Classical analysis of antihydrogen recombination in a strong magnetic field

The influence ofthe strong magnetic field on the spontaneous recombination ofthe antihydrogen in cold positron-antiproton plasma is studied. The consideration is based on the analysis of the classical trajectories. The calculation of the relative cross section ofthe positron capture is carried out using the Monte-Carlo method and then the result is compared with the one in the situation when the magnetic field is absent. It is expected that since the trajectory of the positron in the magnetic and Coulomb fields is rather complicated, and the free positron passes the nucleus many times, the probability of the radiative capture will be greater than in the zero magnetic field, when the positron having the positive energy passes the nucleus only once. However, our calculations showed that the magnetic field does not affect significantly the radiative recombination rate within the approximations used. The comparison with the experimental study of the recombination of matched beams of electrons and filly ionized carbon nuclei in the magnetic field revealed fourfold underestimation of the relative recombination cross section, which is probably a manifestation ofessentially quantum effects.