electron-volt


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Related to electron-volt: kiloelectron volt

electron-volt,

abbr. eV, unit of energy used in atomic and nuclear physics; 1 electron-volt is the energy transferred in moving a unit chargecharge,
property of matter that gives rise to all electrical phenomena (see electricity). The basic unit of charge, usually denoted by e, is that on the proton or the electron; that on the proton is designated as positive (+e
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, positive or negative and equal to that charge on the electron, through a potentialpotential, electric,
work per unit of electric charge expended in moving a charged body from a reference point to any given point in an electric field (see electrostatics).
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 difference of 1 volt. The maximum energy of a particle acceleratorparticle accelerator,
apparatus used in nuclear physics to produce beams of energetic charged particles and to direct them against various targets. Such machines, popularly called atom smashers, are needed to observe objects as small as the atomic nucleus in studies of its
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 is usually expressed in multiples of the electron-volt, such as million electron-volts (MeV) or billion electron-volts (GeV). Because mass is a form of energy (see relativityrelativity,
physical theory, introduced by Albert Einstein, that discards the concept of absolute motion and instead treats only relative motion between two systems or frames of reference.
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), the masses of elementary particleselementary particles,
the most basic physical constituents of the universe. Basic Constituents of Matter

Molecules are built up from the atom, which is the basic unit of any chemical element. The atom in turn is made from the proton, neutron, and electron.
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 are sometimes expressed in electron-volts; e.g., the mass of the electron, the lightest particle with measurable rest mass, is 0.51 MeV/c2, where c is the speed of light.
References in periodicals archive ?
The INTEGRAL survey is the first of its kind to glimpse into the largely unexplored higher-energy, or "hard," X-ray regime of 20,000 to 40,000 electron-volts.
Iron also emits X rays at the slightly lower energy of 6,400 electron-volts.
For decades, astronomers have pondered how cosmic rays acquire their enormous energies, which can exceed 1,000 trillion electron-volts, far outstripping the energy produced by any particle accelerator on Earth.
The researchers found that they could increase the energy of injected electrons from 2 million to 30 million electron-volts over a distance of about 1 centimeter.
The results reveal a "dramatic transition" from one type of cosmic ray to another at an energy between 1018 and 1019 electron-volts, Eugene C.
6 billion electron-volts produced copious quantities of subatomic particles called upsilons.
But the bulk of the X-ray background - the high-energy spectrum above a few thousand electron-volts (eV) - remained a mystery.
Generated by data from the Compton Gamma Ray Observatory's (GRO) EGRET telescope, the map depicts emissions with an energy greater than 100 million electron-volts.

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