|
Sylvain Liberman
Sylvain Liberman (1934 – 5 August 1988) was a French physicist, specializing in atomic physics and laser spectroscopy. He is known as the leader of the scientific team that made the first measurements of the optical spectrum of francium.p. 101 (Page 100 consists of an advertisement.) Education and career Sylvain Liberman received his doctorate in 1971 from 's (Paris XI), which in 2020 was replaced by |
French People
The French people (french: Français) are an ethnic group and nation primarily located in Western Europe that share a common French culture, history, and language, identified with the country of France. The French people, especially the native speakers of langues d'oïl from northern and central France, are primarily the descendants of Gauls (including the Belgae) and Romans (or Gallo-Romans, western European Celtic and Italic peoples), as well as Germanic peoples such as the Franks, the Visigoths, the Suebi and the Burgundians who settled in Gaul from east of the Rhine after the fall of the Roman Empire, as well as various later waves of lower-level irregular migration that have continued to the present day. The Norse also settled in Normandy in the 10th century and contributed significantly to the ancestry of the Normans. Furthermore, regional ethnic minorities also exist within France that have distinct lineages, languages and cultures such as Bretons in Brittany, Occi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rydberg State
The Rydberg states of an atom or molecule are electronically excited states with energies that follow the Rydberg formula as they converge on an ionic state with an ionization energy. Although the Rydberg formula was developed to describe atomic energy levels, it has been used to describe many other systems that have electronic structure roughly similar to atomic hydrogen. In general, at sufficiently high principal quantum numbers, an excited electron-ionic core system will have the general character of a hydrogenic system and the energy levels will follow the Rydberg formula. Rydberg states have energies converging on the energy of the ion. The ionization energy threshold is the energy required to completely liberate an electron from the ionic core of an atom or molecule. In practice, a Rydberg wave packet is created by a laser pulse on a hydrogenic atom and thus populates a superposition of Rydberg states. Modern investigations using pump-probe experiments show molecular pathways ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paris-Saclay University Alumni
Paris-Saclay is a research-intensive and business cluster currently under construction in the south of Paris, France. It encompasses research facilities, two French major universities with higher education institutions (''grandes écoles'') and also research centers of private companies. In 2013, the Technology Review put Paris-Saclay in the top 8 world research clusters. In 2014, it comprised almost 15% of French scientific research capacity. The earliest settlements are from the 1950s, and this area was subsequently extended several times during the 1970s and 2000s. Several projects are underway to continue the development of the campus, including the relocation of some facilities. The area is now home to many of the Europe's largest high-tech corporations, and to the two French universities Paris-Saclay University (CentraleSupélec, ENS Paris-Saclay, Paris-Saclay Faculty of Science, etc.) and the Polytechnic Institute of Paris (''École Polytechnique'', Telecom Paris, etc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectroscopists
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter waves and acoustic waves can also be considered forms of radiative energy, and recently gravitational waves have been associated with a spectral signature in the context of the Laser Interferometer Gravitational-Wave Observatory (LIGO) In simpler terms, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Historically, spectroscopy originated as the study of the wavelength dependence of the absorption by gas phase matter of visible light dispersed by a prism. Spectroscopy, primarily in the electromagnetic spectrum, is a fundamental exploratory tool in the fields of astronomy, chemistry, materials science, and physics, allowing the composition, physical structure and ele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Researchers
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word "laser" is an acronym for "light amplification by stimulated emission of radiation". The first laser was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow. A laser differs from other sources of light in that it emits light which is ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling applications such as laser cutting and lithography. Spatial coherence also allows a laser beam to stay narrow over great distances (collimation), enabling applications such as laser pointers and lidar (light detection and ranging). Lasers can also have high temporal coherence, which allows them to emit light with a very narrow spectrum. Alternatively, temporal coherence can be used to produce ultrashort pulses of light w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1988 Deaths
