Aims.We investigate the influence of longitudinal structuring of the surrounding corona on the modes of oscillation of a coronal magnetic flux tube. Methods: .A partial differential equation is derived for the total pressure perturbation of the fast modes and it is solved analytically in terms of Bessel functions, obtaining a dispersion relation

Context: .Compact groups are associations of a few galaxies in which the environment plays an important role in galaxy evolution. The low group velocity dispersion favors tidal interactions and mergers, which may bring stars from galaxies to the diffuse intragroup light. Numerical simulations of galaxy clusters in hierarchical cosmologies show that

We present the first redundant detection of sporadic impact flashes on the Moon from a systematic survey performed between 2001 and 2004. Our wide-field lunar monitoring allows us to estimate the impact rate of large meteoroids on the Moon as a function of the luminous energy received on Earth. It also shows that some historical well-documented

In the present work we show robust indications of the existence of g modes in the Sun using 10 years of GOLF data. The present analysis is based on the exploitation of the collective properties of the predicted low-frequency (25 to 140 microHz) g modes: their asymptotic nature, which implies a quasi equidistant separation of their periods for a

In the present work we describe the formalism necessary to derive the properties of dark matter halos beyond 2 virial radii using the spherical collapse model (without shell crossing) and provide the framework for the theoretical prediction presented by Prada et al. We show in detail how to obtain within this model the probability distribution for

The spectral analyser of the Visible light Imager and Magnetograph (VIM) is a critical device whose concept is dependent on scientific requirements and technical trade-offs, which are directly driven by the nature of the mission. Here, we report on the choices that were made to fulfill the scientific needs, while constantly keeping an eye on