Solar Flare Loops Observations And Interpretations

Author : Guangli Huang,Victor F. Melnikov,Haisheng Ji,Zongjun Ning
Publisher : Springer
Page : 424 pages
File Size : 42,8 Mb
Release : 2018-01-31
Category : Science
ISBN : 9789811028694

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Solar Flare Loops: Observations and Interpretations by Guangli Huang,Victor F. Melnikov,Haisheng Ji,Zongjun Ning Pdf

This book provides results of analysis of typical solar events, statistical analysis, the diagnostics of energetic electrons and magnetic field, as well as the global behavior of solar flaring loops such as their contraction and expansion. It pays particular attention to analyzing solar flare loops with microwave, hard X-ray, optical and EUV emissions, as well as the theories of their radiation, and electron acceleration/transport. The results concerning influence of the pitch-angle anisotropy of non-thermal electrons on their microwave and hard X-ray emissions, new spectral behaviors in X-ray and microwave bands, and results related to the contraction of flaring loops, are widely discussed in the literature of solar physics. The book is useful for graduate students and researchers in solar and space physics.

Author : John T. Jefferies
Publisher : Unknown
Page : 56 pages
File Size : 53,7 Mb
Release : 1965
Category : Electromagnetism
ISBN : UOM:39015095127224

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Observations on Solar Flares by John T. Jefferies Pdf

Various aspects of solar flares such as dynamic phenomena, the relation to magnetic fields, electromagnetic radiations, particle emissions, and flare loops are discussed with attempts at classification in terms of observable effects. Discrepancies in defining the mechanisms that must exist stress the need for further observations. (Author).

Author : Jun-Ichi Sakai,C. de Jager
Publisher : Springer Science & Business Media
Page : 198 pages
File Size : 40,7 Mb
Release : 2012-12-06
Category : Science
ISBN : 9789400903319

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Solar Flares and Collisions between Current-Carrying Loops by Jun-Ichi Sakai,C. de Jager Pdf

In this volume we compare modem observations of solar flares with results from recent theoretical research and simulation studies on current-carrying loops and their interaction. These topics have undergone rapid developments in the course of recent years. Observational results by X-ray monitoring and imaging spacecraft in the seventies and by dedicated imaging instrumentation in the satellites Solar Max imum Mission and Hinotori, launched 1980 and 1981, have shown the importance of X-ray imaging for understanding the ignition processes of solar flares. Such observations, in tum, stimulated theoretical studies, centered around the flux-tube concept. The classical idea that flares originate by interaction of current-carrying loops was developed and proved to be promising. Concepts on reconnection and coalescence of flux tubes were developed, and their consequences studied. The Yohkoh spacecraft, launched 1991, showed the overwhelming importance of coro nal flux tubes and their many possible ways of interaction. Subsequent and parallel theoretical studies and simulations, differentiating between the topology of interact ing fluxtubes, demonstrated that the mutual positioning and the way of interaction are important for the subsequent processes of energy release in flares and the many associated phenomena such as the expUlsion of jets and the emission of X -ray and microwave radiation. The new developments now enable researchers to understand and classify flares in a physically significant way. Various processes of accelera tion are active in and after flares on greatly varying timescales; these can now be distinguished and explained.

Author : Jun-Ichi Sakai,C. de Jager
Publisher : Springer
Page : 192 pages
File Size : 48,7 Mb
Release : 2011-10-13
Category : Science
ISBN : 9400903324

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Solar Flares and Collisions between Current-Carrying Loops by Jun-Ichi Sakai,C. de Jager Pdf

In this volume we compare modem observations of solar flares with results from recent theoretical research and simulation studies on current-carrying loops and their interaction. These topics have undergone rapid developments in the course of recent years. Observational results by X-ray monitoring and imaging spacecraft in the seventies and by dedicated imaging instrumentation in the satellites Solar Max imum Mission and Hinotori, launched 1980 and 1981, have shown the importance of X-ray imaging for understanding the ignition processes of solar flares. Such observations, in tum, stimulated theoretical studies, centered around the flux-tube concept. The classical idea that flares originate by interaction of current-carrying loops was developed and proved to be promising. Concepts on reconnection and coalescence of flux tubes were developed, and their consequences studied. The Yohkoh spacecraft, launched 1991, showed the overwhelming importance of coro nal flux tubes and their many possible ways of interaction. Subsequent and parallel theoretical studies and simulations, differentiating between the topology of interact ing fluxtubes, demonstrated that the mutual positioning and the way of interaction are important for the subsequent processes of energy release in flares and the many associated phenomena such as the expUlsion of jets and the emission of X -ray and microwave radiation. The new developments now enable researchers to understand and classify flares in a physically significant way. Various processes of accelera tion are active in and after flares on greatly varying timescales; these can now be distinguished and explained.

