Collisional de-excitation of rare-gas metastable atoms Ar, Kr, Xe by molecular hydrogen and deuterium

Absolute cross sections for the collisional de-excitation of the metastable rare-gas atoms Ar ( 3 P 0.f2 ), Kr ( 3 P 0.2 ) and Xe ( 3 P 0.2 ) by molecular hydrogen and deuterium have been measured. The experiment employs a velocity-selected metastable atom beam and a collision chamber with a variable length. During a collision, transfer of electronic energy from the metastable atom ideas to dissociation of the target molecule. In the case of argon metastable atoms this process may be complicated by other de-excitation mechanisms.