The Matter in Extreme Conditions Upgrade (MEC-U) project is a major upgrade to the MEC instrument on the Linac Coherent Light Source (LCLS) X-ray free electron laser (XFEL) user facility at SLAC National Accelerator Laboratory. The MEC instrument combines the XFEL with a high-power, short-pulse laser and high energy shock driver laser to produce and study high energy density plasmas and materials found in extreme environments such as the interior of stars and fusion reactors, providing the fundamental understanding needed for applications ranging from astronomy to fusion energy. When completed, this project will significantly increase the power and repetition rate of the MEC high intensity laser system to the petawatt level at up to 10 Hz, increase the energy of the shock-driver laser to the kilojoule level, and expand the capabilities of the MEC instrument to support groundbreaking experiments enabled by the combination of high-power lasers with the world's brightest X-ray source. Lawrence Livermore National Laboratory (LLNL) is developing a directly diode-pumped, 10 Hz repetition rate, 150 J, 150 fs, 1 PW laser system to be installed in the upgraded MEC facility. This laser system is an implementation of LLNL's Scalable High power Advanced Radiographic Capability (SHARC) concept and is based on chirped pulse amplification in the diode-pumped, gas-cooled slab architecture developed for the Mercury and HAPLS laser systems. The conceptual design and capabilities of this laser system will be presented.

The design and status of the diode-pumped 10 Hz, 150 J, 150 fs, 1 PW laser system under development for the Matter in Extreme Conditions Upgrade (MEC-U) project will be presented.