Download or read book A New Spectro Polarimeter for Solar Prominence and Filament Magnetic Field Measurements written by and published by . This book was released on 2009 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: We are constructing a spectro-polarimeter using the 4 0-cm coronagraph at the Evans Solar Facility of the National Solar Observatory in Sunspot, NM for the purpose of measuring the vector magnetic filed in prominences and filaments. The Prominence Magnetometer (ProMag) is comprised of a polarization modulation package and a spectrograph. The modulation optics are located at the prime focus of the coronagraph along with calibration optics and a beamsplitter that creates two beams of orthogonal Stokes states. The spectrograph resides at the coude focus of the coronagraph. The polarizations of the two chromospheric lines of neutral helium, at 587.6 cm and 1083.0 nm, are to be observed simultaneously. We present details of the design of the spectro-polarimeter.
Download or read book Solar Prominences written by Jean-Claude Vial and published by Springer. This book was released on 2014-11-24 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents the latest research results on solar prominences, including new developments on e.g. chirality, fine structure, magnetism, diagnostic tools and relevant solar plasma physics. In 1875 solar prominences, as seen out of the solar limb, were described by P.A. Secchi in his book Le Soleil as "gigantic pink or peach-flower coloured flames". The development of spectroscopy, coronagraphy and polarimetry brought tremendous observational advances in the twentieth century. The authors present and discuss exciting new challenges (resulting from observations made by space and ground-based telescopes in the 1990s and the first decade of the 21st century) concerning the diagnostics of prominences, their formation, their life time and their eruption along with their impact in the heliosphere (including the Earth). The book starts with a general introduction of the prominence “object” with some historical background on observations and instrumentation. In the next chapter, the various forms of prominences are described with a thorough attempt of classification. Their thermodynamic (and velocity) properties are then derived with emphasis on the methods (and their limits) used. This goes from the simplest optically thin case to the heavy radiative treatment of plasmas out of local thermodynamic equilibrium. The following chapters are devoted to the magnetic field measurements and indirect derivation. A new branch of diagnostic tools, the seismology, is presented along with some MHD basics. This allows to better understand the propagation of waves, the energy and force equilibria. Both small-scale and large-scale studies and their relationship are presented. The importance of the newly discovered cavities is stressed in the context of prominence destabilization. The issues of prominence formation and eruption, their connection with flares and Coronal Mass Ejections and their impact on the Earth are addressed on the basis of the latest results. Finally, an exciting new area of research is unveiled with the newly discovered evidence of similar manifestations in the Universe and their possible impact on the habitability of exoplanets. References to the basic physics (where necessary) are provided and the proposed web sites addresses will allow the reader to load exciting movies. The book is aimed at advanced students in astrophysics, post-graduates, solar physicists and more generally astrophysicists. Amateurs will enjoy the many new images which go with the text.
Download or read book Polarimetric Studies of the Solar Atmosphere written by Sanjay Gosain and published by LAP Lambert Academic Publishing. This book was released on 2010-09 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the design and development of an instrument called the Solar Vector Magnetograph or SVM. This instrument maps the magnetic field of the solar active regions. The magnetic field of solar active regions is responsible for the eruptive phenomena on the sun which expel large amounts of high-energy particles and radiation in the interplanetary space posing danger for human activities in space. The careful measurement of solar magnetic field is very important to track its evolution which may be useful for forecasting the solar eruptive events. The instrument SVM was developed by Dr. Sanjay Gosain during his Ph.D. at Udaipur Solar Observatory, India for which he received best thesis award by Astronomical Society of India. This book describes how the high-cadence magnetic field measurements can be done by using a tunable Fabry-Perot etalon and a polarimeter. This book is useful for any solar astronomer who wishes to develop an instrument for measuring solar magnetic fields or wishes to understand how solar magnetic field is measured using Zeeman-effect diagnostics. The techniques of optical polarimetry is also discussed in depth.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1987 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1987 Part 1 written by S. Böhme and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1300 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 ...... .
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1974 with total page 1756 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polarization in Spectral Lines written by M. Landi Degl'Innocenti and published by Springer Science & Business Media. This book was released on 2006-05-17 with total page 899 pages. Available in PDF, EPUB and Kindle. Book excerpt: The scientific research based on spectropolarimetric techniques is undergoing a phase of rapid growth. Instruments of unprecedented sensitivity are nowadays available, particularly for solar observations. To fully exploit the rich diagnostic content of such observations, it is necessary to understand the physical mechanisms involved in the generation and transfer of polarized radiation in astrophysical (or laboratory) plasmas. After an introductory part based on classical physics, this book tackles the subject by a rigorous quantum-mechanical approach. The transfer equations for polarized radiation and the statistical equilibrium equations for the atomic density matrix are derived directly from the principles of Quantum Electrodynamics. The two sets of equations are then used to present a number of applications, mainly concerning the diagnostics of solar magnetic fields. This book is primarily addressed to scientists working in the field of spectropolarimetry. It may also serve as a textbook for a course at the graduate or advanced undergraduate level.
