Photon-nucleus pair production can only occur if the photons have an energy exceeding twice the rest energy (mec2) of an electron (1.022 MeV), photon-photon pair production may occur at 511 KeV; the same conservation laws apply for the generation of other higher energy leptons such as the muon and tauon (for two photons each should have the one-particle energy in the center of momentum frame, for one photon and a heavy nucleus, the photon needs the entire pair rest energy). These interactions were first observed in Patrick Blackett's counter-controlled cloud chamber, leading to the 1948 Nobel Prize in Physics.
In semiclassical general relativity, pair production is also invoked to explain the Hawking radiation effect. According to quantum mechanics, at short scales short-lived particle-pairs are constantly appearing and disappearing (see quantum foam); in a region of strong gravitational tidal forces, the two particles in a pair may sometimes be wrenched apart before they have a chance to mutually annihilate. When this happens in the region around a black hole, one particle may escape, with its antiparticle being captured by the hole.
Pair production is also the hypothesized mechanism behind the Pair instability supernova type of stellar explosions, where pair production suddenly lowers pressure inside a supergiant star, leading to a partial implosion, and then explosive thermonuclear burning. Supernova SN 2006gy is hypothesized to have been a pair production type supernova.
In 2008 the Titan laser aimed at a 1-millimeter-thick gold target was used to generate positron electron pairs in large numbers.
Wednesday, July 28, 2010
pair production of electron

Pair production refers to the creation of an elementary particle and its antiparticle, usually from a photon (or another neutral boson). This is allowed, provided there is enough energy available to create the pair – at least the total rest mass energy of the two particles – and that the situation allows both energy and momentum to be conserved (though not necessarily on shell). All other conserved quantum numbers (angular momentum, electric charge) of the produced particles must sum to zero — thus the created particles shall have opposite values of each (for instance, if one particle has strangeness +1 then another one must have strangeness
Production of electron

physics is mostly related with physis so that study of electron is physics study. and electron are produce as; Process of two pion production in electron - polarized proton scattering is investigated. In Weizs\"acker-Williams approximation the differential spectral distributions and the spin-momentum correlations are considered. The spin correlation effects caused by $\rho$-meson widths are estimated to be of order of several percents. Both channels of $\pi^+\pi^-$ and $\pi^+\pi^0$ creation are considered. The effects of intermediate excited baryons are not considered. The spectral distributions on pion energy fractions in polarized and unpolarized cases are presented analytically and numerically.
Electron physics
Electrons are charged particles, and have a charge/mass ratio 2000 times greater than a proton. Electrons obey wave/particle duality principles. Electrons may be manipulated by both electrostatic and magnetic fields. Within the gun column electrons are accelerated to very high velocities and relativistic correction factors are required for accurate computation.
An electron moving at charge 'e' with a velocity 'v' in the presence of both an electric field 'E' and a magnetic field 'B' experiences both an electric and magnetic force.
The total force acting on the electron is F = e E + ev x B
Typical electron beam welding and processing systems utilise electrostatic forces for beam generation, and magnetic forces for beam manipulation and focusing.
An electron moving at charge 'e' with a velocity 'v' in the presence of both an electric field 'E' and a magnetic field 'B' experiences both an electric and magnetic force.
The total force acting on the electron is F = e E + ev x B
Typical electron beam welding and processing systems utilise electrostatic forces for beam generation, and magnetic forces for beam manipulation and focusing.
PhysicsQuest
Monday, July 26, 2010
BIOGRAPHY OF NEWTON


Isaac Newton was born on 4 January 1643 [OS: 25 December 1642][1] at Woolsthorpe Manor in Woolsthorpe-by-Colsterworth, a hamlet in the county of Lincolnshire. At the time of Newton's birth, England had not adopted the Gregorian calendar and therefore his date of birth was recorded as Christmas Day, 25 December 1642. Newton was born three months after the death of his father, a prosperous farmer also named Isaac Newton. Born prematurely, he was a small child; his mother Hannah Ayscough reportedly said that he could have fit inside a quart mug (≈ 1.1 litres). When Newton was three, his mother remarried and went to live with her new husband, the Reverend Barnabus Smith, leaving her son in the care of his maternal grandmother, Margery Ayscough. The young Isaac disliked his stepfather and held some enmity towards his mother for marrying him, as revealed by this entry in a list of sins committed up to the age of 19: "Threatening my father and mother Smith to burn them and the house over them."[10] While Newton was once engaged in his late teens to a Miss Storey, he never married and is believed to have been asexual, being highly engrossed in his studies and work.[11][12][13]
Newton in a 1702 portrait by Godfrey Kneller
Isaac Newton (Bolton, Sarah K. Famous Men of Science. NY: Thomas Y. Crowell & Co., 1889)From the age of about twelve until he was seventeen, Newton was educated at The King's School, Grantham (where his signature can still be seen upon a library window sill). He was removed from school, and by October 1659, he was to be found at Woolsthorpe-by-Colsterworth, where his mother, widowed by now for a second time, attempted to make a farmer of him. He hated farming.[14] Henry Stokes, master at the King's School, persuaded his mother to send him back to school so that he might complete his education. Motivated partly by a desire for revenge against a schoolyard bully, he became the top-ranked student.[15]
In June 1661, he was admitted to Trinity College, Cambridge as a sizar — a sort of work-study role.[16] At that time, the college's teachings were based on those of Aristotle, but Newton preferred to read the more advanced ideas of modern philosophers, such as Descartes, and of astronomers such as Copernicus, Galileo, and Kepler. In 1665, he discovered the generalised binomial theorem and began to develop a mathematical theory that would later become infinitesimal calculus. Soon after Newton had obtained his degree in August 1665, the university temporarily closed as a precaution against the Great Plague. Although he had been undistinguished as a Cambridge student,[17] Newton's private studies at his home in Woolsthorpe over the subsequent two years saw the development of his theories on calculus, optics and the law of gravitation. In 1667, he returned to Cambridge as a fellow of Trinity
Earthquakes and volcanic activ

The first hints that the LHC is seriously damaging life on Earth will come from an increase on earthquake and volcano activity. This is due to the fact that the LHC is creating a powerful gravito-magnetic field, a ‘ring’ of charged, massive particles that can interact with the magnetic fields of the magma and Earth’s center.
Disturbances on the Earth’s magnetic field by the magnets of the LHC and specially the charged positive c-speed flow of protons can come through 3 different processes:
- The possibility that the 27 kilometers continuous ring of charged protons can interact with self-similar charged flows in the magma or earth’s center, creating a powerful electro-magnetic effect, displacing magma and causing earthquakes and volcano activity. It is a fact that the first day that the charged, proton ring was created in 2008 it caused 4 significant Earthquakes, the first one in Iran, seconds after it was powered up.
The proton, charged ring could act as a new pole of a magnetic field with Earth’s inner fields.
- The creation of strange liquid, already produced in the first experiments, (Kaons at the LHC, hyperons at RHIC) could also provoke explosions in the magma. If stable, it will leak in increasing quantities to the center of the Earth. Some of it will remain in the center, forming the seed of a strangelet. Some will accrete and/or explode in the mantle, in highly energetic, tiny bombs.
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