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This choice also places K-alpha firmly in the X-ray energy range. Similarly to Lyman-alpha, the K-alpha emission is composed of two spectral lines, K-alpha 1 (Kα 1) and K-alpha 2 (Kα 2). [6] The K-alpha 1 emission is slightly higher in energy (and, thus, has a lower wavelength) than the K-alpha 2 emission. For all elements, the ratio of the ...
A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus, known as beta decay. There are two forms of beta decay, β − decay and β + decay, which produce electrons and positrons, respectively.
Alpha particles, also called alpha rays or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to a helium-4 nucleus. [5] They are generally produced in the process of alpha decay but may also be produced in different ways. Alpha particles are named after the first letter in the Greek alphabet, α.
Beta radiation from linac accelerators is far more energetic and penetrating than natural beta radiation. It is sometimes used therapeutically in radiotherapy to treat superficial tumors. Beta-plus (β +) radiation is the emission of positrons, which are the antimatter form of electrons. When a positron slows to speeds similar to those of ...
The transitions are named sequentially by Greek letters: from n = 2 to n = 1 is called Lyman-alpha, 3 to 1 is Lyman-beta, 4 to 1 is Lyman-gamma, and so on. The series is named after its discoverer, Theodore Lyman. The greater the difference in the principal quantum numbers, the higher the energy of the electromagnetic emission.
The rays were given the names alpha, beta, and gamma, in increasing order of their ability to penetrate matter. Alpha decay is observed only in heavier elements of atomic number 52 and greater, with the exception of beryllium-8 (which decays to two alpha particles). The other two types of decay are observed in all the elements.
the beta coefficient, the non-diversifiable risk, of an asset in mathematical finance; the sideslip angle of an airplane; a beta particle (e − or e +) the beta brain wave in brain or cognitive sciences [9] ecliptic latitude in astronomy [10] the ratio of plasma pressure to magnetic pressure in plasma physics [11] β-reduction in lambda calculus
This value for α gives µ 0 = 4π × 0.999 999 999 87 (16) × 10 −7 H⋅m −1, 0.8 times the standard uncertainty away from its old defined value, with the mean differing from the old value by only 0.13 parts per billion. Historically the value of the reciprocal of the fine-structure constant is often given.