File:1988 Events Collage.png, From left, clockwise: The oil platform Piper Alpha explodes and collapses in the North Sea, killing 165 workers; The USS Vincennes (CG-49) mistakenly shoots down Iran Air Flight 655; Australia celebrates its Bicentennial on January 26; The 1988 Summer Olympics are held in Seoul, South Korea; Soviet troops begin their withdrawal from Afghanistan, which is completed the next year; The 1988 Armenian earthquake kills between 25,000-50,000 people; The 8888 Uprising in Myanmar, led by students, protests the Burma Socialist Programme Party; A bomb explodes on Pan Am Flight 103, causing the plane to crash down on the town of Lockerbie, Scotland- the event kills 270 people., 300x300px, thumb rect 0 0 200 200 Piper Alpha rect 200 0 400 200 Iran Air Flight 655 rect 400 0 600 200 Australian Bicentenary rect 0 200 300 400 Pan Am Flight 103 rect 300 200 600 400 1988 Summer Olympics rect 0 400 200 600 8888 Uprising rect 200 400 400 600 1988 Armenian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1934 Births
Events January–February * January 1 – The International Telecommunication Union, a specialist agency of the League of Nations, is established. * January 15 – The 8.0 Nepal–Bihar earthquake strikes Nepal and Bihar with a maximum Mercalli intensity of XI (''Extreme''), killing an estimated 6,000–10,700 people. * January 26 – A 10-year German–Polish declaration of non-aggression is signed by Nazi Germany and the Second Polish Republic. * January 30 ** In Nazi Germany, the political power of federal states such as Prussia is substantially abolished, by the "Law on the Reconstruction of the Reich" (''Gesetz über den Neuaufbau des Reiches''). ** Franklin D. Roosevelt, President of the United States, signs the Gold Reserve Act: all gold held in the Federal Reserve is to be surrendered to the United States Department of the Treasury; immediately following, the President raises the statutory gold price from US$20.67 per ounce to $35. * February 6 – F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Les Houches
Les Houches () is a commune in the Haute-Savoie department in the Auvergne-Rhône-Alpes region of Eastern France. In 2017, it had a population of 2,943. Overview Les Houches, located 6 kilometres from Chamonix, is a ski resort with a domain which extends from an altitude of 950 metres up to 1900 metres. Long descents through tree-lined slopes are combined with impressive views of the Mont Blanc massif and the Chamonix valley. Les Houches is twinned with the Russian villages of Sochi and Krasnaya-Polyana and was chosen by the International Olympic Committee to assist in the organization of the 2014 Winter Olympic Games. Les Houches is the starting- and finishing-point of the popular Tour du Mont Blanc, a 7- to 10-day walk around the base of the Mont-Blanc Massif which takes in France, Italy, and Switzerland. Les Houches has four railway stations (, , , and ) on the Saint-Gervais–Vallorcine railway and the section from Les Houches to Servos holds the world record gradient for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Three Physicists Prize
The Three Physicists Prize (french: Prix des trois physiciens) is a physics prize awarded by the École Normale Supérieure (ENS) in Paris and the Eugène Bloch Foundation. It is named in honour of the physicists Henri Abraham, Eugene Bloch and Georges Bruhat, who were successive directors of the physics laboratory at the ENS and all of whom were murdered in Nazi concentration camps between 1943 and 1945. The prize was established by Bloch's widow. Winners * 1951 Jean Cabannes * 1952 Maurice Bayen * 1953 Gustave Ribaud * 1954 Maurice Ponte * 1955 ''not awarded'' * 1956 Nevill Francis Mott * 1957 H. B. G. Casimir * 1958 J. Robert Oppenheimer * 1959 André Danjon * 1960 Gaston Dupouy * 1961 Max Morand * 1962 Jean Weigle * 1963 Louis Néel * 1964 André Lallemand * 1965 Alfred Kastler * 1966 Francis Perrin * 1967 Pierre Auger * 1968 Jean-François Denisse * 1969 Jean-Claude Pecker * 1970 Albert Kirrmann * 1971 Jean Coulomb * 1972 André Guinier * 1973 Pierre Grivet * 1974 Jean R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cesium
Caesium (IUPAC spelling) (or cesium in American English) is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of , which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium has physical and chemical properties similar to those of rubidium and potassium. It is pyrophoric and reacts with water even at . It is the least electronegative element, with a value of 0.79 on the Pauling scale. It has only one stable isotope, caesium-133. Caesium is mined mostly from pollucite. The element has 40 known isotopes, making it, along with barium and mercury, one of the elements with the most isotopes. Caesium-137, a fission product, is extracted from waste produced by nuclear reactors. The German chemist Robert Bunsen and physicist Gustav Kirchhoff discovered caesium in 1860 by the newly developed method of flame spectroscopy. The first small-scale applications for caesium were a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