Download or read book Solar Polarimetry written by Lawrence J. November and published by . This book was released on 1991 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Magnetohydrodynamics of the Sun written by Eric Priest and published by Cambridge University Press. This book was released on 2014-04-07 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetohydrodynamics of the Sun is a completely new up-to-date rewrite from scratch of the 1982 book Solar Magnetohydrodynamics, taking account of enormous advances in understanding since that date. It describes the subtle and complex interaction between the Sun's plasma atmosphere and its magnetic field, which is responsible for many fascinating dynamic phenomena. Chapters cover the generation of the Sun's magnetic field by dynamo action, magnetoconvection and the nature of photospheric flux tubes such as sunspots, the heating of the outer atmosphere by waves or reconnection, the structure of prominences, the nature of eruptive instability and magnetic reconnection in solar flares and coronal mass ejections, and the acceleration of the solar wind by reconnection or wave-turbulence. It is essential reading for graduate students and researchers in solar physics and related fields of astronomy, plasma physics and fluid dynamics. Problem sets and other resources are available at www.cambridge.org/9780521854719.
Download or read book Advanced Solar Polarimetry written by National Solar Observatory/Sacramento Peak. Summer Workshop and published by . This book was released on 2001 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation This proceedings volume of the September 2000 workshop presents recent developments in spectropolarimetry and the measurement of solar magnetic fields using the Zeeman and Hanle effects. The 67 papers address new instrumentation for telescopes, weak polarization and coronal magnetic fields, infrared polarimetry and the physics of active regions, magnetohydrodynamic (MHD) simulations, high resolutions polarimetry and the physics of flux tubes, and the analysis of Stokes profiles. No subject index. Annotation c. Book News, Inc., Portland, OR (booknews.com)
Download or read book Coronal Magnetometry written by Sarah E. Gibson and published by Frontiers Media SA. This book was released on 2017-07-11 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetism defines the complex and dynamic solar corona. It determines the magnetic loop structure that dominates images of the corona, and stores the energy necessary to drive coronal eruptive phenomena and flare explosions. At great heights the corona transitions into the ever-outflowing solar wind, whose speed and three-dimensional morphology are controlled by the global coronal magnetic field. Coronal magnetism is thus at the heart of any understanding of the nature of the corona, and essential for predictive capability of how the Sun affects the Earth. Coronal magnetometry is a subject that requires a concerted effort to draw together the different strands of research happening around the world. Each method provides some information about the field, but none of them can be used to determine the full 3D field structure in the full volume of the corona. Thus, we need to combine them to understand the full picture. The purpose of this Frontiers Research Topic on Coronal Magnetometry is to provide a forum for comparing and coordinating these research methods, and for discussing future opportunities.
Download or read book Solar Flare Magnetic Fields and Plasmas written by Yuhong Fan and published by Springer Science & Business Media. This book was released on 2012-03-28 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is devoted to the dynamics and diagnostics of solar magnetic fields and plasmas in the Sun’s atmosphere. Five broad areas of current research in Solar Physics are presented: (1) New techniques for incorporating radiation transfer effects into three-dimensional magnetohydrodynamic models of the solar interior and atmosphere, (2) The connection between observed radiation processes occurring during flares and the underlying flare energy release and transport mechanisms, (3) The global balance of forces and momenta that occur during flares, (4) The data-analysis and theoretical tools needed to understand and assimilate vector magnetogram observations and (5) Connecting flare and CME phenomena to the topological properties of the magnetic field in the Solar Atmosphere. The role of the Sun’s magnetic field is a major emphasis of this book, which was inspired by a workshop honoring Richard C. (Dick) Canfield. Dick has been making profound contributions to these areas of research over a long and productive scientific career. Many of the articles in this topical issue were first presented as talks during this workshop and represent substantial original work. The workshop was held 9 – 11 August 2010, at the Center Green campus of the National Center for Atmospheric Research (NCAR) in Boulder, Colorado. This volume is aimed at researchers and graduate students active in solar physics, solar-terrestrial physics and magneto-hydrodynamics. Previously published in Solar Physics journal, Vol. 277/1, 2012.
Download or read book The Nature of Solar Prominences written by Einar Tandberg-Hanssen and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 315 pages. Available in PDF, EPUB and Kindle. Book excerpt: "He is beautiful and radiant with great splendor ... " St. Francis, from Cantico del sole Two decades have elapsed since the publication of Solar Prominences, 20 years that have seen a nearly phenomenal increase in the interest, as well as the infor mation, concerning these fascinating and beautiful manifestations of solar ac tivity. During this period many meetings have been held, and several books and proceedings have been published, all dealing with specific aspects of solar prominences. However, no unifying and comprehensive accord has appeared. Recently some of my colleagues suggested that the time was ripe for a new addition of Solar Prominences, and Kluwer Academic Publishers wanted to pub lish such a book. I, therefore, venture to present this monograph in the hope of kindling the interest of some graduate students in the study of this-probably the most spectacular and often the most beautiful of solar activity manifestation. However, since it is the physical processes behind these events that will particu larly interest us, I also hope the book may be of help to some of my colleagues. In a rapidly developing field of science it is difficult, if not impossible, to present an overview that is up to date in every respect. I have made nearly every effort to include the latest contributions in the broad area of prominence research, but I am sure I have overlooked some important investigations. For these oversights, I apologize.