Author : R. J. Bray
Publisher : Cambridge University Press
Page : 524 pages
File Size : 52,5 Mb
Release : 1991-07-18
Category : Science
ISBN : 9780521351072

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Plasma Loops in the Solar Corona by R. J. Bray Pdf

A comprehensive account of the properties of plasma loops, the fundamental structural elements of the solar corona. Plasma loops cover a wide range of sizes and range in temperature from tens of thousands to millions of degrees. They not only define the structure of individual active regions but connect different active regions--even across the solar equator. Loops also play an integral and decisive role in the enormous solar explosions called flares. Over recent years a wealth of space and ground-based observations of loops has been obtained in various widely-spaced regions of the electromagnetic spectrum. In this book the authors have selected the best observational material from the literature on which to base a detailed account of the properties of flare and non-flare loops. The book also explores the larger implications of the loop structures for our understanding of solar and stellar coronae. The text is enhanced by a large number of illustrations and unique and beautiful photographs obtained from the ground and from space.

Author : Markus Aschwanden
Publisher : Springer Science & Business Media
Page : 233 pages
File Size : 41,6 Mb
Release : 2013-03-09
Category : Science
ISBN : 9789401725415

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Particle Acceleration and Kinematics in Solar Flares by Markus Aschwanden Pdf

Over the last decade we entered a new exploration phase of solar flare physics, equipped with powerful spacecraft such as Yohkoh, SoHO, and TRACE that pro vide us detail-rich and high-resolution images of solar flares in soft X-rays, hard X -rays, and extreme-ultraviolet wavelengths. Moreover, the large-area and high sensitivity detectors on the Compton GRO spacecraft recorded an unprecedented number of high-energy photons from solar flares that surpasses all detected high energy sources taken together from the rest of the universe, for which CGRO was mainly designed to explore. However, morphological descriptions of these beau tiful pictures and statistical catalogs of these huge archives of solar data would not convey us much understanding of the underlying physics, if we would not set out to quantify physical parameters from these data and would not subject these measurements to theoretical models. Historically, there has always been an unsatisfactory gap between traditional astronomy that dutifully describes the mor phology of observations, and the newer approach of astrophysics, which starts with physical concepts from first principles and analyzes astronomical data with the goal to confirm or disprove theoretical models. In this review we attempt to bridge this yawning gap and aim to present the recent developments in solar flare high-energy physics from a physical point of view, structuring the observations and analysis results according to physical processes, such as particle acceleration, propagation, energy loss, kinematics, and radiation signatures.

Author : S. Böhme,W. Fricke,I. Heinrich,W. Hofmann,D. Krahn,V. R. Matas,D. Rosa,L. D. Schmadel,G. Zech
Publisher : Springer Science & Business Media
Page : 803 pages
File Size : 54,7 Mb
Release : 2013-04-18
Category : Science
ISBN : 9783662123317

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Literature 1981, Part 2 by S. Böhme,W. Fricke,I. Heinrich,W. Hofmann,D. Krahn,V. R. Matas,D. Rosa,L. D. Schmadel,G. Zech Pdf

Author : Todd Alan Gunkler
Publisher : Unknown
Page : 336 pages
File Size : 49,6 Mb
Release : 1984
Category : Astronomical spectroscopy
ISBN : UCSD:31822033914219

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Observations and Analysis of Solar Flares Using H[alpha] Spectral Profiles by Todd Alan Gunkler Pdf

Author : Markus Aschwanden
Publisher : Springer Science & Business Media
Page : 908 pages
File Size : 50,9 Mb
Release : 2006-08-26
Category : Science
ISBN : 9783540307662

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Physics of the Solar Corona by Markus Aschwanden Pdf

A thorough introduction to solar physics based on recent spacecraft observations. The author introduces the solar corona and sets it in the context of basic plasma physics before moving on to discuss plasma instabilities and plasma heating processes. The latest results on coronal heating and radiation are presented. Spectacular phenomena such as solar flares and coronal mass ejections are described in detail, together with their potential effects on the Earth.

