Abstract
We perform a double-species magneto-optical trap of 87Rb and 39K. The experiment apparatus of lasers, vacuum system, MOT and imaging system is described. Typically the atom numbers are 1×108 for 87Rb and 1×109 for 39K in double MOT operation. Cross-species cold collision loss was observed. The heteronuclear cold collision loss rate is determined by loading one species MOT with the presence and absence of the other species MOT. The cross-species MOT is a suitable source to form the cold mixture.