The equations may also need modifications to account for pair production of electron-positron pairs ( or other particles at the highest temperatures ).
32.
For the most frequent jet pair production process, the two particle scattering, the jet production cross section in a hadronic collision is given by
33.
For gamma rays ( uncharged ), their energy is converted to an energetic electron via either the photoelectric effect, Compton scattering or pair production.
34.
The reverse process, pair production, is the dominant mechanism by which high-energy photons such as gamma rays lose energy while passing through matter.
35.
The probability of pair production in photon-matter interactions increases with photon energy and also increases approximately as the square of atomic number of the nearby atom.
36.
At the high densities of a stellar core, pair production and annihilation occur rapidly, thereby keeping gamma rays, electrons, and positrons in thermal equilibrium.
37.
:: Any charged primary above a few MeV is likely to interact in the atmosphere via pair production, which is the essential mechanism for a shower.
38.
Stars above will have enough mass to create pairs of electrons and positrons; in these stars there will be greater pair production than in stars less than.
39.
The exact analytic form for the cross section of pair production must be calculated through quantum electrodynamics in the form of Feynman diagrams and results in a complicated function.
40.
In a pair-instability supernova, the pair production effect causes a sudden pressure drop in the star's core, leading to a rapid partial collapse.
