Linear energy transfer particle

Linear Energy Transfer (LET)—A measure of the energy that a charged particle transfers to a material per unit path length. 

The range in tissues and linear energy transfer (LET) depend on the type of radiation emitted and its energy. The potent lethality of Auger and low-energy conversion electrons is demonstrated by intranuclear localization of the radioisotope due to their short ranges (about one cell nucleus in diameter). Alpha particles have ranges of several cell diameters (40-90 pm) and are effective in... 

Linear energy transfer (LET) A function of the capacity of the radiation to produce ionization. LET is the rate at which charged particles transfer their energies to the atoms in a medium and a function of the energy and velocity of the charged particle. See Radiation dose. 

Because of the high linear energy transfer (LET) of the particles produced by the 10B(n,a)7Li reaction, the production of secondary ions is not enhanced in the presence of oxygen with low-LET radiation such as external photon irradiation, tissues... 

Radiation quality is defined by the nature, charge, and energy spectrum of the particles and can be characterized by the linear energy transfer (LET) or, alternatively, by the micro-dosimetric spectra at the point of interest under the actual irradiation conditions. 

The stopping power of a material for a particular radiation is commonly expressed as the rate of energy loss (R.E.L.) or the linear energy transfer (L.E.T.) of the radiation in the material. These quantities are assumed to be proportional to the linear ion density and the specific ionization. Stopping powers range from approximately 106 e.v./cm. for fast electrons (1 Mev.) in water to 1011 e.v./cm. for fission recoils. The ranges of particles are frequently expressed in mg./cm.2, which when multiplied by the density of the material yields the range. 

One of the characteristics of radiation considered in radiation chemistry and in radiobiology is the linear energy transfer (LET). For fast charged particles the LET practically equals the ionization losses (or polarization losses, in condensed media) and is given by the formulas for the stopping power presented in Section V.A. 

The rate of energy loss from the particle per unit length of track, or Linear Energy Transfer (LET), was known to follow the Bragg curve with a maximum LET close to the end of the particle s track. Be the (1933(8)) derived theoretical expression for this quantity for electrons and other charged particles. For electrons this has the form ... 

An alpha particle is heavily charged with a mass equal to 7,300 times that of an electron. Yet energy can be transferred to particles going only twice as fast as the alpha particle. Since it requires 33.85 eV to produce an electron pair, a 5 MeV can produce 7,400 pairs within 1 micron (micrometer) of the decay. One micron (1/1,000,000 meters 1/1,000 millimeters 15% of the diameter of a human red blood cell) is much thinner than a sheet of paper. This linear energy transfer (LET) is said to be much greater than is... 

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