Author : Vanessa Polito,Bart de Pontieu,Adam Kowalski,Viggo Hansteen
Publisher : Frontiers Media SA
Page : 197 pages
File Size : 46,7 Mb
Release : 2023-12-27
Category : Science
ISBN : 9782832539330

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Flare Observations in the IRIS Era: What Have We Learned, and What’s Next? by Vanessa Polito,Bart de Pontieu,Adam Kowalski,Viggo Hansteen Pdf

Since its launch in 2013, IRIS has observed more than 10 X-class, over 100 M-class and more than 600 C-class flares at unprecedented spatial and temporal resolution. Thanks to the rich diagnostics that cover the physical conditions of the solar atmosphere from the photosphere to the hottest parts of the flaring corona, IRIS observations have provided exciting new results and constraints on flare heating models, significantly expanding our knowledge of how flares are triggered, and how the non-thermal energy is released, propagates downward from the corona, and is deposited in the low atmosphere. At the same time, the new discoveries provided by IRIS have raised new unresolved questions and new challenges for theoretical models. For instance, current hydrodynamic models still cannot fully explain many features observed by IRIS during both the impulsive and gradual phases such as the dynamics of the evaporative/condensation flows, the large line broadenings, and the puzzling complex and broad chromospheric lines. In addition, important questions remain regarding the details of the energy propagation and dissipation in flares, the importance of Alfvén waves vs electron-beam and thermal conduction heating, and the effects from large-scale reconfiguration of the magnetic field during flares.

Author : S.R. Kane,Yutaka Uchida,K. Tanaka,Hugh S. Hudson
Publisher : Springer Science & Business Media
Page : 451 pages
File Size : 42,9 Mb
Release : 2012-12-06
Category : Science
ISBN : 9789400972285

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Recent Advances in the Understanding of Solar Flares by S.R. Kane,Yutaka Uchida,K. Tanaka,Hugh S. Hudson Pdf

These Proceedings result from the papers and discussions of the U.S.-Japan Seminar "Recent Advances in the Understanding of Solar Flares" held in Tokyo October 5-8, 1982. The meeting was sponsored jointly by the Japan Society for the Promotion of Science and the u.S. National Science Foundation. The principal aim of the meeting was to obtain the most up-to-date physical picture of solar flares by bringing together results from the recent observations by the Solar Maximum Mission (SMM) and HINOTORI satellites, together with other satellite data and ground-based data at both optical and radio wavelengths. These data cover the recent maximum of the solar activity cycle. The SMM and HINOTORI introduced a new dimension in flare observations by carrying out the first hard X-ray imaging observations, and the organizers especially felt that an intense discussion of the significance of these results in the context of flare theories would be important. Starting with an introductory presentation of the characteristics of the instruments on board the satellites, the sessions of the first day and the beginning of the second dealt mainly with energy transport in flares and with .the formation process of the hot plasma which is .

Author : Vladimir Evgenʹevich Stepanov,V. N. Obridko
Publisher : VSP
Page : 470 pages
File Size : 51,9 Mb
Release : 1987-12
Category : Science
ISBN : 9067640654

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Solar Maximum Analysis by Vladimir Evgenʹevich Stepanov,V. N. Obridko Pdf

These proceedings contain the review and contributed papers given at the SMY--SMA Workshop held in Irkutsk (USSR), 17--24 June 1985. The main themes of the Workshop were plasma physics and magnetohydrodynamics with applications to processes occurring in solar flares. The papers published in this volume are organized around the following topics: -- the reconnection of coronal magnetic fields as a source of flare energy -- the acceleration of particles to high energies -- the dynamics of interplanetary clouds and shocks

Author : S. Böhme,Prof. Dr. Walter Fricke,H. Hefele,Inge Heinrich,W. Hofmann,D. Krahn,V. R. Matas,Dr. Lutz D. Schmadel,G. Zech
Publisher : Springer Science & Business Media
Page : 947 pages
File Size : 54,9 Mb
Release : 2013-11-11
Category : Science
ISBN : 9783662123430

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Literature 1984, Part 1 by S. Böhme,Prof. Dr. Walter Fricke,H. Hefele,Inge Heinrich,W. Hofmann,D. Krahn,V. R. Matas,Dr. Lutz D. Schmadel,G. Zech Pdf

