Energetics and Potential Barriers

Although the reactions mentioned above are the most important ones for protons, deuterons, and a particles at present, other transformations are possible and are observed occasionally. Among these are (p,a), (p,d), ( , ), (d,H3), (a, n + p), and a, 3n + p) types. Inelastic scattering—that is, (p,p), (d,d)y and (a,a) reactions (in which a particle hits the target and the same type of particle is ejected from the target with less energy)— have been also observed but are not common. 

Nuclear reaction energies may be included in nuclear equations, just as chemical reaction energies are included in thermochemical equations  

however, that thermonuclear equations refer to individual atoms whereas thermochemical equations generally refer to molar quantities. Just as chemical reactions may be exo- or endothermic, nuclear reactions are sometimes described as exoergic or endoergic 

If the masses of the reactants and products are known, the energy of the reaction is easily calculated by multiplying the loss (or gain) in mass by 931 (Mev per atomic mass units. Either the masses of the nuclei or the masses of the atoms themselves (which are generally more readily available) may be used for such calculations since generally the number of electrons does not change. 

It appears from the figure given that the (a,p) reaction on N14 requires 

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