Heteronuclear collisions between laser-cooled metastable neon atoms

We investigate heteronuclear collisions in isotope mixtures of laser-cooled metastable (P-3(2)) neon. Experiments are performed with spin-polarized atoms in a magnetic trap for all two-isotope combinations of the stable neon isotopes Ne-20, Ne-21, and Ne-22. We determine the rate coefficients for heteronuclear ionizing collisions to beta(21,20) = (3.9 +/- 2.7) x 10(-11) cm(3)/s, beta(22,20) = (2.6 +/- 0.7) x 10(-11) cm(3)/s, and beta(21,22) = (3.9 +/- 1.9) x 10(-11) cm(3)/s. We also study heteronuclear elastic collision processes and give upper bounds for heteronuclear thermal relaxation cross sections. This work significantly extends the limited available experimental data on heteronuclear ionizing collisions for laser-cooled atoms involving one or more rare gas atoms in a metastable state.