Download or read book Magnetic Reconnection and Turbulence in the Inner Heliosphere written by Chen Shi and published by . This book was released on 2020 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, we discuss two fundamental processes in the inner heliosphere: magnetic reconnection and turbulence. Understanding the two processes is crucial for a more complete description of the solar atmosphere and solar wind. Our studies are confined within magnetohydrodynamic (MHD) and Hall-MHD regimes. We employ methods of linear stability analysis, numerical simulation, as well as satellite data analysis. The main results of our studies are summarized as follows. (1) Through linear stability calculation and linear MHD simulations, we confirm that the inhomogeneous flow inside a reconnecting current sheet stabilizes the tearing instability. The threshold Lundquist number $S_c$ for stabilization is on the order of $10^4$. (2) Through nonlinear Hall-MHD simulations, we show that during the ``recursive'' reconnection process driven by tearing instability, the generation of secondary plasmoids is suppressed as the system scale approaches the ion inertial length. (3) We calculate the linear dispersion relation of the tearing instability under a generalized three-dimensional configuration with Hall effect and guide field. We show that the largest linear growth rate is in general found in parallel modes rather than oblique modes, regardless of the guide field strength. (4) We carry out high-resolution two-dimensional MHD simulations, based on expanding-box-model (EBM), of Alfv\'en waves propagating inside large-scale solar wind streams. We show that the stream structures significantly impact the evolution of Alfv\'enic turbulence properties, such as the cross helicity and residual energy. (5) Through the EBM simulations in combination with a superposed-epoch analysis using OMNI data set, we show that, around heliospheric current sheets (HCSs), the Alfv\'enicity of the solar wind turbulence is destroyed. (6) We analyze Parker Solar Probe (PSP) data of the first four orbits and carry out a statistical study of the turbulence properties in the young solar wind. A radial evolution of various turbulence properties is observed in the data.
Download or read book Physics of the Inner Heliosphere II written by Rainer Schwenn and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physics of the Inner Heliosphere gives for the first time a comprehensive and complete summary of our knowledge of the inner solar system. Using data collected over more than 11 years by the HELIOS twin solar probes, one of the most successful ventures in unmanned space exploration, the authors have compiled six extensive reviews of the physical processes of the inner heliosphere and their relation to the solar atmosphere. Researchers and advanced students in space and plasma physics, astronomy, and solar physics will be surprised to see just how closely the heliosphere is tied to, and how sensitively it depends on, the sun. Volume 2 deals with particles, waves, and turbulence, with chapters on: - magnetic clouds - interplanetary clouds - the solar wind plasma and MHD turbulence - waves and instabilities - energetic particles in the inner solar system
Download or read book Physics of the Inner Heliosphere II written by Rainer Schwenn and published by Springer. This book was released on 1991-07-30 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physics of the Inner Heliosphere gives for the first time a comprehensive and complete summary of our knowledge of the inner solar system. Using data collected over more than 11 years by the HELIOS twin solar probes, one of the most successful ventures in unmanned space exploration, the authors have compiled six extensive reviews of the physical processes of the inner heliosphere and their relation to the solar atmosphere. Researchers and advanced students in space and plasma physics, astronomy, and solar physics will be surprised to see just how closely the heliosphere is tied to, and how sensitively it depends on, the sun. Volume 2 deals with particles, waves, and turbulence, with chapters on: - magnetic clouds - interplanetary clouds - the solar wind plasma and MHD turbulence - waves and instabilities - energetic particles in the inner solar system
Download or read book Magnetic Reconnection and Turbulence written by M. A. Dubois and published by S.N. Publishing Company. This book was released on 1986 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Magnetic Reconnection written by Walter Gonzalez and published by Springer. This book was released on 2016-02-22 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an overview of recent research highlights in the main areas of application of magnetic reconnection (MR), including planetary, solar and magnetospheric physics and astrophysics. It describes how research on magnetic reconnection, especially concerning the Earth's magnetosphere, has grown extensively due to dedicated observations from major satellite missions such as Cluster, Double Star and Themis. The accumulated observations from these missions are being supplemented by many theoretical and modelling efforts, for which large scale computer facilities are successfully being used, and the theoretical advances are also covered in detail. Opening with an introductory discussion of some fundamental issues related to magnetic reconnection, subsequent chapters address topics including collisionless magnetic reconnection, MHD structures in 3D reconnection, energy conversion processes, fast reconnection mediated by plasmoids, rapid reconnection and magnetic field topology. Further chapters consider specific areas of application such as magnetospheric dayside and tail reconnection, comparative reconnection in planetary systems and reconnection in astrophysical systems. The book offers insight into discussions about fundamental concepts and key aspects of MR, access to the full set of applications of MR as presently known in space physics and in astrophysics, and an introduction to a new related area of study dealing with the annihilation of quantum magnetic fluxes and its implications in the study on neutron star activity. The book is aimed primarily at students entering the field, but will also serve as a useful reference text for established scientists and senior researchers.
