Total Born cross section of $e^+e^-$-pair production in relativistic ion   collisions from differential equations
  We apply the differential equation method to the calculation of the total Born cross section of the process $Z_1Z_2\to Z_1Z_2e^+e^-$. We obtain explicit expression for the cross section exact in the relative velocity of the nuclei. 
Roman N. Lee and Kirill T. Mingulov
hep-ph nucl-th physics.atom-ph