Download or read book Magnetic Reconnection in the Age of the Magnetospheric Multiscale Mission written by Blake Alastair Wetherton and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic reconnection is a process that converts magnetic energy into kinetic energy in a plasma system through a change in topology of the magnetic field lines, and it allows explosive events such as coronal mass ejections and sawtooth crashes in magnetically-confined nuclear fusion experiments to occur. Reconnection mediates the transfer of solar wind plasma into Earth's magnetosphere. To learn more about the process of magnetic reconnection, NASA launched its Magnetospheric Multiscale (MMS) mission in 2015. In this thesis, we consider aspects of magnetic reconnection in relation to MMS observations and goals. We begin by further examining anisotropic equations of state (EoS) previously developed to describe the pressure parallel to and perpendicular to the local magnetic field. We find that the EoS holds near the x-line for an MMS event in the guide-field regime, and hybrid simulations (kinetic ions, fluid electrons with the EoS as a closure) are able to properly reproduce the MMS observations. We then apply the EoS to derive scalings of the electron bulk heating in the exhaust with upstream parameters. Afterwords, we examine another MMS event in the guide-field regime, this time much farther from the x-line, and show that the EoS also hold here. This event took place in a region of active compression, and we extend the model of the EoS to account for the energy gains from compression, showing that local electron trapping plays a role in additional perpendicular heating of the electrons. Finally, we present a drift-kinetic method that links agyrotropy, the lack of symmetry in the velocity space plane perpendicular to the magnetic field, to gradients in plasma properties. The method can predict gradients in fluid properties of the plasma based on a distribution function measured at a single spatial point, and could add significant utility to MMS observations.
Download or read book Magnetospheric Multiscale written by James L. Burch and published by Springer. This book was released on 2016-12-16 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: NASA’s Magnetospheric Multiscale (MMS) mission is a four-spacecraft Solar Terrestrial Probe mission to study magnetic reconnection, a fundamental plasma physical process in which energy stored in a magnetic field is converted into the kinetic energy of charged particles and heat. The driver of eruptive solar events such as flares and coronal mass ejections, magnetic reconnection is also the process by which energy is transferred from the solar wind to Earth’s magnetosphere. Flying in a tetrahedral formation, the four identically instrumented MMS spacecraft measure the plasma, electric and magnetic fields, and energetic particles in the regions of geospace where magnetic reconnection is expected to occur. With interspacecraft distances varying from 400 km to 10 km and instruments capable of making extremely fast measurements (30 ms for electrons), MMS has the spatial and temporal resolution needed to resolve for the first time the microphysics of the electron diffusion region. Here, the magnetic field and the plasma become decoupled, allowing reconnection to occur. During the first of its two mission phases, MMS targets the dayside magnetopause, where the interplanetary and terrestrial magnetic fields reconnect. In the second phase, MMS increases its apogee from 12 RE to 25 RE and probes the nightside magnetosphere, where energy stored in the stretched field lines of the magnetotail is explosively released in magnetospheric substorms. Launched in March 2015 into a low-inclination elliptical orbit, MMS is now in Phase 1 of science operations. This volume, which describes the MMS mission design, observatories, instrumentation, and operations, is aimed at researchers and graduate students in magnetospheric physics and plasma physics. Researchers using the publicly available MMS data will find it particularly useful. Previously published in Space Science Reviews, Volume 199, Nos. 1-4, 2016.
Download or read book Magnetic Reconnection written by William Lewis and published by Springer. This book was released on 2012-03-18 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume covers different aspects of recent theoretical and observational work on magnetic reconnection, a fundamental plasma-physical process by which energy stored in magnetic field is converted, often explosively, into heat and kinetic energy. This collection of papers from the fields of solar and space physics, astrophysics, and laboratory plasma physics is especially timely in view of NASA's upcoming Magnetospheric Multiscale mission, which will use Earth's magetosphere as a laboratory to test, through in-situ measurement of the plasma, energetic particles, and electric and magnetic fields, the various and sometimes competing models and theories of magnetic reconnection. This volume is aimed at researchers in solar physics, magnetospheric physics and plasma physics. Previously published in Space Science Reviews journal, Vol. 160/1-4, 2011.
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 Magnetic Reconnection written by Masaaki Yamada and published by Princeton University Press. This book was released on 2022-04-19 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: The essential introduction to magnetic reconnection—written by a leading pioneer of the field Plasmas comprise more than 99 percent of the visible universe; and, wherever plasmas are, magnetic reconnection occurs. In this common yet incompletely understood physical process, oppositely directed magnetic fields in a plasma meet, break, and then reconnect, converting the huge amounts of energy stored in magnetic fields into kinetic and thermal energy. In Magnetic Reconnection, Masaaki Yamada offers an illuminating synthesis of modern research and advances on this important topic. Magnetic reconnection produces such phenomena as solar flares and the northern lights, and occurs in nuclear fusion devices. A better understanding of this crucial cosmic activity is essential to comprehending the universe and varied technological applications, such as satellite communications. Most of our knowledge of magnetic reconnection comes from theoretical and computational models and laboratory experiments, but space missions launched in recent years have added up-close observation and measurements to researchers’ tools. Describing the fundamental physics of magnetic reconnection, Yamada links the theory with the latest results from laboratory experiments and space-based observations, including the Magnetic Reconnection Experiment (MRX) and the Magnetospheric Multiscale (MMS) Mission. He concludes by considering outstanding problems and laying out a road map for future research. Aimed at advanced graduate students and researchers in plasma astrophysics, solar physics, and space physics, Magnetic Reconnection provides cutting-edge information on a vital area of scientific investigation.
