The generation and acceleration of low-emittance flat beams for future linear colliders

Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of {dollar}gammaepsilonsb{lcub}x{rcub}=3times 10sp{lcub}-6{rcub}{dollar} m-rad and {dollar}gammaepsilonsb{lcub}y{rcub}=3times 10sp{lcub}-8{rcub}{dollar} m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also low intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate "fundamental" limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future.