Attenuation Coefficient


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attenuation coefficient

[ə‚ten·yə′wā·shən ‚kō·ə′fish·ənt]
(electromagnetism)
The space rate of attenuation of any transmitted electromagnetic radiation.

Attenuation Coefficient

 

(or extinction coefficient), a quantity inverse to the distance at which the radiation flux forming a parallel beam is attenuated as a result of the joint action of the absorption and scattering of light in a medium by a specified factor. When the factor is 10, the coefficient is called the decimal attenuation coefficient, and when the factor is e, it is called the natural attenuation coefficient. The attenuation coefficient is the sum of the absorption coefficient and the scattering coefficient of the medium. These coefficients depend on the set of frequencies v, or wavelengths λ, that characterize the initial flux. The value of the attenuation coefficient for the limiting case of a single frequency v is called the monochromatic attenuation coefficient. Like the absorption and scattering coefficients, the attenuation coefficient can be divided by the volume of the medium or by the mass of the attenuating substance; we shall call these two ratios the volume and mass attenuation coefficients, respectively.

References in periodicals archive ?
From the statistic of the linear regression, the attenuation coefficient is [[alpha].
Therefore attenuation coefficient, received optical power, SNR, and BER using (850nm) laser beam was studying in this Simulations work for above three systems shows in Figures (3,4,5).
The technique to calculate depth-invariant index involves three main steps: (1) generate a linear relationship between depth and radiance; (2) calculate the ratio of attenuation coefficients of band pairs; and, (3) calculate the depth-invariant index of bottom type (Figure 2).
We group all the numerical examples by the attenuation coefficient [alpha], and the computational results are presented in Table 2.
Table-3: Values of daily intake, correlation and attenuation coefficient of macro-micro nutrients detected by FFQ and 24HRs.
The study reached the following major conclusions: (1) This paper defined a temperature attenuation coefficient, a, which is an important parameter for the solutions of the coupled problem, because the temperature profile of smoke is shown to be exponential functions of a.
where S(E) is the photon spectrum (unnormalized fluence spectrum), [mu](E) is the photon attenuation coefficient for air for a photon of energy E, [d.
Some of the standardized values of ultrasonic velocity ([nu]) and attenuation coefficient ([alpha]) of few International standard samples are:
The attenuation coefficient, [alpha], is obtained from the best-fit equation.
The attenuation coefficient is made up of four parts can be expressed as the following: