decay constant


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de·cay con·stant

the fractional change in the number of atoms of a radionuclide that occurs in unit time; the constant λ in the equation for the fraction (dN/N) of the number of atoms (N) of a radionuclide disintegrating in time dt, dN/N = -λdt.

de·cay con·stant

(dĕ-kā' kon'stănt)
The fractional change in the number of atoms of a radionuclide that occurs in a unit of time; the constant l in the equation for the fraction (DN/N) of the number of atoms (N) of a radionuclide disintegrating in time Dt, DN/N = - lDt.
Synonym(s): radioactive constant.
References in periodicals archive ?
where dN/dt is the rate of decay of a radioactive isotope, N is the present amount of a radioactive isotope (called the parent) in a sample, [N.sub.0] is the amount of parent isotope in the sample at the time of its formation, t is the age of the sample, and [lambda] is the decay constant of the parent isotope.
In addition, the decay properties such as decay constants, leptonic decay width, and the branching ratio of HLM are calculated.
The meson masses and decay constants needed in our calculations are taken as (in units of Mev) 3]
In order to estimate the error of the calculated parameters, variations of the Borel parameter, continuum thresholds, and leptonic decay constants, as the most significant reasons of the uncertainties, are considered.
The increased decay constants resulted from the reduction in slow moving L(0,1) and L(0,3) modes.
where I, [I.sub.0], and t are as defined in (1), [[alpha].sub.i] are time-invariant constants, and [[tau].sub.i] are the decay constants (also called decay times) of the exponential components.
chinensis 5.46 P < 0.001 3.51 P < 0.001 1.70 P < 0.054 TABLE 2: Average decay constant and half-life ([t.sub.50]) of leaf litter of selected cropland agroforest horticultural tree species during microbial decomposition in dry and wet season.
where [SER.sub.a](t) = calculated area emission rate at time t([micro]g [m.sup.-2] [h.sup.-1]), [SER.sub.a,0]= initial emission rate ([micro]g [m.sup.-2] [h.sup.-1]), andk= first order decay constant (h).
a = decay constant, which is unique for each radioactive isotope
RUSLE computes decomposition of organic matter in the ground cover and the soil biomass pools; the rate of decomposition is mainly governed by a user-defined decay constant, and adjusted according to monthly temperature and precipitation.
The consistency of dating results worldwide, especially the use of different decay schemes or the use of more than one decay constant on the same rock, confirms the accuracy and reliability of age-dating technique.
When the wickets are down the asymptotic remain-ing score is lower and the exponential decay constant is higher and we have: