HUNTSVILLE, Ala., March 31 -- An old photographic technique is helping scientists on the cutting edge of laser research. The Astrophysics Branch in the Space Sciences Laboratory at NASA's Marshall Space Flight Center is providing photographic emulsions for use in detectors inside the petawatt laser facility at Lawrence Livermore National Laboratory in Livermore, Calif.The emulsions record the tracks of nuclear debris from microscopic gold and uranium targets vaporized by the laser. Scientists hope to tailor the design of the petawatt laser so that its advanced descendants might be used to trigger tiny thermonuclear fusion reactions. The petawatt laser also generates conditions that previously were seen only in the most powerful particle accelerators, which conditions might provide some insight into the cause of gamma ray bursts.