resonant amplification ambient fie...

Collective variables describing the dipole and the quadrupole oscillations of the system of charged particles are introduced, and their equations of motion are analyzed in the presence of a constant magnetic field. The magnetic field causes shifts and splittings of the characteristic frequencies of the collective oscillations. In the neighborhood of these frequencies, parametric resonance occur...

The formation of beam halos has customarily been described in terms of a particle-core model in which the space-charge field of the oscillating core drives particles to large amplitudes. This model involves parametric resonance and predicts a hard upper bound to the orbital amplitude of the halo particles. We show that the presence of colored noise due to space-charge fluctuations and/or machin...

The Van der Pol Mathieu equation, combining self-excitation and parametric excitation, is analysed near and at 1 : 2 resonance, using the averaging method. We analytically prove the existence of stable and unstable periodic solutions near the parametric resonance frequency. Above a certain detuning threshold, quasiperiodic solutions arise with basic periods of order 1 and order 1/ε where ε is t...