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Paschen Curves
Paschen may refer to: * Friedrich Paschen (1865–1947), German physicist ** Paschen (crater), a lunar crater on the far side of the Moon ** Paschen-Back effect, the splitting of atomic energy levels in the presence of a strong magnetic field ** Paschen series, a Hydrogen spectral series in the infrared band ** Paschen's law, an equation that gives the breakdown voltage, that is the voltage necessary to start a discharge or electric arc, between two electrodes in a gas as a function of pressure and gap length {{Disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Paschen
Louis Carl Heinrich Friedrich Paschen (22 January 1865 - 25 February 1947), was a German physicist, known for his work on electrical discharges. He is also known for the Paschen series, a series of hydrogen spectral lines in the infrared region that he first observed in 1908. He established the now widely used Paschen curve in his article ''"Über die zum Funkenübergang in Luft, Wasserstoff und Kohlensäure bei verschiedenen Drücken erforderliche Potentialdifferenz"''. He is known for the Paschen-Back effect, which is the Zeeman effect's becoming non-linear at high magnetic field. He helped explain the hollow cathode effect in 1916. Life Paschen was born in Schwerin, Mecklenburg-Schwerin. From 1884 to 1888 he studied at the universities of Berlin and Strassburg, after which he became an assistant at the Academy of Münster. He became a professor at the Technical Academy of Hannover in 1893 and professor of physics at the University of Tübingen in 1901. He served as presiden ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paschen (crater)
Paschen is a lunar impact crater on the far side of the Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of .... The relatively large satellite crater Paschen M partly overlies the southern rim of Paschen, and they nearly form a merged pair with only a section of irregular terrain along their common border. The smaller but well-formed crater Paschen S lies across the southwestern rim of Paschen. As a result, most of the southern rim of Paschen is now gone. The remainder of the rim is not in much better condition. It is worn and eroded, with multiple small craterlets along the edge and inner wall. Most of the rim structure has been worn away by subsequent impacts and deposits of ejecta, and now forms a rounded dip into the curving interior. A small chain of craters cuts across the ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paschen-Back Effect
The Zeeman effect (; ) is the effect of splitting of a spectral line into several components in the presence of a static magnetic field. It is named after the Dutch physicist Pieter Zeeman, who discovered it in 1896 and received a Nobel prize for this discovery. It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field. Also similar to the Stark effect, transitions between different components have, in general, different intensities, with some being entirely forbidden (in the dipole approximation), as governed by the selection rules. Since the distance between the Zeeman sub-levels is a function of magnetic field strength, this effect can be used to measure magnetic field strength, e.g. that of the Sun and other stars or in laboratory plasmas. The Zeeman effect is very important in applications such as nuclear magnetic resonance spectroscopy, electron spin resonance spectroscopy, magnetic resonance i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Spectral Series
The emission spectrum of atomic hydrogen has been divided into a number of spectral series, with wavelengths given by the Rydberg formula. These observed spectral lines are due to the electron making transitions between two energy levels in an atom. The classification of the series by the Rydberg formula was important in the development of quantum mechanics. The spectral series are important in astronomical spectroscopy for detecting the presence of hydrogen and calculating red shifts. Physics A hydrogen atom consists of an electron orbiting its nucleus. The electromagnetic force between the electron and the nuclear proton leads to a set of quantum states for the electron, each with its own energy. These states were visualized by the Bohr model of the hydrogen atom as being distinct orbits around the nucleus. Each energy level, or electron shell, or orbit, is designated by an integer, as shown in the figure. The Bohr model was later replaced by quantum mechanics in which the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