Download or read book Magnetic Reconnection written by William Lewis and published by Springer. This book was released on 2014-02-23 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume covers different aspects of recent theoretical and observational work on magnetic reconnection, a fundamental plasma-physical process by which energy stored in magnetic field is converted, often explosively, into heat and kinetic energy. This collection of papers from the fields of solar and space physics, astrophysics, and laboratory plasma physics is especially timely in view of NASA's upcoming Magnetospheric Multiscale mission, which will use Earth's magetosphere as a laboratory to test, through in-situ measurement of the plasma, energetic particles, and electric and magnetic fields, the various and sometimes competing models and theories of magnetic reconnection. This volume is aimed at researchers in solar physics, magnetospheric physics and plasma physics. Previously published in Space Science Reviews journal, Vol. 160/1-4, 2011.
Download or read book Magnetic Reconnection written by William Lewis and published by Springer. This book was released on 2011-12-31 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume covers different aspects of recent theoretical and observational work on magnetic reconnection, a fundamental plasma-physical process by which energy stored in magnetic field is converted, often explosively, into heat and kinetic energy. This collection of papers from the fields of solar and space physics, astrophysics, and laboratory plasma physics is especially timely in view of NASA's upcoming Magnetospheric Multiscale mission, which will use Earth's magetosphere as a laboratory to test, through in-situ measurement of the plasma, energetic particles, and electric and magnetic fields, the various and sometimes competing models and theories of magnetic reconnection. This volume is aimed at researchers in solar physics, magnetospheric physics and plasma physics. Previously published in Space Science Reviews journal, Vol. 160/1-4, 2011.
Download or read book Reconstruction of Magnetic Reconnection Events written by Thomas Penz and published by Sudwestdeutscher Verlag Fur Hochschulschriften AG. This book was released on 2009 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic reconnection is a basic process taking place in plasmas on Earth and in space. After a general introduction, this work focusses on magnetic reconnection in the Earth' magnetosphere. Because of the interaction between the solar wind and the terrestrial magnetic field, magnetic field line merging is initiated under certain conditions, leading to various phenomena like the polar aurora or the injection of high-energetic particles influencing near-Earth satellites. The author presents a method to achieve detailed information about the reconnection process from remote satellite measurements. Therefore, an ill- posed inverse problem is solved using regularization theory. Using multi-spacecraft measurements, e.g. from the Cluster satellites, it is possible to gain information about the spatial location of the reconnection event, so this method presents a complementary approach to ground-based and in-situ satellite measurements. The work combines a thorough analysis of theoretical space plasma problems with experimental data from satellite missions and numerical simulations to provide new insights in this exciting field of space physics.
Download or read book Magnetic Reconnection on the Earth s Magnetopause written by Yi Qi and published by . This book was released on 2021 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic reconnection is a fundamental physical process that happens between anti-parallel magnetic field components. This process is ubiquitous and can be found in both laboratory and space plasma. At the same time, it modifies the field topology and converts energy explosively from field to plasma. With its universality and capability, magnetic reconnection has been an important subject for decades, and with improving observation/modeling techniques, we are able to keep advancing our knowledge on this topic. In this dissertation we utilize in-situ measurements from the Magnetospheric Multiscale (MMS) and numeric modeling. We first investigate the heart of magnetic reconnection, the X-line. Then we focus on the Flux Transfer Events (FTEs) which are products of magnetic reconnection on the Earth's magnetopause and the interactions between flux ropes that carry the reconnected magnetic flux. We apply magnetic curvature analysis to the electron diffusion region (EDR) crossings and x-line crossings. We find highly increased magnetic curvature. The radius of curvature can decrease to the order of electron gyro-radius, which is consistent with the small scale nature of the center of magnetic reconnection. Another essential property of magnetic reconnection is the magnetic flux transport during the annihilation and reformation of magnetic field lines. We develop a new method to quantitatively describe the magnetic flux transport (MFT) characteristics and test it in both simulations and observations. We find bidirectional Alfvenic inflow and outflow of magnetic flux in a specially limited region around the X-line. This transport pattern defines reconnection and produces a new quadrupolar pattern in the divergence of the magnetic flux transport velocity. As the reconnected magnetic flux is carried away from the initial reconnection site in the FTE, we discover magnetic entanglement and new pairs of flux ropes are born through the disentanglement enabled by the reconnection between two entangled flux tubes. We further identify three temporal evolutionary stages of magnetic entanglement. Three-dimensional Hall Magnetohydrodynamic (MHD) simulation verifies the feasibility of this process and shows it is mainly driven by the momentum of the ambient converging plasma.