Download or read book Turbulence in Magnetohydrodynamics written by Andrey Beresnyak and published by Walter de Gruyter GmbH & Co KG. This book was released on 2019-07-08 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetohydrodynamics describes dynamics in electrically conductive fluids. These occur in our environment as well as in our atmosphere and magnetosphere, and play a role in the sun's interaction with our planet. In most cases these phenomena involve turbulences, and thus are very challenging to understand and calculate. A sound knowledge is needed to tackle these problems. This work gives the basic information on turbulence in nature, comtaining the needed equations, notions and numerical simulations. The current state of our knowledge and future implications of MHD turbulence are outlined systematically. It is indispensable for all scientists engaged in research of our atmosphere and in space science.
Download or read book The Role of Turbulence in the Solar Wind Magnetosphere Ionosphere Dynamics written by Marina Stepanova and published by Frontiers Media SA. This book was released on 2022-03-24 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulence in the Solar Wind written by Roberto Bruno and published by Springer. This book was released on 2016-10-07 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an overview of solar wind turbulence from both the theoretical and observational perspective. It argues that the interplanetary medium offers the best opportunity to directly study turbulent fluctuations in collisionless plasmas. In fact, during expansion, the solar wind evolves towards a state characterized by large-amplitude fluctuations in all observed parameters, which resembles, at least at large scales, the well-known hydrodynamic turbulence. This text starts with historical references to past observations and experiments on turbulent flows. It then introduces the Navier-Stokes equations for a magnetized plasma whose low-frequency turbulence evolution is described within the framework of the MHD approximation. It also considers the scaling of plasma and magnetic field fluctuations and the study of nonlinear energy cascades within the same framework. It reports observations of turbulence in the ecliptic and at high latitude, treating Alfvénic and compressive fluctuations separately in order to explain the transport of mass, momentum and energy during the expansion. Further, existing models are compared with direct observations in the heliosphere. The problem of self-similar and anomalous fluctuations in the solar wind is then addressed using tools provided by dynamical system theory and discussed on the basis of available models and observations. The book highlights observations of Yaglom’s law in solar wind turbulence, which is one of the most important findings in fully developed turbulence and directly related to the long-lasting and still unsolved problem of solar wind plasma heating. Lastly, it includes a short chapter dedicated to the kinetic range of fluctuations, which has recently been receiving more attention from the space plasma community, since this is inherently related to turbulent energy dissipation and consequent plasma heating. It particularly focuses on the nature and role of the fluctuations populating this frequency range, and discusses several model predictions and recent observational findings in this context.
Download or read book Plasma Physics of the Local Cosmos written by National Research Council and published by National Academies Press. This book was released on 2004-06-06 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solar and space physics is the study of solar system phenomena that occur in the plasma state. Examples include sunspots, the solar wind, planetary magnetospheres, radiation belts, and the aurora. While each is a distinct phenomenon, there are commonalities among them. To help define and systematize these universal aspects of the field of space physics, the National Research Council was asked by NASA's Office of Space Science to provide a scientific assessment and strategy for the study of magnetized plasmas in the solar system. This report presents that assessment. It covers a number of important research goals for solar and space physics. The report is complementary to the NRC report, The Sun to the Earthâ€"and Beyond: A Decadal Research Strategy for Solar and Space Physics, which presents priorities and strategies for future program activities.
