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Related papers: Cross Helicity Reversals In Magnetic Switchbacks

200 papers

Using the results of laboratory experiments and direct numerical simulations, as well as observations of the full-disc solar magnetic field and sunspot number dynamics, it is demonstrated that cross-helicity can dominate the frequency power…

Fluid Dynamics · Physics 2025-10-16 A. Bershadskii

The solar wind is a dynamic plasma outflow that shapes heliospheric conditions and drives space weather. Identifying its large-scale phenomena is crucial, yet the increasing volume of high-cadence Parker Solar Probe (PSP) observations poses…

Solar and Stellar Astrophysics · Physics 2025-11-03 Valmir P Moraes Filho , Daniela Martin , Jasmine R. Kobayashi , Connor O'Brien , Jinsu Hong , Evangelia Samara , Joseph Gallego

Using a recently developed two-scale formalism to determine the magnetic helicity spectrum (Brandenburg et al. 2017), we analyze synoptic vector magnetograms built with data from the Vector Spectromagnetograph (VSM) instrument on the…

Solar and Stellar Astrophysics · Physics 2019-01-14 Nishant K. Singh , Maarit J. Käpylä , Axel Brandenburg , Petri J. Käpylä , Andreas Lagg , Ilpo Virtanen

It has long been known that the energy in velocity and magnetic field fluctuations in the solar wind is not in equipartition. In this paper, we present an analysis of 5 years of Wind data at 1 AU to investigate the reason for this. The…

Space Physics · Physics 2013-06-10 C. H. K. Chen , S. D. Bale , C. S. Salem , B. A. Maruca

We investigate the generation and evolution of switchbacks (SBs), the nature of the sub-Alfv\'enic wind observed by Parker Solar Probe (PSP), and the morphology of the Alfv\'enic transition, all of which are key issues in solar wind…

Solar and Stellar Astrophysics · Physics 2023-02-22 Ying D. Liu , Hao Ran , Huidong Hu , Stuart D. Bale

The Parker Solar Probe (PSP) primary mission extends seven years and consists of 24 orbits of the Sun with descending perihelia culminating in a closest approach of ($\sim 9.8~R_\odot$). In the course of these orbits PSP will pass through…

Solar and Stellar Astrophysics · Physics 2019-05-29 Rohit Chhiber , Arcadi V. Usmanov , William H. Matthaeus , Tulasi N. Parashar , Melvyn L. Goldstein

Traditionally, fast solar wind is considered to originate in solar source regions that are continuously open to the heliosphere and slow wind originates in regions that are intermittently open to it. In fast wind, the gradient of the solar…

Space Physics · Physics 2025-12-29 B. L. Alterman , R. D'Amicis

Since Parker Solar Probe's (Parker's) first perihelion pass at the Sun, large amplitude Alfv\'en waves grouped in patches have been observed near the Sun throughout the mission. Several formation processes for these magnetic switchback…

A fraction of solar active regions are observed to have current helicity of a sign that contradicts the polarity law for magnetic helicity; this law corresponds to the well-known Hale polarity law for sunspots. A significant excess of…

Astrophysics · Physics 2009-11-11 D. Sokoloff , S. D. Bao , N. Kleeorin , K. Kuzanyan , D. Moss , I. Rogachevskii , D. Tomin , H. Zhang

In a previous work we analysed the white-light coronal brightness as a function of elongation and time from Wide-Field Imager (WISPR) observations on board the Parker Solar Probe (PSP) mission when PSP reached a minimum heliocentric…

Solar and Stellar Astrophysics · Physics 2023-08-23 Spiros Patsourakos , Angelos Vourlidas , Alexander Nindos

The long-term evolution of the Sun's rotation period cannot be directly observed, and is instead inferred from trends in the measured rotation periods of other Sun-like stars. Assuming the Sun spins-down as it ages, following rotation rate…

The study of the sphericity of primary charged particles in minimum bias proton-proton collisions at 0.9, 2.76 and 7 TeV with the ALICE detector at the LHC is presented. The mean sphericity as a function of multiplicity is reported for…

High Energy Physics - Experiment · Physics 2019-08-13 Antonio Ortiz

In this paper we study the effects of hemispheric imbalance of magnetic helicity density on breaking the equatorial reflection symmetry of the dynamo generated large-scale magnetic field. Our study employs the axisymmetric dynamo model…

Solar and Stellar Astrophysics · Physics 2020-06-17 S. Yang , V. V. Pipin , D. D. Sokoloff , K. M. Kuzanyan , H. Zhang

Helical magnetohydrodynamic turbulence with Hall effects is ubiquitous in heliophysics and plasma physics, such as star formation and solar activities, and its intrinsic mechanisms are still not clearly explained. Direct numerical…

Plasma Physics · Physics 2024-05-07 Running Hu , Jin-Han Xie , Xinliang Li , Changping Yu , Yuan Hu , Jianchun Wang , Shiyi Chen

In this work, we quantify the effects of solar wind expansion on the dispersive properties of the three normal modes of ideal MHD using the Expanding Box Model, under a background magnetic field that follows the Parker spiral geometry. From…

Solar and Stellar Astrophysics · Physics 2026-01-12 Sebastián Saldivia , Felipe Asenjo , Pablo S. Moya

Turbulence, a ubiquitous phenomenon in interplanetary space, is crucial for the energy conversion of space plasma at multiple scales. This work focuses on the propagation, polarization and wave composition properties of the solar wind…

Space Physics · Physics 2020-09-09 Xingyu Zhu , Jiansen He , Daniel Verscharen , Die Duan , Stuart D. Bale

We use magnetic helicity to characterise solar wind fluctuations at proton-kinetic scales from Wind observations. For the first time, we separate the contributions to helicity from fluctuations propagating at angles quasi-parallel and…

The exploration of the inner heliosphere by Parker Solar Probe has revealed a highly structured solar wind with ubiquitous deflections from the Parker spiral, known as switchbacks. Interchange reconnection (IR) may play an important role in…

Observations at 1 au have confirmed that enhancements in measured energetic particle fluxes are statistically associated with "rough" magnetic fields, i.e., fields having atypically large spatial derivatives or increments, as measured by…

Parker Solar Probe (PSP) achieved its first orbit perihelion on November 6, 2018, reaching a heliocentric distance of about 0.165 au (35.55 R$_\odot$). Here, we study the evolution of fully developed turbulence associated with the slow…