This website requires JavaScript.

Magnetic field spectral evolution in the inner heliosphere

Nikos SioulasZesen HuangChen Shi ...+22 A. Fedorov
Sep 2022
摘要
The radial evolution of the magnetic field fluctuations spectral index andits dependence on plasma parameters is investigated using a merged Parker SolarProbe ($PSP$) and Solar Orbiter ($SO$) dataset covering heliocentric distancesbetween $0.06 ~ \lesssim R ~\lesssim 1$ au. The spectrum is studied as afunction of scale, normalized to the radially dependent ion inertial scale$d_{i}$. In the vicinity of the Sun, the magnetic spectrum inertial range islimited with a power law exponent $\alpha_{B}$ consistent with theIroshnikov-Kraichman phenomenology of Alfv\'enic turbulence, $\alpha_{B} =-3/2$, independent of plasma parameters. The inertial range of turbulence growswith distance from the Sun, progressively extending to larger spatial scales,while at the same time steepening towards a Kolomogorov scaling, with a meanvalue of $\alpha_{B} =-5/3$. Highly alfv\'enic intervals seem to retain theirnear-Sun scaling and only show a minor steepening with distance. In contrast,intervals, where turbulence is characterized by large magnetic energy excessand no dominance of outwardly propagating Alfv\'enic fluctuations, appear tohave spectra that steepen significantly with distance from the Sun, resultingin slightly anomalously steep inertial range slopes at $1~au$. Thoughgenerically slower solar wind streams exhibit steeper spectra, the correlationcan be attributed to the underlying positive correlation between solar windspeed and alfv\'enicity, i.e. to the relatively rare occurrence of highlyAlfv\'enic slow wind.
展开全部
图表提取

暂无人提供速读十问回答

论文十问由沈向洋博士提出,鼓励大家带着这十个问题去阅读论文,用有用的信息构建认知模型。写出自己的十问回答,还有机会在当前页面展示哦。

Q1论文试图解决什么问题?
Q2这是否是一个新的问题?
Q3这篇文章要验证一个什么科学假设?
0
被引用
笔记
问答