Download or read book Cosmic Winds and the Heliosphere written by J. R. Jokipii and published by University of Arizona Press. This book was released on 2018-01-30 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt: Until the advent of space physics, astrophysical plasmas could be studied only using ground-based observations. Although observational methods have advanced over recent decades, the merging of heliospheric physics with astrophysics is far from complete due to the vastly different techniques employed by astronomers and space physicists. That astrophysical plasmas can be studies directly is a major advance in astrophysical research. The solar wind from the Sun is only one of many examples of solar winds, but it provides scientists with a basis for understanding how these formerly disparate disciplines are related. Cosmic Winds and the Heliosphere is a comprehensive sourcebook on conceptually correlated topics in astrophysical winds and heliospheric physics. The contributors review the various kinds of winds, such as solar wind, winds of cataclysmic variables, and winds from pulsating stars. They then examine the physics of wind origin and physical phenomena in winds. including heliospheric shocks, magnetohydrodynamic turbulence, and kinetic phenomena. A final section considers interactions with surrounding media, with contributions ranging from studies of the interstellar cloud surrounding the solar system to considerations of solar wind interaction with comets. Prepared to the scrupulous standards of the University of Arizona Space Science Series, Cosmic Winds and the Heliosphere is an essential volume for astronomers and space physicists.
Download or read book Interplay Between Magnetic Reconnection and Turbulence written by Subash Adhikari and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reconnection and turbulence frequently occur in plasmas, including laboratory, astrophysical and space plasmas. Over the past few decades, the interrelationship between turbulence and magnetic reconnection has been the focus of increasing scrutiny with significant research on the statistics of reconnection as an element of turbulence, the generation of turbulence due to instabilities associated with reconnection, and the effect of reconnection on the turbulent cascade. However, none of these studies directly address the universal properties that may relate reconnection and turbulence, i.e., ``What are the turbulent-like features of laminar magnetic reconnection?'' and ``Is magnetic reconnection fundamentally an energy cascade?'' To answer these questions, we analyze 2.5D fully kinetic particle-in-cell (PIC) simulations of reconnection and turbulence. First, we start with a laminar anti-parallel reconnection with no initial turbulent fluctuations. Even with no secondary instabilities, the reconnection process in its quasi-steady phase is found to generate a magnetic energy spectrum with a spectral index of -5/3 at scales larger than the ion-inertial length, in accordance with Kolmogorov turbulence. Further, the scale-to-scale energy transfer process is studied using the von-Karman Howarth equation generalized to Hall Magnetohydrodynamic (MHD) systems. Most notably, the energy transfer in laminar magnetic reconnection is also found to be similar to that of a turbulent system suggesting that reconnection involves an energy cascade. Consistent with this similarity, the reconnection rate is positively correlated to both the magnetic energy spectrum in the ion-scales and the cascade of energy. Next, we investigate how robust the antiparallel reconnection results are by generalizing them to reconnection with smaller magnetic shear (guide field reconnection). The guide field does not fundamentally change the energy transfer properties of reconnection. Finally, we study how the electric field spectrum and its constituent physical terms in Ohm's law are modified by changing the guide field in reconnection. Unlike the magnetic spectrum, the electric field spectrum drastically changes with guide field. At MHD length scales, there is a flat spectrum for the antiparallel case and a gradual steepening to a -5/3 slope with increasing guide field. In summary, the striking similarities found between the reconnection and turbulence simulations imply that both processes are fundamentally energy cascades, and raises the intriguing possibility of a fundamental universality linking the two.
Download or read book Turbulence in Magnetohydrodynamics written by Andrey Beresnyak and published by Walter de Gruyter GmbH & Co KG. This book was released on 2019-07-08 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetohydrodynamics describes dynamics in electrically conductive fluids. These occur in our environment as well as in our atmosphere and magnetosphere, and play a role in the sun's interaction with our planet. In most cases these phenomena involve turbulences, and thus are very challenging to understand and calculate. A sound knowledge is needed to tackle these problems. This work gives the basic information on turbulence in nature, comtaining the needed equations, notions and numerical simulations. The current state of our knowledge and future implications of MHD turbulence are outlined systematically. It is indispensable for all scientists engaged in research of our atmosphere and in space science.
