Simple loss scaling laws for quadrupoles and higher-order multipoles used in antihydrogen traps
Simple scaling laws strongly suggest that for antihydrogen relevant parameters, quadrupole magnetic fields will transport particles into, or near to, the trap walls. Consequently quadrupoles are a poor choice for antihydrogen trapping. Higher order multipoles lead to much less transport.
J. Fajans, W. Bertsche, K. Burke, A. Deutsch, S. F. Chapman, K. Gomberoff, D. P. van der Werf, and J. S. Wurtele, in NON-NEUTRAL PLASMA PHYSICS VI: Workshop on Non-Neutral Plasmas 2006 (American Institute of Physics, New York, 2006), AIP vol. 862, p. 176 (2006)