Thresholds of ultraperipheral processes

Abstract

Threshold behavior of the cross sections of ultraperipheral nuclear interactions is studied. Production of $e^{+}{e}^{-}$ and ${\mu }^{+}{\mu }^{-}$ pairs as well as ${\pi }^0$ and parapositronium is treated. The values of corresponding energy thresholds are presented and the total cross sections of these processes at the newly constructed NICA and FAIR facilities are estimated.

Comments: 8 pg