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Gamow [3] first solved the one-dimensional case of quantum tunneling using the WKB approximation.Considering a wave function of a particle of mass m, we take area 1 to be where a wave is emitted, area 2 the potential barrier which has height V and width l (at < <), and area 3 its other side, where the wave is arriving, partly transmitted and partly reflected.
The reaction rate density between species A and B, having number densities n A,B, is given by: = where k is the reaction rate constant of each single elementary binary reaction composing the nuclear fusion process: = here, σ(v) is the cross-section at relative velocity v, and averaging is performed over all velocities.
[18] [19] [20] This work, in turn, evolved from his fundamental discovery of quantum tunneling as the mechanism of nuclear alpha decay, and his application of this theory to the inverse process to calculate rates of thermonuclear reaction. At first, Gamow believed that all the elements might be produced in the very high temperature and density ...
The Sommerfeld parameter η, named after Arnold Sommerfeld, is a dimensionless quantity used in nuclear astrophysics in the calculation of reaction rates between two nuclei and also appears in the definition of the astrophysical S-factor. It is defined as [1]
The Gamow–Teller transition is a pseudovector transition, that is, the selection rules for beta decay caused by such a transition involve no parity change of the nuclear state. [2] The spin of the parent nucleus can either remain unchanged or change by ±1.
In physical cosmology, the Alpher–Bethe–Gamow paper, or αβγ paper, was created by Ralph Alpher, then a physics PhD student, his advisor George Gamow, and Hans Bethe. The work, which would become the subject of Alpher's PhD dissertation, argued that the Big Bang would create hydrogen , helium and heavier elements in the correct ...
The first detailed calculations of the primordial isotopic abundances came in 1966 [3] [4] and have been refined over the years using updated estimates of the input nuclear reaction rates. The first systematic Monte Carlo study of how nuclear reaction rate uncertainties impact isotope predictions, over the relevant temperature range, was ...
In nuclear physics, the astrophysical S-factor S(E) is a rescaling of a nuclear reaction's total cross section σ(E) to account for the Coulomb repulsion between the charged reactants. It determines the rates of nuclear fusion reactions that occur in the cores of stars .