Download or read book Magnetic Reconnection written by Eric Ronald Priest and published by . This book was released on 2000 with total page 600 pages. Available in PDF, EPUB and Kindle. Book excerpt: A lucid introduction to the theory of magnetic reconnection and a wide-ranging review of its applications.
Download or read book Dayside Magnetic Reconnection in Global Simulations of Earth s Magnetosphere written by Jeremy E. Ouellette and published by . This book was released on 2009 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Reconnection in the Solar Corona and Magnetospheric Substorms written by COSPAR. Scientific Assembly and published by Pergamon. This book was released on 1997 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paperback. Magnetic reconnection is a fundamental process in a space, solar or astrophysical plasma. It changes the connectivity of plasma elements and has wide-ranging consequences, including the conversion of magnetic energy into other forms and the acceleration of particles by a variety of mechanisms. A series of numerical experiments have recently stimulated a new generation of fluid theories, with current hot topics including the 3D nature of reconnection and its properties in a collisionless plasma. The applications include energy release to heat the solar corona and power solar flares and connectivity changes in flux transfer events and geomagnetic substorms in the Magnetosphere. Containing 38 papers divided into four chapters, the present volume represents the proceedings of a memorable two-day symposium held during the COSPAR General Assembly on the theory and applications of reconnection in the Sun's corona and Earth's magnetosphere.
Download or read book Hybrid Model of Magnetic Reconnection in Earth Magnetosphere written by 黃子娟 and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Studies of Magnetic Reconnection in 3D Geometries written by Arturs Vrublevskis and published by . This book was released on 2014 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic reconnection is an important and prevalent plasma physics phenomenon occurring in astrophysical (solar flares), space (magnetospheric substorms), and laboratory settings (tokamak sawtooth oscillations). It allows for a change in the magnetic field topology in plasmas while also transferring the magnetic field energy to plasma energy. In return, the global magnetic field topology can affect the dynamics of reconnection. Major advances have been made in understanding reconnection in two dimensions, which, however, are not necessarily applicable to fully three dimensional settings. We aim to add to the fundamental understanding of reconnection in three dimensions through observations in controlled laboratory experiments. To that effect we constructed and characterized an experimental setup at the Versatile Toroidal Facility that includes a washer plasma gun and a suite of diagnostics. We pulse a coil that drives reconnection along an X-line and also forms magnetic nulls in the plasma. We theoretically and experimentally investigated the relevant magnetic field configurations of a current coil in a background magnetic field. Notably, a coil tilted with respect to the background field produces nested separatrix surfaces consisting of field lines that encircle the null coil a certain number of times. The results are, to the best of our knowledge, original and contain features of relevance to the interaction of the Earth's magnetic field with the interplanetary magnetic field. In addition, we observed diamagnetic currents near the null points and magnetic reconnection along the X-line. The effective resistivity of the current sheet is significantly larger than the classical Spitzer resistivity. Thus, the observed reconnection cannot be explained as Sweet-Parker reconnection mediated by the classical resistivity. The reconnection current sheet extends to an azimuthal current sheet around the plasma beam. The azimuthal current sheet also is consistent with diamagnetic currents.
Download or read book The THEMIS Mission written by James L. Burch and published by Springer Science & Business Media. This book was released on 2009-03-03 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: J.L. Burch·V. Angelopoulos Originally published in the journal Space Science Reviews, Volume 141, Nos 1–4, 1–3. DOI: 10.1007/s11214-008-9474-5 © Springer Science+Business Media B.V. 2008 The Earth, like all the other planets, is continuously bombarded by the solar wind, which is variable on many time scales owing to its connection to the activity of the Sun. But the Earth is unique among planets because its atmosphere, magnetic eld, and rotation rates are each signi cant, though not dominant, players in the formation of its magnetosphere and its reaction to solar-wind inputs. An intriguing fact is that no matter what the time scale of solar-wind variations, the Earth’s response has a de nite pattern lasting a few hours. Known as a magnetospheric substorm, the response involves a build-up, a crash, and a recovery. The build-up (known as the growth phase) occurs because of an interlinking of the geom- netic eld and the solar-wind magnetic eld known as magnetic reconnection, which leads to storage of increasing amounts of magnetic energy and stress in the tail of the mag- tosphere and lasts about a half hour. The crash (known as the expansion phase) occurs when the increased magnetic energy and stresses are impulsively relieved, the current system that supports the stretched out magnetic tail is diverted into the ionosphere, and bright, dynamic displays of the aurora appear in the upper atmosphere. The expansion and subsequent rec- ery phases result from a second magnetic reconnection event that decouples the solar-wind and geomagnetic elds.
Download or read book The Nature of Magnetic Reconnection at the Dayside Magnetopause written by Colin Michael Komar and published by . This book was released on 2014 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt:
