  Laser-based sources of ionizing radiation have attracted a considerable
attention in the last years for their broad potential applications. However the
stability and robustness of such sources is still an issue that needs to be
addressed. Aiming to solve such problems, we propose a source that uses a
liquid jet -rather than a solid- as a target for the production of X-rays.
Liquid jets offer always a clean surface for every laser shot which represent a
clear advantage over solids. In this work, we present an experimental
characterization of the X-ray emission of such targets, and study the
efficiency of the process when two temporally delayed pulses are used.
According to the obtained results, the X-ray yield is comparable with commonly
used targets.
