Microfocus Cu K(alpha) source for femtosecond x-ray science.

We demonstrate a subpicosecond 1 kHz femtosecond x-ray source with a well-accessible quasi-point size (10 microm diameter) providing Cu K(alpha) emission with a maximum flux of 6.8 x 10(10) photons/s for continuous operation of 10 h. A new geometry that essentially facilitates the adjustment and diminishes the temporal jitter between the x-ray probe and the laser pump pulse is implemented for time-resolved diffraction experiments.