Author : Marina Battaglia
Publisher : Cuvillier Verlag
Page : 162 pages
File Size : 41,6 Mb
Release : 2009-02-05
Category : Science
ISBN : 9783736928800

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Particle kinematics in solar flares: observations and theory by Marina Battaglia Pdf

This thesis is devoted to the study of particle acceleration and propagation processes in solar flares. Solar flares are amongst the most powerful and energetic activity phenomena our Sun exhibits. They release energy of the order of 1032 erg in seconds to minutes. In the process, electrons and protons are accelerated to relativistic energies, making flares very efficient particle accelerators. The most compelling observational signatures of flares can be found in X-rays and extreme ultra-violet wavelengths. Due to atmospheric absorption, those wavelengths can only be studied from space. Since the beginning of the space age, countless flares have been observed by satellites. The present work is largely based on observations by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI), an X-ray satellite which has been observing the Sun since February 2002. It is a NASA mission with substantial Swiss hardware and software contribution. Using RHESSI observations of flares of different intensity, a deeper understanding of the particle transport and energy transport processes in flare loops, as well as the acceleration site and acceleration mechanism is sought. The time evolution of images and spectra is studied along with the quantitative relations between X-ray sources observed in the corona (coronal sources) and from the chromosphere (footpoints). The spectral relations found between coronal sources and footpoints are compared to the so-called ``intermediate thin-thick target model'', which was based on observations by the satellite Yohkoh. We show that the spectral relations between coronal sources and footpoints observed with RHESSI cannot be explained by the intermediate thin-thick target model. In a next step, return currents in the flare loop were considered. With this extension to the existing model, the spectra of the coronal source and the footpoints, as well as the relations between them can be explained, indicating the importance of return currents in flare loops. In a second part, observations of so-called ``pre-flares'' are presented. This earliest phase of a flare cannot be explained by the standard flare model of chromospheric evaporation which involves energy transport and deposition in the chromosphere by beams of accelerated electrons. In pre-flares, an increase in density and emission measure is observed, indicating that chromospheric evaporation is occurring. However, no observational signatures of fast electrons are found. We show that if energy is transported by means of thermal conduction instead of an electron beam, the observations can explained.

Author : S. Böhme,U. Esser,H. Hefele,I. Heinrich,W. Hofmann,D. Krahn,V. R. Matas,L. D. Schmadel,G. Zech
Publisher : Springer Science & Business Media
Page : 1300 pages
File Size : 47,6 Mb
Release : 2013-11-11
Category : Science
ISBN : 9783662123584

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Literature 1987, Part 1 by S. Böhme,U. Esser,H. Hefele,I. Heinrich,W. Hofmann,D. Krahn,V. R. Matas,L. D. Schmadel,G. Zech Pdf

Astronomy and Astrophysics Abstracts aims to present a comprehensive documen tation of the literature concerning all aspects of astronomy, astrophysics, and their border fields. It is devoted to the recording, summarizing, and indexing of the relevant publications throughout the world. Astronomy and Astrophysics Abstracts is prepared by a special department of the Astronomisches Rechen-Institut under the auspices of the International Astronomical Union. Volume 43 records literature published in 1987 and received before August 15, 1987. Some older documents which we received late and which are not surveyed in earlier volumes are included too. We acknowledge with thanks contributions of our colleagues all over the world. We also express our gratitude to all organiza tions, observatories, and publishers which provide us with complimentary copies of their publications. Starting with Volume 33, all the recording, correction, and data processing work was done by means of computers. The recording was done by our technical staff members Ms. Helga Ballmann, Ms. Beate Gobel, Ms. Monika Kohl, Ms. Sylvia Matyssek, Ms. Doris Schmitz-Braunstein, Ms. Utta-Barbara Stegemann. Mr. Jochen Heidt and Mr. Kristopher Polzine supported our task by careful proof reading. It is a pleasure to thank them all for their encouragement. Heidelberg, October 1987 The Editors Contents Introduction . . . . . . . . . . . 1 Concordance Relation: PHYS-AAA 3 Abbreviations 5 Periodicals, Proceedings, Books, Activities 001 Periodicals . . . . . . . . . . . 10 002 Bibliographical Publications, Documentation, Catalogues, Data Bases 50 003 Books ...... .