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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 R_Sunrange, 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 (T_e/T_i). 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,m_e/m_i ≪ 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 T_e/T_i. We evaluate both the parallel and perpendicular Poynting fluxes and find that the parallel Poynting flux (S_z) dissipates gradually for lowerκvalues. In contrast, the perpendicular flux (S_x) dissipates quickly over shorter distances. Power deposition in solar flux tubes is significantly influenced byκand T_e/T_i. We find that particles can heat the solar corona over long distances (R_Sun) in the parallel direction and short distances in the perpendicular direction. The group velocity of KAWs increases for lowerκvalues, and the damping length, L_G, is enhanced under lowerκ, suggesting longer energy transport distances (R_Sun). 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. 

The recent emergence of Medical Large Vision Language Models (Med-LVLMs) has enhanced medical diagnosis. However, current Med-LVLMs frequently encounter factual issues, often generating responses that do not align with established medical facts. Retrieval-Augmented Generation (RAG), which utilizes external knowledge, can improve the factual accuracy of these models but introduces two major challenges. First, limited retrieved contexts might not cover all necessary information, while excessive retrieval can introduce irrelevant and inaccurate references, interfering with the model’s generation. Second, in cases where the model originally responds correctly, applying RAG can lead to an over-reliance on retrieved contexts, resulting in incorrect answers. To address these issues, we propose RULE, which consists of two components. First, we introduce a provably effective strategy for controlling factuality risk through the calibrated selection of the number of retrieved contexts. Second, based on samples where over-reliance on retrieved contexts led to errors, we curate a preference dataset to fine-tune the model, balancing its dependence on inherent knowledge and retrieved contexts for generation. We demonstrate the effectiveness of RAFE on three medical VQA datasets, achieving an average improvement of 20.8% in factual accuracy. 

A method for detecting low-velocity impact damage in carbon fiber reinforced polymer (CFRP) is presented. It involves the use of the Impulse Excitation Technique (IET) and hysteresis loops to calculate the damping parameter of T700/NCT304-1 carbon/epoxy samples subjected to various low-velocity impact energies. The value of the coefficient of restitution (COR) is determined for each impact, ranging between 0.62 for the lowest impact energy to 0.48 for the highest one. The results reveal that a three-step increase in the damping parameter exists in all cases as the impact energy on the specimen increases. An abrupt jump in the damping parameter value is observed for impact energies exceeding ∼0.9 of the material's maximum capacity. Overall, at the highest impact energy equal to 3.65 J, the damping parameter increased by 43.3% compared to the pristine specimen. Additionally, two cases of cyclic tension-tension loading were applied to the specimens, with maximum stresses set at 150 MPa and 200 MPa. The measured values of plastic and elastic strain energy were used to determine the damping ratios. For both cases, the damping of the specimen subjected to the highest impact energy was ∼1.2 times greater than that of an intact specimen, with an increase pattern similar to the findings of the IET method. Optical microscope images of the specimens are provided to illustrate various damage modes observed in the composite materials. 

Abstract  We present a stochastic field line mapping model where the interplanetary magnetic field lines are described by a density distribution function satisfying a Fokker–Planck equation that is solved numerically. Due to the spiral geometry of the nominal Parker field and to the evolving nature of solar wind turbulence, the heliospheric diffusion of the magnetic field lines is both heterogeneous and anisotropic, including a radial component. The longitudinal distributions of the magnetic field lines are shown to be close to circular Gaussian distributions, although they develop a noticeable skewness. The magnetic field lines emanating from the Sun are found to differ, on average, from the spirals predicted by Parker. Although the spirals remain close to Archimedean, they are here underwound, on average. Our model predicts a spiral angle that is smaller by ∼5° than the Parker spiral angle at Earth’s orbit for the same solar wind speed ofV_sw= 400 km s⁻¹. It also predicts an angular position on the solar disk of the best magnetically connected footpoint to an observer at 1 au that is shifted westward by ∼10° with respect to the Parker’s field model. This significantly changes the angle of the most probable magnetic connection between possible sources on the Sun and observers in the inner heliosphere. The results have direct implications for the heliospheric transport of “scatter-free” electrons accelerated in the aftermath of solar eruptions. 

Abstract A steady-state, semi-analytical model of energetic particle acceleration in radio-jet shear flows due to cosmic-ray viscosity obtained by Webb et al. is generalized to take into account more general cosmic-ray boundary spectra. This involves solving a mixed Dirichlet–Von Neumann boundary value problem at the edge of the jet. The energetic particle distribution functionf₀(r,p) at cylindrical radiusrfrom the jet axis (assumed to lie along thez-axis) is given by convolving the particle momentum spectrum $f_0(\infty ,p\prime )$with the Green’s function $G(r,p;p\prime )$, which describes the monoenergetic spectrum solution in which $f_0\to \delta (p-p\prime )$asr→ ∞ . Previous work by Webb et al. studied only the Green’s function solution for $G(r,p;p\prime )$. In this paper, we explore for the first time, solutions for more general and realistic forms for $f_0(\infty ,p\prime )$. The flow velocityu=u(r)e_zis along the axis of the jet (thez-axis).uis independent ofz, andu(r) is a monotonic decreasing function ofr. The scattering time $\tau {(r,p)={\tau }_0\left(p/p_0\right)}^{\alpha }$in the shear flow region 0 <r<r₂, and $\tau {(r,p)={\tau }_0\left(p/p_0\right)}^{\alpha }{\left(r/r_2\right)}^s$, wheres> 0 in the regionr>r₂is outside the jet. Other original aspects of the analysis are (i) the use of cosmic ray flow lines in (r,p) space to clarify the particle spatial transport and momentum changes and (ii) the determination of the probability distribution ${\psi }_p(r,p;p\prime )$that particles observed at (r,p) originated fromr→ ∞ with momentum $p\prime$. The acceleration of ultrahigh-energy cosmic rays in active galactic nuclei jet sources is discussed. Leaky box models for electron acceleration are described. 

We report the first detection of coherent elastic neutrino-nucleus scattering (CEvNS) on natural germanium, measured at the Spallation Neutron Source at Oak Ridge National Laboratory. The Ge-Mini detector of the COHERENT collaboration employs large-mass, low-noise, high-purity germanium spectrometers, enabling excellent energy resolution, and an analysis threshold of 1.5 keV electron-equivalent ionization energy. We observe an on-beam excess of ${20.6}_{-6.3}^{+7.1}$counts with a total exposure of 10.22 GWhkg, and we reject the no-CEvNS hypothesis with $3.9\sigma$significance. The result agrees with the predicted standard model of particle physics signal rate within $2\sigma$. Published by the American Physical Society2025