English
Related papers

Related papers: Relating streamer flows to density and magnetic st…

200 papers

We investigate the origin of mesoscale structures in the solar wind called microstreams defined as enhancements in solar wind speed and temperature that last several hours. They were first clearly detected in Helios and Ulysses solar wind…

Solar and Stellar Astrophysics · Physics 2023-10-24 Bahaeddine Gannouni , Victor Réville , Alexis Rouillard

We find that the element abundances in solar energetic particles (SEPs) and in the slow solar wind (SSW), relative to those in the photosphere, show different patterns as a function of the first ionization potential (FIP) of the elements.…

Solar and Stellar Astrophysics · Physics 2018-03-13 Donald V. Reames

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…

Solar wind stream interaction regions (SIRs) are often characterized by energetic ion enhancements. The mechanisms accelerating these particles, as well as the locations where the acceleration occurs, remain debated. Here, we report the…

Space Physics · Physics 2021-02-23 Nicolas Wijsen , Evangelia Samara , Àngels Aran , David Lario , Jens Pomoell , Stefaan Poedts

Magnetic switchbacks, or sudden reversals in the magnetic field's radial direction, are one of the more striking observations of Parker Solar Probe (PSP) thus far in its mission. While their precise production mechanisms are still unknown,…

Analysis of the Interball-1 spacecraft data (1995-2000) has shown that the solar wind ion flux sometimes increases or decreases abruptly by more than 20% over a time period of several seconds or minutes. Typically, the amplitude of such…

Space Physics · Physics 2011-02-08 Olga Khabarova , Georgy Zastenker

The role of small-scale coronal eruptive phenomena in the generation and heating of the solar wind remains an open question. Here, we investigate the role played by coronal jets in forming the solar wind by testing whether temporal…

Solar and Stellar Astrophysics · Physics 2021-04-28 Diego de Pablos , David M. Long , Christopher J. Owen , Gherardo Valori , Georgios Nicolaou , Louise K. Harra

The detected population of "spiders" has significantly grown in the past decade thanks to multiwavelength follow-up investigations of unidentified Fermi sources. These systems consist of low-mass stellar companions orbiting rotation-powered…

High Energy Astrophysical Phenomena · Physics 2024-07-24 C. Guerra , Z. Meliani , G. Voisin

The first two orbits of the Parker Solar Probe (PSP) spacecraft have enabled the first in situ measurements of the solar wind down to a heliocentric distance of 0.17 au (or 36 Rs). Here, we present an analysis of this data to study solar…

Helmet streamers are a prominent manifestation of magnetic structures with current sheets in the solar corona. These large-scale structures are regions with high plasma density, overlying active regions and filament channels. We investigate…

Solar and Stellar Astrophysics · Physics 2019-10-04 Bieke Decraemer , Andrei N. Zhukov , Tom Van Doorsselaere

Recent observations have shown that coronal shocks driven by coronal mass ejections can develop and accelerate particles within several solar radii in large solar energetic particle (SEP) events. Motivated by this, we present an SEP…

Solar and Stellar Astrophysics · Physics 2017-12-20 Xiangliang Kong , Fan Guo , Joe Giacalone , Hui Li , Yao Chen

Small-scale transient jetlet activity and associated upflows from coronal hole plumes are potential sources of the solar wind. To elucidate the magnetic origins and driving mechanisms of such upflows, we perform three-dimensional radiative…

Solar and Stellar Astrophysics · Physics 2025-11-18 Kamlesh Bora , Lakshmi Pradeep Chitta , Yajie Chen , Damien Przybylski , David Pontin , Nikil Panyam

Solar energetic particle (SEP) events have been observed by the Parker Solar Probe (PSP) spacecraft since its launch in 2018. These events include sources from solar flares and coronal mass ejections (CMEs). Onboard PSP is the IS\(\odot\)IS…

Magnetic field fluctuations in the solar wind are commonly observed to follow a power law spectrum. Near proton-kinetic scales, a spectral break occurs which is commonly interpreted as a transition to kinetic turbulence. However, this…

Filaments/prominences are cold plasma (~ 10000 K) embedded in the solar corona, two orders of magnitude hotter. Filament plasma is structured by the magnetic field in thin elongated threads. Counter-streaming flows have been observed. The…

Solar and Stellar Astrophysics · Physics 2025-06-24 Garima Karki , Brigitte Schmieder , Pascal Demoulin , Pooja Devi , Ramesh Chandra , Reetika Joshi

The transition from subAlfv\'enic to superAlfv\'enic flow in the solar atmosphere is examined by means of Parker Solar Probe (PSP) measurements during solar encounters 8 to 14. Around 220 subAlfv\'enic periods with a duration $\ge$ 10…

The fast solar wind that fills the heliosphere originates from deep within regions of open magnetic field on the Sun called coronal holes. The energy source responsible for accelerating the plasma to high speeds is widely debated, however…

Magnetic switchbacks are large amplitude deflections of the magnetic field within the solar wind. They are Alfv\'enic in character and so are associated with a spike in velocity and a generally small variation in local plasma density. Early…

This letter describes a new phenomenon on the Parker Solar Probe of recurring plasma density enhancements that have $\Delta$n/n ~10% and that occur at a repetition rate of ~5 Hz. They were observed sporadically for about five hours between…

Solar and Stellar Astrophysics · Physics 2023-08-01 F. S. Mozer , O. Agapitov , S. D. Bale , R. Livi , O. Romeo , K. Sauer , I. Y. Vasko , J. Verniero

The last solar minimum is characterized by several peculiar aspects and by the presence of a complex magnetic topology with two different kinds of coronal streamers: pseudo-streamers and bipolar streamers. Pseudo-streamers or unipolar…

Solar and Stellar Astrophysics · Physics 2015-07-15 Lucia Abbo , Roberto Lionello , Pete Riley , Yi-Ming Wang