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The starting point for the derivation of the Bethe–Salpeter equation is the two-particle (or four point) Dyson equation = + in momentum space, where "G" is the two-particle Green function | | , "S" are the free propagators and "K" is an interaction kernel, which contains all possible interactions between the two particles.
Thus computing the gamma function becomes a matter of evaluating only a small number of elementary functions and multiplying by stored constants. The Lanczos approximation was popularized by Numerical Recipes , according to which computing the gamma function becomes "not much more difficult than other built-in functions that we take for granted ...
The decay scheme of a radioactive substance is a graphical presentation of all the transitions occurring in a decay, and of their relationships. Examples are shown below. It is useful to think of the decay scheme as placed in a coordinate system, where the vertical axis is energy, increasing from bottom to top, and the horizontal axis is the proton number, increasing from left to right.
Experimental investigations into the time-dependent relaxation behavior of viscoelastic materials are characterized by a very fast decrease of the stress at the beginning of the relaxation process and an extremely slow decay for large times. It can even take a long time before a constant asymptotic value is reached.
The incoming gamma ray effectively knocks one or more neutrons, protons, or an alpha particle out of the nucleus. [1] The reactions are called (γ,n), (γ,p), and (γ,α). Photodisintegration is endothermic (energy absorbing) for atomic nuclei lighter than iron and sometimes exothermic (energy releasing) for atomic nuclei heavier than iron.
The Nakagami distribution or the Nakagami-m distribution is a probability distribution related to the gamma distribution. The family of Nakagami distributions has two parameters: a shape parameter / and a scale parameter >. It is used to model physical phenomena such as those found in medical ultrasound imaging, communications engineering ...
Multipole radiation is a theoretical framework for the description of electromagnetic or gravitational radiation from time-dependent distributions of distant sources. These tools are applied to physical phenomena which occur at a variety of length scales - from gravitational waves due to galaxy collisions to gamma radiation resulting from nuclear decay.
The competition between IC and gamma decay is quantified in the form of the internal conversion coefficient which is defined as = / where is the rate of conversion electrons and is the rate of gamma-ray emission observed from a decaying nucleus.