Enhancement of low-mass dileptons in ultraperipheral collisions

TL;DR

This paper demonstrates that low-mass dilepton production in ultraperipheral collisions is significantly enhanced by Coulomb effects, with potential implications for collider experiments and astrophysics.

Contribution

It introduces the role of the Sommerfeld-Gamow-Sakharov factor in enhancing low-mass dilepton production in ultraperipheral collisions, highlighting observable effects at NICA and LHC.

Findings

Enhanced low-mass dilepton production due to SGS factor

Potential detection of increased 511 keV photons

Implications for astrophysical phenomena

Abstract

It is shown that production of low-mass $e^+e^-$-pairs in ultraperipheral nuclear collisions is enhanced due to the Sommerfeld-Gamow-Sakharov (SGS) factor. This effect is especially strong near the threshold of creation of unbound $e^+e^-$-pairs with low masses in the two-photon fusion. Coulomb attraction of the non-relativistic components of such pairs may lead to the increased intensity of 511 keV photons. It can be recorded at the NICA collider and has some astrophysical implications. The analogous effect can be observed at LHC in dilepton production.