![Image - 3-D rendering of a gold nanocrystal, with are...](/sites/default/files/styles/card/public/images/2013-05-28-Gold-Nanocrystals-3-D-Expansion-Contraction-990_0.jpg?h=fe29df24&itok=l6FkVLqJ)
![Image - A superthin diamond glows blue during a beam-sharing experiment at SLAC's Linac Coherent Light Source X-ray laser. (Credit: Diling Zhu, SLAC)](/sites/default/files/styles/card/public/images/130312-blue-diamond-full_0.jpg?h=7a91d091&itok=rFZOXtbF)
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The X-ray pump-probe (XPP) instrument predominantly uses ultrashort optical laser pulses to generate transient states of matter which are subsequently probed by hard X-ray pulses from the LCLS. The X-ray pulses help to reveal structural dynamics initiated by the laser excitation at the timescale of atomic motions in solid, liquid and gaseous specimens.