“Moving source”: feasibility of diffraction experiment with nanosecond time resolution by the fast synchrotron radiation beam scanning

We propose combination of electronical and X-ray optical scheme that will allow one to fulfil the diffraction experiment with a nanosecond time resolution. In this scheme, a few bunches of electrons will be in the nearest separatrixes. They will move inside the undulator along the different trajectories and at different moments ti. Each trajectory will have a different deviation above the stationary orbit. As a result there will be a shift of the synchrotron radiation (SR) generation point from the equilibrium position. So, a discretely moving source of SR will be created: the SR will be radiated at ti moment and from the ith point. For each ith trajectory of electrons (and for SR), a single-coordinate detector Di will be placed for diffracted radiation collecting from the ith point of the sample. So, every new X-ray diffraction image will be received within time interval ti−1−ti which is equal to a few nanoseconds. The exposure time may be as short as the electron bunch duration and time resolution may be equal to the time interval between bunches. They are 0.1 and 5, 4 ns, respectively, at VEPP-4 storage ring.