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Meteorology
Published in David House, Seamanship Techniques, 2019
This shimmering area of light is caused by an electrical discharge in the atmosphere over high northern and southern latitudes. The Northern Lights are called the Aurora Borealis, and the Southern Lights the Aurora Australis.
Air Pollution
Published in William J. Rea, Kalpana D. Patel, Air Pollution and the Electromagnetic Phenomena as Incitants, 2018
William J. Rea, Kalpana D. Patel
The aurora, or northern and southern lights, are often visible from the surface of the earth at high northern and southern latitudes. Auroras typically appear as luminous bands or streamers that can extend to altitudes of 200 miles, well into the ionosphere. Auroras are caused by high-energy particles from the solar wind that is trapped in the earth's magnetic field. The collision of trapped particles with atmospheric molecules causes spectacular effects in the visible spectrum, but these excited molecules can also emit radiation in other wavelength bands like ultraviolet, x-ray, and so on. If any of these electric and magnetic phenomena get into the earth's atmosphere, they will affect the chemically and electrically sensitive and chronic degenerative diseased patient.9
Symbols, Terminology, and Nomenclature
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Auger effect - An atomic process in which an electron from a higher energy level fills a vacancy in an inner shell, transferring the released energy to another electron which is ejected. Aurora - An atmospheric phenomenon in which streamers of light are produced when electrons from the sun are guided into the thermosphere by the earth's magnetic field. It occurs in the polar regions at altitudes of 95--300 km. Avogadro constant (NA)* - The number of elementary entities in one mole of a substance. Azeotrope - A liquid mixture in a state where the variation of vapor pressure with composition at constant temperature (or, alternatively, the variation of normal boiling point with composition) shows either a maximum or a minimum. Thus when an azeotrope boils the vapor has the same composition as the liquid. Azides - Compounds bearing the group -N3, viz. -N=N+=N-; usually attached to carbon, e.g. PhN3, phenyl azide or azidobenzene. Also used for salts of hydrazoic acid, HN3, e.g. NaN3, sodium azide. [5] Azines - Condensation products, R2C=NN=CR2 , of two moles of a carbonyl compound with one mole of hydrazine. [5] Azo compounds - Derivatives of diazene (diimide), HN=NH, wherein both hydrogens are substituted by hydrocarbyl groups, e.g., PhN=NPh, azobenzene or diphenyldiazene. [5] Balmer series - The series of lines in the spectrum of the hydrogen atom which corresponds to transitions between the state with principal quantum number n = 2 and successive higher states. The wavelengths are given by 1/ = RH(1/4 - 1/n2), where n = 3,4,... and RH is the Rydberg constant for hydrogen. The first member of the series (n = 2 3), which is often called the H line, falls at a wavelength of 6563 Å. Bar (bar) - A unit of pressure equal to 105 Pa.' Bardeen-Cooper-Schrieffer (BCS) theory - A theory of superconductivity which is based upon the formation of electron pairs as a result of an electron-lattice interaction. The theory relates the superconducting transition temperature to the density of states and the Debye temperature. Barn (b) - A unit used for expressing cross sections of nuclear processes, equal to 10-28 m2. Barrel - A unit of volume equal to 158.9873 L. Baryon - Any elementary particle built up from three quarks. Examples are the proton, neutron, and various short-lived hyperons. Baryons have odd half-integer spins. Base - Historically, a substance that yields an OH- ion when it dissociates in solution, resulting in a pH>7. In the Brönsted definition, a base is a substance capable of accepting a proton in any type of reaction. The more general definition, due to G.N. Lewis, classifies any chemical species capable of donating an electron pair as a base. Becquerel (Bq)* - The SI unit of radioactivity (disintegrations per unit time), equal to s-1. [1] Beer's law - An approximate expression for the change in intensity of a light beam that passes through an absorbing medium, viz., log(I/I0) = -cl, where I0 is the incident intensity, I is the final intensity, is the molar (decadic) absorption coefficient, c is the molar concentration of the absorbing substance, and l is the path length. Also called the Beer-Lambert law Binding energy* - A generic term for the energy required to decompose a system into two or more of its constituent parts. In nuclear physics, the binding energy is the energy differ-
Novel acousto-optical tunable filter (AOTF) based spectropolarimeter for the characterization of auroral emission
Published in Instrumentation Science & Technology, 2021
Jurgen Vanhamel, Emmanuel Dekemper, Sophie Berkenbosch, Roland Clairquin
Northern lights are a beautiful manifestation of the solar-terrestrial coupling. Produced by the interaction of solar particles with the nitrogen and oxygen atoms in the thermosphere, auroras shine at discrete optical wavelengths corresponding to the electronic transitions which give them birth. The auroral light has a certain level of polarization, which is useful in the frame of predicting space weather[1] or to characterize the atmosphere as a response to particle precipitations.[2]
Coexistence of positive and negative polarity solitons, double layers and supersolitons in electron-positron multi-ion plasmas
Published in Waves in Random and Complex Media, 2023
Debaditya Kolay, Debjit Dutta, Biswajit Sahu
A four-component multi-ion plasma made up of inertial light positive ions, heavy negative ions, inertialess nonextensive electrons, and positrons has been taken into consideration. In the beginning, we have analytically derived the Sagdeev Pseudopotential and then numerically investigated the existence of several nonlinear structures such as solitons, double layers, and supersolitons. Investigating numerically, it is found that the usual soliton, flat-top soliton, double layer, and supersoliton structures exist in our plasma model for a certain range of parameters. We derived the existence region in the parameter space for both soliton and supersoliton structures, by determining the specific limitation of the model in a systematic way. As a result of the investigation, both negative and positive potential solitary wave structures are found to be present in our multi-species e-p-i plasma and their region of coexistence has been derived. Physically, the possibility of getting a range of parameters which supports the finite soliton at acoustic velocity is characterized by the notion of co-existence. On the other hand, the development of double layers ought to aid in understanding possible causes of energetic particle acceleration in different astrophysical e-p-i plasma system. A potential decrease in the layers and a disappearing electric field on either side of the layer are caused by two parallel layers of opposite charge that creates the double layer. A plasma system releases a certain amount of energy due to the formation of double layers, which accelerates the charged particles of the system. The accelerated electrons have been observed in a narrow region above the Earth's ionosphere and this acceleration is possibly caused by the formation of several double layers in that region. The particle acceleration phenomenon in the auroral zone of the atmosphere occurs due to the double layers that are frequently produced in the Earth's magnetosphere. On the other hand, neither laboratory plasmas nor space plasmas have any direct evidence of supersolitons [75]. However, additional measurements of the electric field made by satellite expeditions [67,76] in space plasma conditions may be able to identify the signature of positive potential supersolitons. In this situation, present research will contribute some new data regarding the existence of supersolitons to the current information on nonlinear wave propagation in plasmas. The distinction between ‘KdV-like’ and ‘non-KdV-like’ solitons(of opposite polarity) has been established for our plasma model.