Abstract
X-rays are a powerful tool for imaging deep inside thick objects under various environments due to their
high penetrating power. The ultrashort pulse duration of X-ray free-electron lasers (XFELs) adds a new
possibility to achieve higher spatial resolution for radiation sensitive samples by performing X-ray
snapshot imaging free from radiation damage. Coherent diffractive imaging (CDI), which allows X-ray
nano-imaging without objective lenses, is a suitable tool for XFEL imaging. CDI can quantitatively
image transparent phase objects, such as tiny biological samples, by numerically retrieving the phase of
the diffraction data. In imaging dynamics in biology, it is critically important to perform measurement
under controlled hydrated condition at physiological temperatures. The authors are developing a pulsed
coherent X-ray solution scattering (PCXSS), which is an XFEL CDI for solution samples. This article
describes the basics of PCXSS and its application to various samples, including living cells and the selfassemblies
of gold nano-particles in solution, using the Japanese XFEL facility, SACLA.
