Theory and simulations of novel plasma-based accelerators and light sources

We begin by introducing both the Plasma Beat Wave Accelerator (PBWA) and the Plasma Wakefield Accelerator (PWFA). After these two methods of producing relativistic electron plasma waves have been introduced, we begin our study of certain key accelerator issues relevant to plasma-based accelerators. Analytic results for important quantities of interest, such as maximum beam loading current, efficiency, and energy spread that can be obtained from plasma accelerators will be given. These results will be compared with one- and two-dimensional particle-in-cell (PIC) computer simulations.; We then introduce a new method of frequency upshifting short pulses of electromagnetic radiation, which makes use of relativistic plasma waves. This novel method makes use of a fact first noted in chapter 2; namely, that the response of a plasma to a either a short laser pulse or a relativistic electron beam is nearly identical. Thus the laser pulse can be represented by a negatively charged "macroparticle" in the plasma. By analogy, we show that since it is possible to accelerate a charged macroparticle in a plasma wave, acceleration of the laser pulse is also possible. This acceleration is equivalent to upshifting the frequency of the laser.; The effects of quickly creating a plasma around a monochromatic electro-magnetic source wave, on time-scales on the order of a cycle of the wave, is then investigated. It is found that this results in an upshifting of the wave frequency, which can be varied by changing the plasma density. It is also found that a substantial fraction of the B-field associated with the initial wave can be frozen in the plasma as a time independent B-field. For fields generated at the focus of a powerful CO{dollar}sb2{dollar} laser, these fields can be in the megagauss range, making them attractive as wigglers for FELs or other related applications. Computer simulations have been used to study this process in detail, including the effects of finite ionization time. For long ionization times, strong plasma heating results.