Preservation of high-brightness electron beams during acceleration and compression in linear accelerators is important for free electron lasers. In this talk, I will review the theoretical understanding of a microbunching instability driven by longitudinal space charge in linacs and coherent synchrotron radiation in magnetic bunch compressors. I will show numerical results and experimental evidences how the instability may affect the beam quality for various FEL projects. I will also discuss an effective beam heater designed for the Linac Coherent Light Source to suppress the instability without degrading the FEL performance.
Talk Slides: (Slides when available)