Download or read book Multiscale Coupling of Sun Earth Processes written by A.T.Y. Lui and published by Elsevier. This book was released on 2005-07-06 with total page 527 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many approaches exist for scientific investigations and space research is no exception. The early approach during which each space plasma region within the Sun-Earth system was investigated separately with physics-based tools has now progressed to encompass investigations on coupling between these regions. Ample evidence now exists indicating the dynamic processes in these regions exhibit disturbances over a wide range of scales both in time and space. This new reckoning naturally leads to an emerging perspective of probing these natural phenomena with concepts and tools developed in modern statistical mechanics for physical processes governing the evolution of out-of-equilibrium and complex systems. These new developments have prompted a topical conference on Sun-Earth connection, held on February 9-13, 2004 at Kailua-Kona, Hawaii, USA, with the goal of promoting interactions among scientists practicing the traditional physics-based approach and those utilizing modern statistical techniques. This monograph is a product of this conference, a compilation of thirty-nine articles assembled into seven chapters: (1) multiscale features in complexity dynamics, (2) space storms, (3) magnetospheric substorms, (4) turbulence and magnetic reconnection, (5) modeling and coupling of space phenomena, (6) techniques for multiscale space plasma problems, and (7) present and future multiscale space missions. These articles show a diversity of space phenomena exhibiting scale free characteristics, intermittency, and non-Gaussian distributions of probability density function of fluctuations in the physical parameters of the Sun-Earth system. The scope covers the latest observations, theories, simulations, and techniques on the multiscale nature of Sun-Earth phenomena and underscores the usefulness in cross-disciplinary exchange needed to unravel the underlying physical processes, which may eventually lead to a possible unified description and prediction for space disturbances. * Extensive collection of state-of-the-art papers on multiscale coupling of Sun-Earth Processes * Present and future multiscale space missions * New techniques and models for performing multiscale analysis
Download or read book Interplanetary Magnetohydrodynamics written by L. F. Burlaga and published by Oxford University Press, USA. This book was released on 1995-09-07 with total page 267 pages. Available in PDF, EPUB and Kindle. Book excerpt: Data from spacecraft such as Pioneer, Vela and Voyager have revealed the interstellar medium to be a remarkable physical system, which has served as a laboratory for the study of turbulent, supersonic, ideal magnetohydrodynamic (MHD) flows. The results of these studies provided confirmation of many theoretical models of the interstellar medium.
Download or read book Magnetic Reconnection and Turbulence written by M. A. Dubois and published by . This book was released on 1986 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Particle Acceleration and Transport in the Heliosphere and Beyond written by Gang Li and published by American Institute of Physics. This book was released on 2008-09-12 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: All papers have been peer-reviewed. Our star is a very effective particle accelerator. Energies up to GeVs have been observed in Solar energetic particle events. These events are often associated with solar flares and/or Coronal Mass Ejections. Understanding how particles are accelerated in these phenomena has been an outstanding problem in space plasma physics for a long time. Part of the reason is its practical (e.g. Space weather) and fundamental (cosmic ray origin) importance. In this conference we review recent progresses on this problem, with a balance between observations, theories and numerical simulations. Specific topics include 1) particle acceleration at flare site, 2) turbulence properties of the solar wind, 3) particle acceleration and transport in the inner heliosphere, 4) particle acceleration at the termination shock and heliosheath, and 5) particle acceleration at supernova remnant shocks.
Download or read book Magnetic Cloud Boundary Layers and Magnetic Reconnection written by Yi Wang and published by Springer. This book was released on 2015-08-21 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis focuses on magnetic reconnection processes in the boundary layer of the interplanetary magnetic cloud. Magnetic reconnection is an important and frontier topic in the realm of physics. Various physical phenomena can be observed during the reconnection process but lots of them are not fully understood. This thesis provides the first observational evidence of energetic electrons associated with magnetic reconnection in the solar wind and discusses the particle acceleration problems. In addition, after analyzing the particle flux variations in Magnetic Cloud Boundary Layer, the thesis proposes a possible new criterion for the identification of magnetic reconnection in the solar wind. These tantalizing results could be particular clues to understand the dynamical problems in magnetic reconnection processes.
