Collision between magnetically trappedNHmolecules in the(N=0,J=1)state

Abstract

Elastic and inelastic collisions between $\mathrm{NH}$ molecules in the $(N=0,J=1)$ state were analyzed. These analyses showed that the elastic collision is caused mainly by electric dipole-induced dipole interaction, and the inelastic collision is caused mainly by the magnetic dipole-dipole interaction. The collision cross sections obtained by the quantum and classical methods are roughly in good agreement in the kinetic-energy region of $5--500\phantom{\rule{0.3em}{0ex}}\mathrm{mK}$. Moreover, the ratio of the inelastic-collision rate to the elastic-collision rate is lower than 1/200. These results show that the $\mathrm{NH}$ molecule is advantageous to perform evaporative cooling.