Download or read book Instrument Systems for Imaging Spectro Polarimetry written by Alex J. Feller and published by Cuvillier Verlag. This book was released on 2008-04-01 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is devoted to the development and the application of novel instrument systems and measuring techniques in the field of solar polarimetry. The work is split into three parts, each part addressing an independent project in terms of scientific objectives and implementation. In the first part I describe the development and implementation of a tunable narrow-band filter system to be used in combination with the Zurich Imaging Polarimeter for quasi-monochromatic imaging vector polarimetry. Its working range covers the visible spectrum between 390 nm and 660 nm. The bandwidth varies between 2 pm and 12 pm, depending on wavelength and optical setup. The main filter components are two lithium-niobate Fabry-Pérot interferometers which can be tuned by applying a voltage or by changing the temperature. In the current version of the instrument the interferometers are used in series in a single-pass tandem configuration. The filter system will allow us to explore the spatial structuring of the polarized solar spectrum, including vector mapping of the Hanle and Zeeman effects in any spectral line. First polarimetric images recorded at the SST and at IRSOL in the spectral lines of Ca I 422.7 nm, Sr I 460.7 nm and Hα 656.3 nm show that the instrumentation and its operation is technically mature. The filter system is now available for scientific observations. The second part deals with a laboratory experiment linked to a solar polarization anomaly that has remained an unresolved enigma for many years. While scattering processes usually produce polarized radiation, certain spectral lines, in particular the Fraunhofer D1line of neutral sodium at 589.6 nm should be intrinsically unpolarizable according to the standard quantum mechanical scattering theory. In contrast, observations in quiet regions on the Sun reveal a polarization peak centered in the D1 line core. As the solar atmosphere is a complex environment with an optically thick medium permeated by a tangled and fractal-like magnetic field, we have set up a laboratory experiment with a sodium vapor cell to obtain an answer to the question: Is the sodium D1 anomaly a problem for atomic or for solar physics? The experimental results are consistent with the theoretical null prediction of atomic physics. Furthermore the experiment gives an upper limit for the D1 polarization which is smaller than the signal observed on the Sun. Although this result does not provide the definitive answer to the problem, it permits to conclude that the clarification of the D1 anomaly has to involve solar physics. The third project included in this thesis is the development of a dedicated instrument to capture the polarization of the chromospheric emission spectrum (flash spectrum) during the total solar eclipse of March 29, 2006. The whole visible range and small overlaps with near UV and near IR have been covered with a spectral resolution of 3000. The minimum sampling period was chosen to be 20 ms, which corresponds to a height resolution of some 10 km in the solar atmosphere, along the direction of the lunar movement. The flash spectrum has been successfully recorded during the above-mentioned eclipse in the Sahara desert in southern Libya. For several spectral lines the noise level in the degree of polarization is of order 1% which allows us to compare with theoretical predictions. However, it is tricky to correct for the systematic errors because of optical aberrations in the observed spectra.
Download or read book Physics of the Solar Corona written by Markus Aschwanden and published by Springer Science & Business Media. This book was released on 2006-01-30 with total page 946 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book The Origin and Dynamics of Solar Magnetism written by M.J. Thompson and published by Springer Science & Business Media. This book was released on 2009-05-01 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: Starting in 1995 numerical modeling of the Earth’s dynamo has ourished with remarkable success. Direct numerical simulation of convection-driven MHD- ow in a rotating spherical shell show magnetic elds that resemble the geomagnetic eld in many respects: they are dominated by the axial dipole of approximately the right strength, they show spatial power spectra similar to that of Earth, and the magnetic eld morphology and the temporal var- tion of the eld resembles that of the geomagnetic eld (Christensen and Wicht 2007). Some models show stochastic dipole reversals whose details agree with what has been inferred from paleomagnetic data (Glatzmaier and Roberts 1995; Kutzner and Christensen 2002; Wicht 2005). While these models represent direct numerical simulations of the fundamental MHD equations without parameterized induction effects, they do not match actual pla- tary conditions in a number of respects. Speci cally, they rotate too slowly, are much less turbulent, and use a viscosity and thermal diffusivity that is far too large in comparison to magnetic diffusivity. Because of these discrepancies, the success of geodynamo models may seem surprising. In order to better understand the extent to which the models are applicable to planetary dynamos, scaling laws that relate basic properties of the dynamo to the fundamental control parameters play an important role. In recent years rst attempts have been made to derive such scaling laws from a set of numerical simulations that span the accessible parameter space (Christensen and Tilgner 2004; Christensen and Aubert 2006).
