Pulse requirements for x-ray diffraction imaging of single biological molecules

In this paper we estimate the required pulse parameters for the future application of x-ray free electron lasers to imaging single biological molecules. The parameters are determined by a tradeoff between minimizing image degradation due to damage and maximizing the image signal-to-noise ratio. We discuss several means to alleviate the pulse requirements, and compare the requirements with parameters of two planned x-ray lasers.