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相关论文: Scaling in long term data sets of geomagnetic indi…

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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…

Motivated by recent observations of distinct parallel and perpendicular signatures in magnetic helicity measurements segregated by wave period and angle between the local magnetic field and the solar wind velocity, this paper undertakes a…

等离子体物理 · 物理学 2015-06-19 Kristopher G. Klein , Gregory G. Howes , Jason M. TenBarge , John J. Podesta

In this work, we perform a statistical study of magnetic field fluctuations in the solar wind at 1 au using permutation entropy and complexity analysis, and the investigation of the temporal variations of the Hurst exponents. Slow and fast…

太阳与恒星天体物理 · 物理学 2024-03-26 Emilia Kilpua , Simon Good , Matti Ala-Lahti , Adnane Osmane , Venla Koikkalainen

The Interplanetary Magnetic Field shows complex spatial and temporal variations. Single spacecraft measurements reveal only a one dimensional section of this rich four dimensional phenomenon. Multi-point measurements of the four Cluster…

空间物理 · 物理学 2015-05-19 Z. Németh , G. Facskó , E. A. Lucek

Interplanetary magnetic field magnitude fluctuations are notoriously more intermittent than velocity fluctuations in both fast and slow wind. This behaviour has been interpreted in terms of the anomalous scaling observed in passive scalars…

天体物理学 · 物理学 2009-11-13 Roberto Bruno , Vincenzo Carbone , Sandra Chapman , Bogdan Hnat , Alain Noullez , Luca Sorriso-Valvo

The solar wind provides a natural laboratory for observations of MHD turbulence over extended temporal scales. Here, we apply a model independent method of differencing and rescaling to identify self-similarity in the Probability Density…

空间物理 · 物理学 2009-11-07 Bogdan Hnat , Sandra C. Chapman , George Rowlands

We analyzed intermittency in the solar wind, as observed on the ecliptic plane, looking at magnetic field and velocity fluctuations between 0.3 and 1 AU, for both fast and slow wind and for compressive and directional fluctuations. Our…

天体物理学 · 物理学 2015-06-24 R. Bruno , V. Carbone , L. Sorriso-Valvo , B. Bavassano

To investigate the power and spectral index anisotropy in the inertial range of solar wind turbulence, we use 70 intervals of electric field data accumulated by Cluster spacecraft in the free solar wind. We compute the electric field…

空间物理 · 物理学 2020-09-24 Deepali , Supratik Banerjee

We investigated the behavior of the spectral slope of interplanetary magnetic field fluctuations at proton scales for selected high resolution time intervals from WIND and MESSENGER spacecraft at $1$ AU and $0.56$ AU, respectively. The…

太阳与恒星天体物理 · 物理学 2015-06-22 R. Bruno , L. Trenchi , D. Telloni

We present a measurement of the scale-dependent, three-dimensional structure of the magnetic field fluctuations in inertial range solar wind turbulence with respect to a local, physically motivated coordinate system. The Alfvenic…

空间物理 · 物理学 2012-10-09 C. H. K. Chen , A. Mallet , A. A. Schekochihin , T. S. Horbury , R. T. Wicks , S. D. Bale

We analyze offshore wind speeds with a time resolution of one second over a long period of 20 months for different heights above the sea level. Energy spectra extending over more than seven decades give a comprehensive picture of wind…

流体动力学 · 物理学 2023-10-20 So-Kumneth Sim , Joachim Peinke , Philipp Maass

Context. Solar activity cycles vary in amplitude and duration. The variations can be at least partly explained by fluctuations in dynamo parameters. Aims. We want to restrict uncertainty in fluctuating dynamo parameters and find out which…

太阳与恒星天体物理 · 物理学 2018-07-18 L. L. Kitchatinov , A. V. Mordvinov , A. A. Nepomnyashchikh

Context. Large-amplitude inversions of the solar wind's interplanetary magnetic field have long been documented; however, observations from the Parker Solar Probe (PSP) mission have renewed interest in this phenomenon as such features,…

The anisotropic nature of solar wind magnetic turbulence fluctuations is investigated scale-by-scale using high cadence in-situ magnetic field measurements from the Cluster and ACE spacecraft missions. The data span five decades in scales…

We show that the scaling of structure functions of magnetic and velocity fields in a mostly highly Alfv\'{e}nic fast solar wind stream depends strongly on the joint distribution of the dimensionless measures of cross helicity and residual…

The analysis of long-term variations of several solar activity indices (AI) since in last 40 years has been performed. We studied the AI which characterize the fluxes from different areas in solar atmosphere. Our consideration of mutual…

太阳与恒星天体物理 · 物理学 2019-01-01 E. A. Bruevich , V. V. Bruevich

We investigate the spatial correlation properties of the solar wind using simultaneous observations by the ACE and WIND spacecraft. We use mutual information as a nonlinear measure of correlation and compare this to linear correlation. We…

空间物理 · 物理学 2010-02-11 R. T. Wicks , S. C. Chapman , R. O. Dendy

The mixture/interaction of anti-sunward-propagating Alfv\'enic fluctuations (AFs) and sunward-propagating Alfv\'enic fluctuations (SAFs) is believed to result in the decrease of the Alfv\'enicity of solar wind fluctuations with increasing…

空间物理 · 物理学 2016-06-13 H. Li , C. Wang , J. W. Belcher , J. S. He , J. D. Richardson

We establish that global solar p-mode frequencies can be measured with sufficient precision on time scales as short as nine days to detect activity-related shifts. Using ten years of GONG data, we report that mode-mass and error-weighted…

天体物理学 · 物理学 2009-02-10 S. C. Tripathy , F. Hill , K. Jain , J. W. Leibacher

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…