MER (Meer), Simon van der( Dutch physicist and engineer, Nobel Prize in Physics, 1984)
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Biography MER (Meer), Simon van der
Dutch physicist and engineer Simon van der Meer was born in The Hague. The third of four children, he was the only son of a schoolteacher Peter van der Measure and nee Yetske Groenefeld. Parents valued the learning and the price of the material of the victims gave the children a good education. M. studied at the local grammar school and passed the final exams in 1943, when Holland was occupied by the Germans during the Second World War. As the Germans closed the Dutch universities, M. two years he studied the humanities in high school. But his interest in physics and engineering have grown steadily. His favorite occupation was messing with electronics. In the house of van der mers with each passing day more and more of the various devices and appliances, constructed by him. After the war M. enrolled in the Technical College in Delft in the specialty 'control devices' and in 1952. finished with an engineering degree. In the same year, M. became a member of the Research Laboratory of the firm 'Phillips' in Eindhoven and took part in the creation of an electron microscope and high-voltage equipment. V1956 g. he went to work at the European Center for Nuclear Research - CERN, formed two years earlier, as a consortium of 13 European countries. At CERN M. first worked on the technical project of a particle accelerator - the proton synchrotron (PS). Expressed particular interest in problems of control particle beams, M. spent several years focusing on the invention of the pulsating device, which he called the neutrino horn. This device is intended to increase the intensity of the neutrino fluxes - elementary particles with no electrical charge and almost devoid of mass. Neutrinos are emitted along with other particles in such reactions as beta decay (emission of electrons) of radioactive nuclei. V1965 g. M. designed a small storage ring - a device that allows using electromagnetic fields to hold charged particles, causing them to circulate through the ring. It was used in experiments to measure the magnetic properties of the muon - a particle, similar to the electron, but much more severe, which was originally discovered in cosmic rays. Participation in this experiment allowed M. acquainted with the principles of accelerator design and features of the thinking of physicists working in the field of high-energy. From 1967 to 1976. M. responsible for food control magnets intersecting storage rings at CERN and superprotonic Synchrotron (SPS) at 400 billion. electron volts. Intersecting storage rings allow particles such as protons, circulating in opposite directions on two different rings. Where storage rings intersect, the collision of colliding beams. In 1976. M. ranked among the project participants, . proposed by Carlo Rubbia, . David Klein and Peter McIntyre essence of the project was to make ATP in the experimental setup to detect the hypothetical W-and Z-particles (bosons), . associated with the nuclear (strong) interaction, . Search these particles, scientists conducted over many years. Their detection would be crucial to the confirmation of quantum field theories. . Physicists distinguish four fundamental gravitational interaction (attraction between the masses, . it holds together the parts of the universe), . electromagnetic, . connecting the atomic electrons with the nucleus, . atoms with atoms in molecules and underlying all chemical processes, . weak interaction, . responsible for some types of radioactivity, . example the emission of beta radiation (electrons), . and strong interaction, . restraint in the nucleus of protons, . neutrons and other subatomic particles, . compensating the opposing forces, . such as the mutual repulsion of tightly packed protons, . According to quantum field theory, interaction takes place through the exchange of fundamental particles, or quanta of the field. The father of quantum theory, Max Planck discovered in 1900 that the energy emitted is not continuous and discrete chunks, or quanta. In 1905, Mr.. Albert Einstein confirmed the quantum theory, showing that light, the wave nature of which was regarded as generally accepted for centuries, can act as a stream of individual particles. Quantum of light, like the quantum of any electromagnetic radiation, called photons. The electromagnetic interaction is carried out through the exchange of photons. The photon energy is proportional to the frequency of radiation. At zero photon rest mass of light or moving, or does not exist. In 1935. Japanese physicist Hideki Yukawa hypothesized that the force bond can be carried in quanta having a rest mass, and compute its estimated value of about 200 electron masses. In 1947, Mr.. English physicist Cecil F. Powell Yukawa discovered the particle in place at high altitude above the Earth cosmic ray collisions with nuclei. Since similar, but more light particles were found somewhat earlier at low altitudes, the Yukawa particle was called pi-meson, or pion, and the lighter particles became known as the mu-meson, or muon. Pion plays the role of carrier of the strong interaction, carrying out the connection between the protons and neutrons, as well as between intranuclear particles of the same name (only protons or only neutrons). . The existence of four fundamental interactions are not satisfied physicists . There have been several attempts to create a theory that covers all four of interaction within a unified approach. In 1960, Mr.. American physicist Sheldon L. Glashow proposed electroweak theory unifying electromagnetic and weak interactions. Glashow theory required the existence of three particles of the class of bosons (named after the Indian physicist Bose Satendranata): positively charged W +-particles, negatively charged W - particles and the neutral Z0-particle. The particles should be the vector W of the weak interaction, and all three new particles and photons - the electroweak interaction. Seven years later, American physicist Steven Weinberg and Pakistani physicist Abdus Salam independently predicted, . that W-and Z-particles should be ten times heavier than any previously known elementary particles and have extremely short lifetimes (less than 10-18 seconds)., . Italian physicist Rubbia, who was working at CERN in 1960 . and