Around the Lab
OMEGA EP Project
March, 2003LLE is launching a multi-year project to build a new ultra-high power laser to complement the ongoing mission of experiments conducted on the OMEGA laser. The new project—OMEGA EP (extended performance)—is a modern architecture 4 beam laser with special capabilities in short-pulse performance (2.6 kJ in a 1-ps pulse).
On February 13, 2003 the United States Congress approved a $13 million allocation for the Laboratory for Laser Energetics to commence construction of the OMEGA EP (Extended Performance) laser system. The OMEGA EP system has been in the preliminary planning stages for the past two years and, when completed, will significantly extend the experimental capabilities at LLE.
Schematic view of the relationship between the existing OMEGA laser system ( left) and the OMEGA EP addition (right). Two of the OMEGA EP beams will be routed through the compression chamber to the existing OMEGA target chamber for certain experiments.
View looking north, along the four beam lines toward the target chamber. A large payload insertion device (LPD) extends from the target chamber.
The OMEGA EP project mission enables LLE to remain a principal support facility for the National Nuclear Security Administration’s (NNSA) high-energy-density (HED) physics program and provides a staging facility for the National Ignition Facility (NIF). Project goals include the development and implementation of higher intensity backlighting schemes and new diagnostic development. Fast-ignition studies will extend the range and configuration flexibility for inertial confinement fusion (ICF) experiments to support NNSA’s current and future needs. Furthermore, a significant portion of experimental time on OMEGA EP will be made available to external users. This will continue LLE’s tradition of mutual cooperation with the national laboratories, extend the options for the NLUF program, and expand LLE’s mission of educating future scientists and researchers. OMEGA EP’s anticipated shot rate of once every two-hours enables the system to meet all of its program goals.
The new system consists of four, NIF-like laser beams, a new target chamber and a vacuum compression chamber to house the large aperture gratings all housed in a new facility. Two beams are based on OPCPA compression technology, producing high-energy, short pulses (2.6 kJ in 1 ps) that can be directed to either the new or existing OMEGA target chambers for fast-ignition ICF experiments or higher-intensity backlighting experiments. Alternatively, all four beams can be frequency tripled to UV light, producing 20 kJ in 1 to 10 ns pulses, then directed to the new target chamber for HED experiments.
Illustration of all four OMEGA EP laser beam paths to the target chamber.
Overview of the OMEGA EP laser system. A beam (pink) is shown entering the compression chamber on the left.
The new OMEGA EP laser system will employ recent advances in ICF laser technology including an optical parametric, chirped-pulse amplification (OPCPA), multipass laser amplifier architecture based on a 40-cm square beam aperture, and large aperture grating technology. OMEGA EP will also provide unique experimental opportunities when used in combination with the OMEGA lasers’ proven cryogenic target implosion capability. The combination of the two systems will result in the world’s only facility capable of fully integrated fast-ignition experiments. In addition, new types of HED physics experiments will be performed on this system.
The flexibility obtained with the new target chamber and the complementary capability to support both direct- and indirect-drive experiments combine to make OMEGA EP an important tool in achieving the ultimate goal for ICF experiments. Construction of the new facility will begin in summer of 2003 and initial operations of OMEGA EP are scheduled for fiscal year 2007.