Download or read book Use of a Phase sensitive Backscatter Sounder to Deduce Ionospheric Changes Associated with a Solar Flare written by Stanford University. Stanford Electronics Laboratories and published by . This book was released on 1961 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of Solar Flare Effects and Other Ionospheric Disturbances with a High Frequency Doppler Technique written by Vaughan Agy and published by . This book was released on 1965 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ionospheric Effects of Solar Flares written by Hermine Vloemans and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sudden Ionospheric Disturbances resulting from an interaction of the Solar Flare radiation with the constituents of the upper atmosphere constitute one of the three major aspects of ground level monitoring of solar flares -the other two being optical observations of flares, and the observations of solar bursts in radio wavelengths. SIDs, therefore, form a major part of flare monitoring programme in many observatories. Unlike the other two, however, the ionospheric effects of flares provide one major additional source of interest - the reaction of the ionospheric plasma to an impulsive ionization. The high atmosphere provides a low pressure laboratory without walls in which a host of reactions occur between electrons, ions and neutral particles. The resulting products and their distributions may bear no resemblance to those of the primary neutral constituents or their direct ionization products. The variations with the time of the day, with season and with solar activity that form the bulk of the ionospheric measurements are too slow to allow any insight into the nature of these ionospheric reactions whose lifetimes are often very short. The relaxation time of the ionospheric ionization is only a few minutes or fraction of a minute in the lower ionosphere and in the E-region and is about 30 min to an hour at 300 km. The flares provide a sudden short impulse comparable to these time scales.
Download or read book Ionospheric Effects of Solar Flares written by Hermine Vloemans and published by Springer. This book was released on 2012-01-07 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sudden Ionospheric Disturbances resulting from an interaction of the Solar Flare radiation with the constituents of the upper atmosphere constitute one of the three major aspects of ground level monitoring of solar flares -the other two being optical observations of flares, and the observations of solar bursts in radio wavelengths. SIDs, therefore, form a major part of flare monitoring programme in many observatories. Unlike the other two, however, the ionospheric effects of flares provide one major additional source of interest - the reaction of the ionospheric plasma to an impulsive ionization. The high atmosphere provides a low pressure laboratory without walls in which a host of reactions occur between electrons, ions and neutral particles. The resulting products and their distributions may bear no resemblance to those of the primary neutral constituents or their direct ionization products. The variations with the time of the day, with season and with solar activity that form the bulk of the ionospheric measurements are too slow to allow any insight into the nature of these ionospheric reactions whose lifetimes are often very short. The relaxation time of the ionospheric ionization is only a few minutes or fraction of a minute in the lower ionosphere and in the E-region and is about 30 min to an hour at 300 km. The flares provide a sudden short impulse comparable to these time scales.
Download or read book An Analysis of Sudden Ionospheric Disturbances Associated with the Proton Flare of 0026 UT July 7 1966 written by Richard Frank Donnelly and published by . This book was released on 1968 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ionospheric Perturbations Solar Flares and Geomagnetic Storms correlations Observed by Oblique Long range High frequency Probing written by Helen R. Baker and published by . This book was released on 1964 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Extreme Ultraviolet Flashes of Solar Flares written by Richard Frank Donnelly and published by . This book was released on 1970 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Analysis of Sudden Ionospheric Disturbances Associated with the Proton Flare of 1522 UT August 28 1966 written by Richard Frank Donnelly and published by . This book was released on 1968 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observations on Solar Flares written by John T. Jefferies and published by . This book was released on 1965 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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).
Download or read book A Review of Some Ionospheric Studies Based on a High frequency Doppler Technique written by and published by . This book was released on 1968 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physical Processes in Solar Flares written by B.V. Somov and published by Springer Science & Business Media. This book was released on 1991-12-31 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solar flares are very complex electromagnetic phenomena of a cataclysmic nature. Particles are accelerated to very high velocities and a variety of physical processes happen inside and outside flares. These processes can be studied by a large number of techniques from Earth and from space. The aim is to discover the physics behind solar flares. This goal is complicated because information about the flare mechanism can be obtained only in an indirect way by studying the secondary effects. This book provides three stages in the solution of the solar flare problem. Chapter one describes the connection between observational data and theoretical concepts, where it is stressed that next to investigating flares, the related non-stationary large-scale phenomena must be studied as well. The second chapter deals with secondary physical processes, in particular the study of high-temperature plasma dynamics during impulsive heating. The last chapter presents a model built on the knowledge of the two previous chapters and it constructs a theory of non-neutral turbulent current sheets. The author believes that this model will help to solve the problem of solar flares. For solar physicists, plasma physicists, high-energy particle physicists.