is seeking to W-and Z-particles in the National Accelerator Laboratory behalf farm, located near Chicago, in 1979. succeeded in convincing the leadership to rebuild the CERN SPS for such studies. Estimated cost of the work amounted to 100 million. dollars. Since the mass of W-and Z-particles are large, to observe them will require an enormous amount of energy. The equivalence of mass and energy, deduced from Einstein's relativity theory, allows us to estimate the number of required energy. This estimate exceeded the capacity of existing particle accelerators, in particular, because the collisions of fast-moving particles are not all the energy expended on the formation of new particles. Rubbia and his colleagues suggested the use of ATP as a proton-antiproton collider - collider. Antiprotons - a particle of antimatter, similar to protons, ie. particle-doubles in all but the charge that they have negative. The existence of the first antiparticle - antielectron - predicted in 1928. Paul A. Maurice Dirac. It was discovered experimentally by Carl D. Anderson in 1932. and is called positron. The collision of a particle and antiparticle, they annihilate with a release of energy in the form of, for example, gamma. In the reworked on the proposed draft of ATP, protons and antiprotons as particles with opposite electric charges have been accessed in opposite directions at the same magnetic field inside the same ring. In the collision of particles as a result of annihilation of releases were to the amount of energy required for the birth of W-and Z-particles. . The project encountered many difficulties: problems with the accumulation of the required number of antiprotons in a sufficiently intense beam of (anti-matter particles are extremely rare) and the design of the detector, . allows to identify the particles and determine their characteristics, . Life of the particles themselves is too short so that they can be observed directly, but the products of their decomposition can provide valuable 'evidence' about what was happening all. One of the decay products must have been elusive neutrino experimenters, . unusual properties which, . including the lack of charge and mass, . almost completely exclude any interaction with matter, . necessary for the operation of any detector, . By the conclusion of the existence of neutrino physics come by summing the energy and momentum of other degradation products in all directions, and identifying the missing energy and momentum. Rubbia and more than a hundred other scientists have built a complex 1200-ton detector camera. Another group - the smaller, 200-ton detector to confirm the results obtained M. managed to solve the problem of supply of antiprotons with a special storage ring. For antiprotons fixed copper target bombarded bunches of protons accelerated to high energies at the old PS. Antiproton came in the form of bursts quick succession in a storage ring. Accumulated in the ring around for the day antiprotons injected in the PS pre-acceleration, and then came to the ATP, which then enters pre-accelerated proton group, also derived from the SAR. The protons and antiprotons to energies of finally dispersed about 300 billion. electron-volts of ATP turning into a giant storage ring with a diameter of 4 miles, in which particles and antiparticles, divided into three groups, circulating in opposite directions and collided 'head-' in six well-defined points. In two of these points were placed detectors. The key to creating successful current drive antiprotons was a realization of the proposed M. so-called stochastic cooling. We had to take each cluster of injected antiprotons, compress it into a tight narrow momentum and add to the increasingly large 'flock' of antiprotons, flying along the axial line evacuated to high vacuum chamber drive. Formed a cloud of antiprotons had to be stored so that it was not in the way of the flow of new clots. Complex control system included a number of pickup electrodes (electrodes, sensors), . who watched the shifting orbits of particles and sent strengthened appropriately located signals on the front of the electrodes, . that corrective 'shocks' have focused in a more subtle path of the beam, . when clot particles was in a points adjustment, . More aftershocks changed the speed of compressed bunches so that they will be reunited with the accumulated. Under cooling in this case refers to a decrease of particle velocities relative to each other. Stochasticity involves an accident, unavoidable in those cases where we have to deal with a large number of particles M. said later that 'the process of such complexity could not have overcome if not for the efforts and dedication of several hundred people. " . Collisions of protons and antiprotons, committing 50 000 revolutions per second around the ring with a circumference of more than 12.5 miles, allowed to reach a record at the time energy . Collider was put into operation in 1982, and the opening of W + and W - particles was announced in January 1983. A few months later followed by reports about the discovery of more elusive Z-particle. M. and Rubbia was awarded the Nobel Prize in Physics 1984. 'a decisive contribution to a large project, which led to the discovery of field particles W and Z, carriers of the weak interaction'. The experimental discovery of quanta of the weak interaction has been enthusiastically received throughout the world as one of the most important achievements in the physics of XX century. Opening of W-and Z-particles allowed to explain, . why the sun does not overheat and incinerates all life on Earth, . made more evidence the so-called theory of 'Big Bang' in cosmology, . to bring science to the possible realization of Einstein's Dreams, . though in a modified form of a unified field theory, . covering all four fundamental interactions in nature M, . continues to design and build at CERN storage rings ever more sophisticated designs. M. since 1966. married Catharina M. Koopman. They had a son and a daughter. He is an avid skier and a tourist, in his spare time likes to read fiction. M. elected an honorary doctorate by the University of Geneva, Amsterdam and Genoa, was awarded a medal and prize Daddella London Physics Institute (1982). He is a member of the Royal Netherlands Academy of Sciences and the American Academy of Arts and Sciences.
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