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The following apply for the nuclear reaction: a + b ↔ R → c. in the centre of mass frame, where a and b are the initial species about to collide, c is the final species, and R is the resonant state.
Nuclear reactions may be shown in a form similar to chemical equations, for which invariant mass must balance for each side of the equation, and in which transformations of particles must follow certain conservation laws, such as conservation of charge and baryon number (total atomic mass number). An example of this notation follows:
Nuclear scientists and engineers often need to know where neutrons are in an apparatus, in what direction they are going, and how quickly they are moving. It is commonly used to determine the behavior of nuclear reactor cores and experimental or industrial neutron beams. Neutron transport is a type of radiative transport.
In nuclear physics and chemistry, the Q value for a nuclear reaction is the amount of energy absorbed or released during the reaction. The value relates to the enthalpy of a chemical reaction or the energy of radioactive decay products. It can be determined from the masses of reactants and products. Q values affect reaction rates.
In complex reactions, stoichiometries are often represented in a more compact form called the stoichiometry matrix. The stoichiometry matrix is denoted by the symbol N. [10] [11] [12] If a reaction network has n reactions and m participating molecular species, then the stoichiometry matrix will have correspondingly m rows and n columns.
The multiplication factor, k, is defined as (see nuclear chain reaction): k = number of neutrons in one generation / number of neutrons in preceding generation . If k is greater than 1, the chain reaction is supercritical, and the neutron population will grow exponentially.
In the 1 H(15 N,αγ) 12 C reaction (or indeed the 15 N(p,αγ) 12 C inverse reaction), the energetic emitted γ ray is characteristic of the reaction and the number that are detected at any incident energy is proportional to the hydrogen concentration at the respective depth in the sample. Due to the narrow peak in the reaction cross section ...
Strictly speaking the above equation holds also for systems with chemical reactions if the terms in the balance equation are taken to refer to total mass, i.e. the sum of all the chemical species of the system. In the absence of a chemical reaction the amount of any chemical species flowing in and out will be the same; this gives rise to an ...