相关论文: Coronal turbulence and the angular broadening of r…
Treatments of the radio scattering due to density turbulence in the solar wind typically employ asymptotic approximations to the phase structure function. We use a general structure function (GSF) that straddles the asymptotic limits and…
The angular broadening of compact radio sources observed through a medium having turbulent density irregularities is usually estimated using the phase structure function. We employ an exact formulation for the phase structure function that…
Angular broadening observations of compact radio sources provide a powerful method for probing the solar corona and solar wind. Such observations enable studies of the phase structure function, turbulence amplitude, intermediate-scale…
The fine structures of solar radio bursts reveal complex dynamics in the corona, yet the observed characteristics of these sub-second bursts are additionally complicated by radio wave scattering in the turbulent solar corona. We examine the…
Solar radio bursts are strongly affected by radio-wave scattering on density inhomogeneities, changing their observed time characteristics, sizes, and positions. The same turbulence causes angular broadening and scintillation of galactic…
We seek to reconcile observations of small source sizes in the solar corona at 327 MHz with predictions of scattering models that incorporate refractive index effects, inner scale effects and a spherically diverging wavefront. We use an…
Low frequency radio wave scattering and refraction can have a dramatic effect on the observed size and position of radio sources in the solar corona. The scattering and refraction is thought to be due to fluctuations in electron density…
Solar radio observations provide a unique diagnostic of the outer solar atmosphere. However, the inhomogeneous turbulent corona strongly affects the propagation of the emitted radio waves, so decoupling the intrinsic properties of the…
Electromagnetic wave scattering off density inhomogeneities in the solar corona is an important process which determines both the apparent source size and the time profile of radio bursts observed at 1 AU. Here we model the scattering…
We present a turbulence index independent framework for simultaneously deriving solar wind velocity and coronal electron density in the near-Sun region using the spectral broadening of spacecraft radio signals. The formulation accommodates…
Metric and decametric radio-emissions from the Sun are the only direct source of information about the dynamics of non-thermal electrons in the upper corona. In addition, the combination of spectral and imaging (sizes, shapes, and…
Radio signals propagating via the solar corona and solar wind are significantly affected by compressive waves, impacting properties of solar bursts as well as sources viewed through the turbulent solar atmosphere. While static fluctuations…
Eruptive activity in the solar corona can often lead to the propagation of shock waves. In the radio domain the primary signature of such shocks are type II radio bursts, observed in dynamic spectra as bands of emission slowly drifting…
The observed features of the radio sources indicate complex propagation effects embedded in the waves of solar radio bursts. In this work, we perform ray-tracing simulations on radio wave transport in the corona and interplanetary region…
Metrewave solar type-III radio bursts offer a unique means to study the properties of turbulence across the coronal heights.Theoretical models have shown that the apparent intensity and size of the burst sources evolve at sub-second scales…
One of the most commonly observed solar radio sources in the metric and decametric wavelengths is the solar noise storm. These are generally associated with active regions and are believed to be powered by the plasma emission mechanism.…
The solar corona is a highly-structured plasma which can reach temperatures of more than ~2 MK. At low frequencies (decimetric and metric wavelengths), scattering and refraction of electromagnetic waves are thought to considerably increase…
The structure function is a useful quantity to characterize wavefront distortions. We derive expressions for the structure functions of the averaged wavefront phase and slopes. The expressions are valid within the inertial range of…
Remarkable progress has been made in understanding turbulent astrophysical plasmas in past decades including, notably, the solar wind and the interstellar medium. In the case of the solar wind, much of this progress has relied on in situ…
The spatial-frequency coverage of a radio interferometer is increased by combining samples acquired at different times and observing frequencies. However, astrophysical sources often contain complicated spatial structure that varies within…