COLLISIONAL QUENCHING OF H(3L) ATOMS BY MOLECULAR HYDROGEN

The de-excitation cross sections of H atoms colliding with molecular hydrogen were determined in the velocity range of 2-. At a mean velocity of the de-excitation cross sections are , and . The velocity dependence of the de-excitation cross sections observed in the experiment agrees with the quadrupole-H dipole interaction and with the quantum character of the molecular rotation.