After an overview by John Sethian (NRL), sessions were held on lasers (Mercury at LLNL and Electra at NRL), high gain target design (talks from NRL and LLNL), target fabrication and injection (talks from Schafer Corp., GA, and LANL), final optics (talks from UCSD and LLNL), and chambers (talks from U. Wisconsin, LLNL, UCSD, UCSB, INEEL and SNL), and materials (talks from SNL, UCSD, U. Wisconsin, ORNL and UCLA).

In his overview, Sethian stated that the HAPL program is a "coordinated, focussed, multi-lab effort to develop the science and technology for laser fusion energy, based on lasers, direct drive targets and solid wall chambers." He said the program, was one in which a "systems approach" was being used so that "key components would be developed together." He said that "significant progress has recently been made in all key areas." He said the plan was to have the "proof of principle" R&D completed by 2006, assuming the current $25M per year level. Following that, he anticipated the construction of an "integrated research experiment", featuring a reactor scale laser beam line, during 2006-2012. There would follow a power plant laser-fusion test facility, to be operational approximately in 2020. The plan would require budget increases to approximately the $150M per year level during the 2006-2012 period.

Among the many highlights presented at the meeting were the following:

1. The Electra laser at NRL has completed construction of a "first generation" pulsed power system and has operated the system at 5 pulses per second for five hours. The system makes 500 kilovolt electron beams. Theoretical modeling backed with experiments have demonstrated that the electron beam can be patterned to maximize transmission through the foil support structure ("hibachi"). Theoretical modeling has been used to guide the "mitigation of electron beam instability," which also enhances transmission. NRL's partner, Titan Pulse Sciences division, has demonstrated a new solid state laser-triggered pulsed power switch that will become the basis of a pulsedpower system that can meet the requirements for a fusion driver.

2. The Mercury laser at LLNL has developed 160 kilowatt laser diode arrays and demonstrated gas cooling of the laser. About half the system is complete. They have also demonstrated fabrication of large, high quality crystals and have successfully cut slabs from the crystals. They expect to produce 30 joules from the system in CY 2002.

3. UCSD has demonstrated a grazing incidence final optic mirror with high damage threshold. It is based on aluminum coating of a cooled substrate.

4. Schafer Corp. has established the chemistry for low density foam shells. General Atomics has produced spherical shells with thin gold and/or palladium coatings.

5. General Atomics has begun fabrication of a target injection and tracking system.

6. The University of Wisconsin has performed calculations showing "operating windows" for target injection, wall survival and high efficiency.

7. UCSD is developing a code to study chamber clearing between shots.

8. General Atomics has performed calculations indicating that an "nth-of- a-kind" target fabrication factory could produce targets at a cost, delivered to the center of the chamber, of about fifteen cents, an acceptable cost from the viewpoint of power plant economics.

Approximately 70 people attended the workshop.

Vugraphs from this and previous workshops are posted at: http://aries.ucsd.edu/HAPL.