RELATIVISTIC ANTIHYDROGEN PRODUCTION

Antihydrogen has recently been produced in collisions of antiprotons w ith ions. While passing through the Coulomb field of a nucleus an anti proton will create an electron-positron pair. In rare cases the positr on is bound by the antiproton and an antihydrogen atom produced. We ca lculate the production of relativistic antihydrogen atoms by bound-fre e pair production. The cross section is calculated in the semiclassica l approximation (SCA), or equivalently in the plane wave Born approxim ation (PWBA) using exact Dirac-Coulomb wave functions. We compare our calculations to the equivalent photon approximation (EPA).