English
Related papers

Related papers: On slow solar wind with high Alfv\'enicity: from c…

200 papers

Although the origins of slow solar wind are unclear, there is increasing evidence that at least some of it is released in a steady state on over-expanded coronal hole magnetic field lines. This type of slow wind has similar properties to…

Space Physics · Physics 2020-01-28 D. Stansby , L. Matteini , T. S. Horbury , D. Perrone , R. D'Amicis , L. Berčič

We make use of the Parker Solar Probe (PSP) data to explore the nature of solar wind turbulence focusing on the Alfv\'enic character and power spectra of the fluctuations and their dependence on distance and context (i.e. large scale solar…

Fast and slow solar wind have distinct properties linked to their solar sources.Alfv\'enic slow wind complicates the usual speed-based classification, especially at intermediate speeds. Solar Orbiter's Solar Wind Analyzer (SWA) offers…

The solar wind is highly structured in fast and slow flows. These two dynamical regimes remarkably differ not only for the average values of magnetic field and plasma parameters but also for the type of fluctuations they transport. Fast…

Solar and Stellar Astrophysics · Physics 2017-08-04 R. Bruno , D. Telloni , D. DeIure , E. Pietropaolo

Close to Earth the solar wind is usually super-Alfv\'enic, i.e. the speed of the solar wind is much larger than the Alfv\'en speed. However, in the lower coronal regions, the solar wind is mostly sub-Alfv\'enic. With the Parker Solar Probe…

The $1/f$ noise is a ubiquitous phenomenon in natural systems. Since the advent of space exploration, the $1/f$ range has been consistently observed in \textit{in situ} solar wind measurements throughout the heliosphere, sparking decades of…

Solar and Stellar Astrophysics · Physics 2025-09-03 Zesen Huang , Marco Velli , B. D. G. Chandran , Chen Shi , Yuliang Ding , Lorenzo Matteini , Kyung-Eun Choi

Alfv\'enicity is a well-known property, common in the solar wind, characterized by a high correlation between magnetic and velocity fluctuations. Data from the Parker Solar Probe (PSP) enable the study of this property closer to the Sun…

In the corona, plasma is accelerated to hundreds of kilometers per second, and heated to temperatures hundreds of times hotter than the Sun's surface, before it escapes to form the solar wind. Decades of space-based experiments have shown…

A canonical description of a corotating solar wind high speed stream, in terms of velocity profile, would indicate three main regions:a stream interface or corotating interaction region characterized by a rapid flow speed increase and by…

We identify more than ten steady sub-Alfv\'enic solar wind intervals from the measurements of the Parker Solar Probe (PSP) from encounter 8 to encounter 14. An analysis of these sub-Alfv\'enic intervals reveals similar properties and…

Solar and Stellar Astrophysics · Physics 2023-12-05 Yiming Jiao , Ying D. Liu , Hao Ran , Wenshuai Cheng

New aspects of the slow solar wind turbulent heating and acceleration are investigated. A physical meaning of the lower boundary of the Alfv\'en wave turbulent spectra in the solar atmosphere and the solar wind is studied and the…

Solar and Stellar Astrophysics · Physics 2015-06-04 Bidzina M. Shergelashvili , Horst Fichtner

In the lower solar coronal regions where the magnetic field is dominant, the Alfven speed is much higher than the wind speed. In contrast, the near-Earth solar wind is strongly super-Alfvenic, i.e., the wind speed greatly exceeds the Alfven…

The two-state solar wind paradigm is based on observations showing that slow and fast solar wind have distinct properties like helium abundances, kinetic signatures, elemental composition, and charge-state ratios. Nominally, the fast wind…

Solar and Stellar Astrophysics · Physics 2025-03-28 B. L. Alterman , R. D'Amicis

Data obtained from Parker Solar Probe (PSP) since 2021 April have shown the first in situ observation of the solar corona, where the solar wind is formed and accelerated. Here we investigate the alpha-proton differential flow and its…

Solar and Stellar Astrophysics · Physics 2024-01-22 Hao Ran , Ying D. Liu , Chong Chen , Parisa Mostafavi

(abridged) We investigate how the properties of the corona and solar wind in the open coronal holes depend on the properties of the magnetic fields and their footpoint motions at the surface, by perfoming 1D MHD simulations from the…

Astrophysics · Physics 2015-06-24 Takeru K. Suzuki , Shu-ichiro Inutsuka

We investigate the nature of magnetic turbulent fluctuations, around ion characteristic scales, in a fast solar wind stream, by using {\it Cluster} data. Contrarily to slow solar wind, where both Alfv\'enic ($\delta b_{\perp} \gg \delta…

Plasma Physics · Physics 2017-11-08 D. Perrone , O. Alexandrova , O. W. Roberts , S. Lion , C. Lacombe , A. Walsh , M. Maksimovic , I. Zouganelis

One proposed mechanism for heating the solar wind, from close to the sun to beyond 10 AU, invokes low-frequency, oblique, Alfven-wave turbulence. Because small-scale oblique Alfven waves (kinetic Alfven waves) are compressive, the measured…

Solar and Stellar Astrophysics · Physics 2015-05-13 Benjamin D. G. Chandran , Eliot Quataert , Gregory G. Howes , Qian Xia , Peera Pongkitiwanichakul

The solar wind shows periods of highly Alfv\'enic activity, where velocity fluctuations and magnetic fluctuations are aligned or anti-aligned with each other. It is generally agreed that solar wind plasma velocity and magnetic field…

We discuss properties of large amplitude magnetic field fluctuations during fast Alfvenic solar wind streams, focussing on the statistics of the rotation angle between consecutive magnetic field vector measurements for different scales in…

Space Physics · Physics 2019-10-17 L. Matteini , D. Stansby , T. S. Horbury , C. H. K. Chen

During Parker Solar Probe's first orbit, the solar wind plasma has been observed in situ closer than ever before, the perihelion on November 6th 2018 revealing a flow that is constantly permeated by large amplitude Alfv\'enic fluctuations.…

‹ Prev 1 2 3 10 Next ›