arXiv subjects

J. J. Gonzalez-Aviles

Publications and source records attributed to J. J. Gonzalez-Aviles.

5 recordsLinked to original sources

arXiv2025

Global CME-driven oscillations in the outer solar corona

Coronal mass ejections (CMEs) are known drivers of large-scale waves in the low corona. However, wave dynamics in the extended corona and inner heliosphere remain largely unexplored. Here, we report the first observational and numerical evidence of coherent global compressive oscillations in the outer corona and inner heliosphere, revealed by white-light SOHO/LASCO C3 data and an MHD simulation. Analyzing the CME event of 2012 July 23 using Spectral Proper Orthogonal Decomposition (SPOD), we isolate two distinct wave signatures: (1) a directional fast-mode shock-like compressive wave that dissipates completely within ~3 hours, and (2) a large-scale global circular wavefront consistent with fast-mode MHD behavior, lasting ~7 hours and extending across the LASCO C3 field of view, marking the first detection of such a global oscillation. Our findings reveal a previously unrecognized component of CME-driven wave activity, providing new constraints on the dynamics of the extended corona and inner heliosphere.

astro-ph.SR↗

arXiv2015

Newtonian CAFE: a new ideal MHD code to study the solar atmosphere

We present a new code designed to solve the equations of classical ideal magneto-hydrodynamics (MHD) in three dimensions, submitted to a constant gravitational field. The purpose of the code centers on the analysis of solar phenomena within the photosphere-corona region. We present 1D and 2D standard tests to demonstrate the quality of the numerical results obtained with our code. As solar tests we present the transverse oscillations of Alfvenic pulses in coronal loops using a 2.5D model, and as 3D tests we present the propagation of impulsively generated MHD-gravity waves and vortices in the solar atmosphere. The code is based on high-resolution shock-capturing methods, uses the HLLE flux formula combined with Minmod, MC and WENO5 reconstructors. The divergence free magnetic field constraint is controlled using the Flux Constrained Transport method.

astro-ph.SR↗

arXiv2015

Estimating the contribution of Alfvén waves to the process of heating the quiet solar corona

We solve numerically the ideal MHD equations with an external gravitational field in 2D in order to study the effects of impulsively generated linear and non-linear Alfvén waves into isolated solar arcades and coronal funnels. We analyze the region containing the interface between the photosphere and the corona. The main interest is to study the possibility that Alfvén waves triggers the energy flux transfer toward the quiet solar corona and heat it, including the case that two consecutive waves can occur. We find that in the case of arcades, short or large, the transferred fluxes by Alfvén waves are sufficient to heat the quiet corona only during a small lapse of time and in a certain region. In the case of funnels the threshold is achieved only when the wave is faster than 10 km/s, which is extremely high. We conclude from our analysis, that Alfvén waves, even in the optimistic scenario of having two consecutive Alfvén wave pulses, cannot transport enough energy as to heat the quiet corona.

astro-ph.SR↗

arXiv2013

Rotation curves of rotating galactic BEC dark matter halos

We present the dynamics of rotating Bose Condensate galactic dark matter halos, made of an ultralight spinless boson. We restrict to the case of adding axisymmetric rigid rotation to initially spherically symmetric structures and show there are three regimes: i) small angular momentum, that basically retains the drawbacks of spherically symmetric halos related to compactness and failure at explaining galactic RCs, ii) an intermediate range of values of angular momentum that allow the existence of long-lived structures with acceptable RC profiles, and iii) high angular momentum, in which the structure is dispersed away by rotation. We also present in detail the new code used to solve the Gross-Pitaevskii Poisson system of equations in three dimensions.

astro-ph.CO↗

arXiv2013

Stability of BEC galactic dark matter halos

In this paper we show that spherically symmetric BEC dark matter halos, with the $\sin r/r$ density profile, that accurately fit galactic rotation curves and represent a potential solution to the cusp-core problem are unstable. We do this by introducing back the density profiles into the fully time-dependent Gross-Pitaevskii-Poisson system of equations. Using numerical methods to track the evolution of the system, we found that these galactic halos lose mass at an approximate rate of half of its mass in a time scale of dozens of Myr. We consider this time scale is enough as to consider these halos are unstable and unlikely to be formed. We provide some arguments to show that this behavior is general and discuss some other drawbacks of the model that restrict its viability.

astro-ph.CO↗