The rf particle separator, proposed in 1959 by W.K.H. Panofsky and now in preparation for the Brookhaven Alternating Gradient Synchrotron, required a rf structure which gives a transverse impulse to a passing relativistic particle. In order to produce an accumulative transverse deflection of a traveling charged particle with an electromagnetic field, it is necessary that the field contains a synchronous component and in principle, waveguides and cavities are equivalent with respect to the particle dynamics. It was pointed out by H.G. Hereward, that the electric and magnetic deflection of a transverse electric mode (i.e., with no electric field component parallel to the direction of the particle velocity) cancel exactly at all particle velocities. The deflecting force of a transverse magnetic mode on a synchronous particle with the velocity v is proportional to the factor 1-(v/c)2 and vanishes therefore in the case of relativistic particles.

Abstract: "Production of [rho]'s and [omega]'s in [pi]- + p and p + [letter p with a bar over it] interactions is discussed. The [rho] is presumably a J = 1-, 1 = 1 state and thus can decay into 2[pi]'s via a strong coupling. The [omega] is probably J = 1-, 1 = 0 which can also decay into 2[pi]'s via electromagnetic coupling. A theoretical description of this situation is presented in terms of coupled time-dependent Schroedinger equations which mix [rho] and [omega] states that are assumed to be isotopically pure at the time of production. The interference between the two resonances was found to have the effect of extending the 2[pi] spectrum toward the [omega] mass."