From SLAC Today: “Seen Around SLAC: HELEN Has a New Home” 

by Lori Ann White

A 30-year-old laser built to simulate the conditions at the heart of a nuclear explosion arrived at SLAC last week, where members of the Linac Coherent Light Source’s Laser Science and Technology Department want to put it to a more peaceful use.

The High Energy Laser Embodying Neodymium, or HELEN, is a neodymium-doped glass laser originally commissioned at Britain’s Atomic Weapons Establishment in 1979 in a ceremony presided over by Queen Elizabeth. But now that AWE [Atomic Weapons Establishment. in Britain] has a new, more powerful laser of its own called Orion, HELEN needed a new home, and LCLS scientists were only too happy to oblige.

‘ I’m very excited about this laser,’ said LCLS laser physicist Greg Hays, whose job it was to bring HELEN safely over from England. It may be 30 years old, he said, but it will still pack a punch in the kilo-joule range once it’s up and running: ‘ It’s essentially the grandfather of the National Ignition Facility at Lawrence Livermore National Laboratory, which is the world’s largest and most energetic laser, with a goal of achieving nuclear fusion and energy gain in the laboratory for the first time.

The laser will probably be focused on the target chamber for the LCLS’s Matter in Extreme Conditions instrument.”