Download or read book Solar Flares written by Zdenek Svestka and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the first part of the originally planned publication by Z. Svestka and L. D. de Feiter 'Solar High Energy Photon and Particle Emission'. The second part, with the original title, was to be published by de Feiter in about one year from now. However, to the deep sorrow of all of us, Dr de Feiter died suddenly and unexpectedly when the present book was in print. Thus, unfortunately, de Feiter's second part may not appear. Due to the fact that the originally planned publication was divided into two parts, the present book is mainly descriptive and concerned with the flare morphology. It was expected that theoretical interpretations would be extensively developed in the second part, prepared by de Feiter. In particular, this refers to the theoretical back grounds of radio emissions, particle acceleration and particle propagation in space. Only in Chapter II, concerning the 'low-temperature' flare, do we go deeper into the theoretical interpretations, anticipating that de Feiter would have been concerned mainly with the 'high-energy' physics. Still, the book includes discussions on all important aspects of flares and thus can present the reader with a complete picture of the complex flare phenomenon. It is clear that many observed data on flares can be interpreted in different ways.
Download or read book An Investigation of the Effects of Solar Flares and Stratospheric Warmings on the Lower Ionosphere written by J. N. Rowe and published by . This book was released on 1970-01-01 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work a number of studies are made of D-region electron density profiles measured by the wave interaction technique at The Pennsylvania State University. Changes in electron density observed during a solar flare on October 21, 1968 are analyzed to determine an upper limit to the nitric oxide concentration. This limit is about 30,000,000 per cc at 80 kilometers. This result is then applied to the normal diurnal variation of electron density, and it is shown that the diurnal variation is consistent with this value of NO. Some electron density measurements during a stratospheric warming are also presented. (Author).
Download or read book Chromospheric and Photospheric Evolution of an Extremely Active Solar Region in Solar Cycle 19 written by Susan M. P. McKenna-Lawlor and published by . This book was released on 1981 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive investigation was made of phenomena attending the disk passage, July 7 to 21, 1959, of active solar center HAO-59Q. At the photospheric level that comprised an aggregate of groups of sunspots of which one group, Mt. Wilson 14284, showed all the attributes deemed typical of solar regions associated with the production of major flares. A special characteristic of 59Q was its capability to eject dark material. Part of this material remained trapped in the strong magnetic fields above group 14284 where it formed a system of interrelated arches, the legs of which passed through components of the bright chromospheric network of the plage and were rooted in various underlying umbrae. Two apparently diffeent kinds of flare were identified in 59Q; namely, prominence flares (which comprised brightenings within part of the suspended dark prominence) and plage flares (which comprised brightenings within part of the chromospheric network). Prominence flares were of three varieties described as 'impact', 'stationary' and 'moving' prominence flares. Plage flares were accompanied in 3 percent of cases by Type III bursts. These latter radio events indicate the associated passage through the corona of energetic electrons in the approximate energy range 10 to 100 keV. At least 87.5 percent, and probably all, impulsive brightenings in 59Q began directly above minor spots, many of which satellites to major umbrae. Stationary and moving prominence flares were individually triggered at sites beneath which magnetic changes occurred within intervals which included each flare's flash phase.
Download or read book Solar Flare Effects and Vlf Radio Wave Observations of the Lower Ionosphere written by B. Burgess and published by . This book was released on 1967 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: The observed changes of phase and signal amplitude of VLF radio waves, propagated over distances varying between 1000 and 10000 km, which accompany solar flares have been studied for the period 1961-1964. In general the phase of the received signal advances and the signal amplitude increases during the onset of a solar flare. However observations of the GBR transmissions at Rome (1500 km path) show that for this particular path the phase of the received signal retards in contrast to all other paths studied. Assuming that the conductivity of the lower ionosphere varies exponentially with height under both quiet and disturbed conditions, it is possible to evaluate the waveguide mode characteristics of VLF propagation over large distances. Using this theoretical approach it has been shown that the observations can only be interpreted if both the D region electron density profile is lowered and the gradient of ionisation density increased. The magnitude of the flare produced changes in ionisation density profiles of the lower ionosphere have been evaluated analytically from solar X-ray data. These profile changes are consistent with the lowering of the D region and increase in ionisation gradient that is required to explain the VLF radio wave observations. (Author).
Download or read book The Ionospheric Response to Solar Flares I Effects of Approximations of Solar Flare EUV Fluxes written by Elaine S. Oran and published by . This book was released on 1981 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: SOLRAD and many other satellite systems have provided a large data base showing the time-dependent behavior of broad and band solar fluxes in the X-ray and EUV spectral regions. These bands are broad in the sense that one band may contain many ionospherically important spectral lines. We present results of tests performed to determine how this information can be best be used to predict the effects of a solar flare on the ionosphere. Our approach has been to first adopt a model of the spectral line and continuum enhancements based on a synthesis of many types of flare observations. This detailed spectral model is used in a time-dependent ionosphere model to calculate the response of the electron and ion density profiles. Then the spectral model is mathematically filtered to show how it would appear to the SOLRAD EUV detectors, and this degraded information is used in the ionosphere model. Comparison of the two ionosphere shows that the two spectra produces changes in the total electron content in the ionosphere that differ by only a few percent. More significant changes which occur in the individual species densities are described. (Author).
Download or read book Abstracts of Unclassified Technical Reports written by Stanford University. Stanford Electronics Laboratories and published by . This book was released on 1963 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
