Related papers: Helioseismic limit on heavy element abundance
Minor ions in the solar corona are heated to extreme temperatures, far in excess of those of the electrons and protons that comprise the bulk of the plasma. These highly non-thermal distributions make minor ions sensitive probes of the…
Recent solar photospheric abundance analyses have led to a significant reduction of the metal abundances compared to the previous determinations. The solar models computed with standard opacities and diffusion processes using these new…
Solar flare electron acceleration is an efficient process, but its properties (mechanism, location) are not well constrained. Via hard X-ray (HXR) emission, we routinely observe energetic electrons at the Sun, and sometimes we detect…
The solar interior has been scrutinized by two different and independent probes during the last twenty years with important revisions of the solar model, including a recent heavy element abundance revision. Today, we get a quantitatively…
The observed deficit of $\rm ^8B$ solar neutrinos may call for an improved standard model of the sun or an expanded standard model of particle physics ({\it e.g.,} with neutrino masses and mixing). In the former case, contemporary fluid…
We have reanalyzed SUMER observations of a parcel of coronal gas using new collisional ionization equilibrium (CIE) calculations. These improved CIE fractional abundances were calculated using state-of-the-art electron-ion recombination…
The oscillations of a spherical body consisting of hot electron-nuclear plasma are considered. It is shown that there are two basic modes of oscillations. The estimation of the main frequencies of the solar core oscillation gives a…
The hot solar corona exists because of the balance between radiative and conductive cooling and some counteracting heating mechanism which remains one of the major puzzles in solar physics. The coronal thermal equilibrium is perturbed by…
The solar metallicity issue is a long-lasting problem of astrophysics, impacting multi- ple fields and still subject to debate and uncertainties. While spectroscopy has mostly been used to determine the solar heavy elements abundance,…
The first adiabatic exponent profile, noted $\Gamma_1$, computed along adiabatic coordinates $(T, \rho)$ is in the focus of our study. Under conditions of almost fully ionized hydrogen and helium, the $\Gamma_1$ profile is quite sensitive…
It is well established that elemental abundances vary in the solar atmosphere and that this variation is organized by first ionization potential (FIP). Previous studies have shown that in the solar corona low-FIP elements, such as Fe, Si,…
A likely candidate mechanism to heat the solar corona and solar wind is low-frequency "Alfv\'enic" turbulence sourced by magnetic fluctuations near the solar surface. Depending on its properties, such turbulence can heat different species…
Context. The Sun acts as a cornerstone of stellar physics. Thanks to spectroscopic, helioseismic and neutrino flux observations, we can use the Sun as a laboratory of fundamental physics in extreme conditions. The conclusions we draw are…
Heavy element and helium diffusion are both included for the first time in this series of papers on precise solar models, along with improvements in the input data for nuclear reaction rates, the solar luminosity, the solar age, heavy…
Helioseismology has revealed the internal density and rotation profiles of the Sun. Yet, knowledge of its magnetic fields and meridional circulation is confined much closer to the surface, and latitudinal entropy gradients are below…
Normal modes are coupled by the presence of perturbations in the Sun, providing a novel and under-appreciated helioseismic technique with which to image the solar interior. The process of measuring coupling between normal modes is…
Abundances of elements comprising solar energetic particles (SEPs) come with two very different patterns. Historically called "impulsive" and "gradual" events, they have been studied for 40 years, 20 years by the Wind spacecraft. Gradual…
Observations of the Sun in the visible spectral range belong to standard measurements obtained by instruments both on the ground and in the space. Nowadays, both nearly continuous full-disc observations with medium resolution and dedicated…
Helioseismology provides a powerful tool to explore the deep interior of the Sun: for example, the adiabatic sound speed can be inferred with an accuracy of a few parts in 10,000. This has become a serious challenge to theoretical models of…
In this paper, we examine a new updated solar model taking advantage of recent reexamination of the nuclear reactions rates and of the microscopic diffusion of helium and heavy elements. Our best model fits the helioseismic data reasonably…