Collisions of Magnetically Trapped Cold Methyl Radicals with Atoms

Manish Vashishta, Jiahong Hu, Pavle Djuricanin, Tony Mittertreiner, Takamasa Momose

Department of Chemistry, University of British Columbia, Vancouver, Canada 

Cold atomic collisions have been characterized by known interatomic potentials, and various quantum effects such as resonance scattering have been explained by the standard scattering theories. On the other hand, collisions of cold molecules, especially those of reactive molecules, have been studied less than those of atoms due to the difficulties in making cold molecules, and information is still lacking to fully understand cold collisional processes of molecules with complex internal structures.

Recently, we demonstrated that methyl radicals, one of the fundamental and important reactive intermediates, can be trapped in a magnetic trap below 200 mK [1]. In this work, we report on measurements of trap-loss due to collisions between the trapped cold methyl radicals and ensembles of room temperature Helium and Argon atoms. The observed trap-loss rates are compared with the loss rate obtained from theoretical calculations. Our latest results which include observation of quantum diffractive collisions and determination of C₆ coefficient between the colliding partners will be discussed.