With the advent of the SLAC electron-positron linear collider (SLC) in the 100 GeV center-of-mass energy range, research and development work on even higher energy machines of this type has started in several laboratories in the United States, Europe, the Soviet Union and Japan. These linear colliders appear to provide the only promising approach to studying {dollar}esp{lcub}+{rcub}esp{lcub}-{rcub}{dollar} physics at center-of-mass energies approaching 1 TeV.; This thesis concerns itself with the study of radio frequency properties of periodic accelerating structures for linear colliders and their interaction with bunched beams. The topics that have been investigated are: (1) Experimental measurements of the energy loss of single bunches to longitudinal modes in two types of structures, using an equivalent signal on a coaxial wire to simulate the beam. (2) A method of cancelling the energy spread created within a single bunch by longitudinal wakefields, through appropriate shaping of the longitudinal charge distribution of the bunch. (3) Derivation of the complete transient beam-loading equation for a train of bunches passing through a constant-gradient accelerator section, with application to the calculation and minimization of multi-bunch energy spread. (4) Detailed study of field emission and radio frequency breakdown in disk-loaded structures at S-, C- and X-band frequencies under extremely high-gradient conditions, with special attention to thermal effects, radiation, sparking, emission of gases, surface damage through explosive emission and its possible control through RF-gas processing.
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