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Context.The heating of the solar corona and solar wind, particularly through suprathermal particles and kinetic Alfvén waves (KAWs) within the 0–10 RSunrange, has been a subject of great interest for many decades. This study investigates and explores the acceleration and heating of charged particles and the role of KAWs in the solar corona. Aims.We investigate how KAWs transport energy and accelerate and heat the charged particles, focusing on the behavior of perturbed electromagnetic (EM) fields, the Poynting flux vectors, net power transfer through the solar flux loop tubes, resonant particles’ speed, group speed, and the damping length of KAWs. The study examines how these elements are influenced by suprathermal particles (κ) and the electron-to-ion temperature ratios (Te/Ti). Methods.We used kinetic plasma theory coupled with the Vlasov-Maxwell model to investigate the dynamics of KAWs and particles. We assumed a collisionless, homogeneous, and low-beta electron-ion plasma in which Alfvén waves travel in the kinetic limits; that is,me/mi ≪ β ≪ 1. Furthermore, the plasma incorporates suprathermal high-energy particles, necessitating an appropriate distribution function to accurately describe the system. We adopted the Kappa distribution function as the most suitable choice for our analysis. Results.The results show that the perturbed EM fields are significantly influenced byκand the effect of Te/Ti. We evaluate both the parallel and perpendicular Poynting fluxes and find that the parallel Poynting flux (Sz) dissipates gradually for lowerκvalues. In contrast, the perpendicular flux (Sx) dissipates quickly over shorter distances. Power deposition in solar flux tubes is significantly influenced byκand Te/Ti. We find that particles can heat the solar corona over long distances (RSun) in the parallel direction and short distances in the perpendicular direction. The group velocity of KAWs increases for lowerκvalues, and the damping length, LG, is enhanced under lowerκ, suggesting longer energy transport distances (RSun). These findings offer a comprehensive understanding of particle-wave interactions in the solar corona and wind, with potential applications for missions such as the Parker Solar Probe, (PSP), and can also apply to other environments where non-Maxwellian particle distributions are frequently observed.more » « lessFree, publicly-accessible full text available February 1, 2026
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Abstract The soil mantle of the tropical karstic landscapes of Southern Mexico was shaped by specific processes of pedogenesis and long‐term human impacts of ancient Maya agriculture. To understand the interaction between natural and human‐induced soil‐forming processes in the calcareous mountains of Chiapas state, we studied soil toposequences around the Classic Maya site of Budsilhá and related them to the archaeological evidence of settlement and land‐use distribution. Soil chemical analysis, micromorphological observations, and clay mineral identification were carried out in key soil profiles at the main geoforms. Limestone hills are occupied by shallow Rendolls which are usually perceived as incipient soils. However, high content of silicate clay composed of kaolinite and vermiculite and ferruginous clayey soil material observed at macro‐ and microscale backed the hypothesis that these soils were formed from the residues of thick Terra Rossa after their erosion. Swampy lowlands are occupied by thick clayey gleyic soils with clay mineral assemblages similar to those in the upland Rendolls. We suppose that the mineral matrix of the lowland soils is largely derived from the pedosediments of eroded upland Terra Rossa, which lost original ferruginous pigmentation and aggregation due to redoximorphic processes. Some wetland soils contain neoformed gypsum that is atypical for humid tropics; sulfide‐sulfate transformation under fluctuating redox conditions could promote gypsum synthesis. Ancient Maya land use was closely related to soil‐geomorphic conditions: settlements with homegardens occupied calcareous hills, whereas the primary agricultural domain was developed on lowland soils after their drainage by artificial canals.more » « less
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